Repository: nareix/joy4
Branch: master
Commit: 05a4ffbb5369
Files: 62
Total size: 376.2 KB

Directory structure:
gitextract_naask5op/

├── LICENSE
├── README.md
├── av/
│   ├── av.go
│   ├── avconv/
│   │   └── avconv.go
│   ├── avutil/
│   │   └── avutil.go
│   ├── pktque/
│   │   ├── buf.go
│   │   ├── filters.go
│   │   └── timeline.go
│   ├── pubsub/
│   │   └── queue.go
│   └── transcode/
│       └── transcode.go
├── cgo/
│   └── ffmpeg/
│       ├── audio.go
│       ├── ffmpeg.go
│       ├── ffmpeg.h
│       └── video.go
├── codec/
│   ├── aacparser/
│   │   └── parser.go
│   ├── codec.go
│   ├── fake/
│   │   └── fake.go
│   └── h264parser/
│       ├── parser.go
│       └── parser_test.go
├── doc.go
├── examples/
│   ├── audio_decode/
│   │   └── main.go
│   ├── http_flv_and_rtmp_server/
│   │   └── main.go
│   ├── open_probe_file/
│   │   └── main.go
│   ├── rtmp_publish/
│   │   └── main.go
│   ├── rtmp_server_channels/
│   │   └── main.go
│   ├── rtmp_server_proxy/
│   │   └── main.go
│   ├── rtmp_server_speex_to_aac/
│   │   └── main.go
│   └── transcode/
│       └── main.go
├── format/
│   ├── aac/
│   │   └── aac.go
│   ├── flv/
│   │   ├── flv.go
│   │   └── flvio/
│   │       ├── amf0.go
│   │       └── flvio.go
│   ├── format.go
│   ├── mp4/
│   │   ├── demuxer.go
│   │   ├── handler.go
│   │   ├── mp4io/
│   │   │   ├── atoms.go
│   │   │   ├── gen/
│   │   │   │   ├── gen.go
│   │   │   │   └── pattern.go
│   │   │   └── mp4io.go
│   │   ├── muxer.go
│   │   └── stream.go
│   ├── rtmp/
│   │   └── rtmp.go
│   ├── rtsp/
│   │   ├── client.go
│   │   ├── conn.go
│   │   ├── sdp/
│   │   │   ├── parser.go
│   │   │   └── parser_test.go
│   │   └── stream.go
│   └── ts/
│       ├── demuxer.go
│       ├── handler.go
│       ├── muxer.go
│       ├── stream.go
│       └── tsio/
│           ├── checksum.go
│           └── tsio.go
└── utils/
    └── bits/
        ├── bits.go
        ├── bits_test.go
        ├── bufio/
        │   └── bufio.go
        ├── golomb_reader.go
        └── pio/
            ├── pio.go
            ├── reader.go
            ├── vec.go
            ├── vec_test.go
            └── writer.go

================================================
FILE CONTENTS
================================================

================================================
FILE: LICENSE
================================================
MIT License

Copyright (c) 2017 

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.


================================================
FILE: README.md
================================================
# PLEASE USE joy5 INSTEAD

[joy5](https://github.com/nareix/joy5)

- High performance Copy-on-write gop cache [code](https://github.com/nareix/joy5/blob/master/cmd/avtool/pubsub.go)
- Better av.Packet design [code](https://github.com/nareix/joy5/blob/master/av/av.go)

# JOY4

> Golang audio/video library and streaming server

JOY4 is powerful library written in golang, well-designed interface makes a few lines of code can do a lot of things such as reading, writing, transcoding among variety media formats, or setting up high-performance live streaming server.

# Features 

Well-designed and easy-to-use interfaces:

- Muxer / Demuxer ([doc](https://godoc.org/github.com/nareix/joy4/av#Demuxer) [example](https://github.com/nareix/joy4/blob/master/examples/open_probe_file/main.go))
- Audio Decoder ([doc](https://godoc.org/github.com/nareix/joy4/av#AudioDecoder) [example](https://github.com/nareix/joy4/blob/master/examples/audio_decode/main.go))
- Transcoding ([doc](https://godoc.org/github.com/nareix/joy4/av/transcode) [example](https://github.com/nareix/joy4/blob/master/examples/transcode/main.go))
- Streaming server ([example](https://github.com/nareix/joy4/blob/master/examples/http_flv_and_rtmp_server/main.go))

Support container formats:

- MP4
- MPEG-TS
- FLV
- AAC (ADTS)

RTSP Client
- High level camera bug tolerance
- Support STAP-A

RTMP Client
- Support publishing to nginx-rtmp-server
- Support playing

RTMP / HTTP-FLV Server 
- Support publishing clients: OBS / ffmpeg / Flash Player (>8)
- Support playing clients: Flash Player 11 / VLC / ffplay / mpv
- High performance


Publisher-subscriber packet buffer queue ([doc](https://godoc.org/github.com/nareix/joy4/av/pubsub))

- Customize publisher buffer time and subscriber read position


- Multiple channels live streaming ([example](https://github.com/nareix/joy4/blob/master/examples/rtmp_server_channels/main.go))

Packet filters ([doc](https://godoc.org/github.com/nareix/joy4/av/pktque))

- Wait first keyframe
- Fix timestamp
- Make A/V sync
- Customize ([example](https://github.com/nareix/joy4/blob/master/examples/rtmp_server_channels/main.go#L19))

FFMPEG Golang-style binding ([doc](https://godoc.org/github.com/nareix/joy4/cgo/ffmpeg))
- Audio Encoder / Decoder
- Video Decoder
- Audio Resampler

Support codec and container parsers:

- H264 SPS/PPS/AVCDecoderConfigure parser ([doc](https://godoc.org/github.com/nareix/joy4/codec/h264parser))
- AAC ADTSHeader/MPEG4AudioConfig parser ([doc](https://godoc.org/github.com/nareix/joy4/codec/aacparser))
- MP4 Atoms parser ([doc](https://godoc.org/github.com/nareix/joy4/format/mp4/mp4io))
- FLV AMF0 object parser ([doc](https://godoc.org/github.com/nareix/joy4/format/flv/flvio))

# Requirements

Go version >= 1.6

ffmpeg version >= 3.0 (optional)

# TODO

HLS / MPEG-DASH Server

ffmpeg.VideoEncoder / ffmpeg.SWScale

# License

MIT


================================================
FILE: av/av.go
================================================

// Package av defines basic interfaces and data structures of container demux/mux and audio encode/decode.
package av

import (
	"fmt"
	"time"
)

// Audio sample format.
type SampleFormat uint8

const (
	U8 = SampleFormat(iota + 1) // 8-bit unsigned integer
	S16 // signed 16-bit integer
	S32 // signed 32-bit integer
	FLT // 32-bit float
	DBL // 64-bit float
	U8P // 8-bit unsigned integer in planar
	S16P // signed 16-bit integer in planar
	S32P // signed 32-bit integer in planar
	FLTP // 32-bit float in planar
	DBLP // 64-bit float in planar
	U32 // unsigned 32-bit integer
)

func (self SampleFormat) BytesPerSample() int {
	switch self {
	case U8, U8P:
		return 1
	case S16, S16P:
		return 2
	case FLT, FLTP, S32, S32P, U32:
		return 4
	case DBL, DBLP:
		return 8
	default:
		return 0
	}
}

func (self SampleFormat) String() string {
	switch self {
	case U8:
		return "U8"
	case S16:
		return "S16"
	case S32:
		return "S32"
	case FLT:
		return "FLT"
	case DBL:
		return "DBL"
	case U8P:
		return "U8P"
	case S16P:
		return "S16P"
	case FLTP:
		return "FLTP"
	case DBLP:
		return "DBLP"
	case U32:
		return "U32"
	default:
		return "?"
	}
}

// Check if this sample format is in planar.
func (self SampleFormat) IsPlanar() bool {
	switch self {
	case S16P, S32P, FLTP, DBLP:
		return true
	default:
		return false
	}
}

// Audio channel layout.
type ChannelLayout uint16

func (self ChannelLayout) String() string {
	return fmt.Sprintf("%dch", self.Count())
}

const (
	CH_FRONT_CENTER = ChannelLayout(1 << iota)
	CH_FRONT_LEFT
	CH_FRONT_RIGHT
	CH_BACK_CENTER
	CH_BACK_LEFT
	CH_BACK_RIGHT
	CH_SIDE_LEFT
	CH_SIDE_RIGHT
	CH_LOW_FREQ
	CH_NR

	CH_MONO     = ChannelLayout(CH_FRONT_CENTER)
	CH_STEREO   = ChannelLayout(CH_FRONT_LEFT | CH_FRONT_RIGHT)
	CH_2_1      = ChannelLayout(CH_STEREO | CH_BACK_CENTER)
	CH_2POINT1  = ChannelLayout(CH_STEREO | CH_LOW_FREQ)
	CH_SURROUND = ChannelLayout(CH_STEREO | CH_FRONT_CENTER)
	CH_3POINT1  = ChannelLayout(CH_SURROUND | CH_LOW_FREQ)
	// TODO: add all channel_layout in ffmpeg
)

func (self ChannelLayout) Count() (n int) {
	for self != 0 {
		n++
		self = (self - 1) & self
	}
	return
}

// Video/Audio codec type. can be H264/AAC/SPEEX/...
type CodecType uint32

var (
	H264 = MakeVideoCodecType(avCodecTypeMagic + 1)
	AAC       = MakeAudioCodecType(avCodecTypeMagic + 1)
	PCM_MULAW = MakeAudioCodecType(avCodecTypeMagic + 2)
	PCM_ALAW  = MakeAudioCodecType(avCodecTypeMagic + 3)
	SPEEX = MakeAudioCodecType(avCodecTypeMagic + 4)
	NELLYMOSER = MakeAudioCodecType(avCodecTypeMagic + 5)
)

const codecTypeAudioBit = 0x1
const codecTypeOtherBits = 1

func (self CodecType) String() string {
	switch self {
	case H264:
		return "H264"
	case AAC:
		return "AAC"
	case PCM_MULAW:
		return "PCM_MULAW"
	case PCM_ALAW:
		return "PCM_ALAW"
	case SPEEX:
		return "SPEEX"
	case NELLYMOSER:
		return "NELLYMOSER"
	}
	return ""
}

func (self CodecType) IsAudio() bool {
	return self&codecTypeAudioBit != 0
}

func (self CodecType) IsVideo() bool {
	return self&codecTypeAudioBit == 0
}

// Make a new audio codec type.
func MakeAudioCodecType(base uint32) (c CodecType) {
	c = CodecType(base)<<codecTypeOtherBits | CodecType(codecTypeAudioBit)
	return
}

// Make a new video codec type.
func MakeVideoCodecType(base uint32) (c CodecType) {
	c = CodecType(base) << codecTypeOtherBits
	return
}

const avCodecTypeMagic = 233333

// CodecData is some important bytes for initializing audio/video decoder,
// can be converted to VideoCodecData or AudioCodecData using:
//
//     codecdata.(AudioCodecData) or codecdata.(VideoCodecData)
// 
// for H264, CodecData is AVCDecoderConfigure bytes, includes SPS/PPS.
type CodecData interface {
	Type() CodecType // Video/Audio codec type
}

type VideoCodecData interface {
	CodecData
	Width() int // Video width
	Height() int // Video height
}

type AudioCodecData interface {
	CodecData
	SampleFormat() SampleFormat // audio sample format
	SampleRate() int // audio sample rate
	ChannelLayout() ChannelLayout // audio channel layout
	PacketDuration([]byte) (time.Duration, error) // get audio compressed packet duration
}

type PacketWriter interface {
	WritePacket(Packet) error
}

type PacketReader interface {
	ReadPacket() (Packet,error)
}

// Muxer describes the steps of writing compressed audio/video packets into container formats like MP4/FLV/MPEG-TS.
// 
// Container formats, rtmp.Conn, and transcode.Muxer implements Muxer interface.
type Muxer interface {
	WriteHeader([]CodecData) error // write the file header
	PacketWriter // write compressed audio/video packets
	WriteTrailer() error // finish writing file, this func can be called only once
}

// Muxer with Close() method
type MuxCloser interface {
	Muxer
	Close() error
}

// Demuxer can read compressed audio/video packets from container formats like MP4/FLV/MPEG-TS.
type Demuxer interface {
	PacketReader // read compressed audio/video packets
	Streams() ([]CodecData, error) // reads the file header, contains video/audio meta infomations
}

// Demuxer with Close() method
type DemuxCloser interface {
	Demuxer
	Close() error
}

// Packet stores compressed audio/video data.
type Packet struct {
	IsKeyFrame      bool // video packet is key frame
	Idx             int8 // stream index in container format
	CompositionTime time.Duration // packet presentation time minus decode time for H264 B-Frame
	Time time.Duration // packet decode time
	Data            []byte // packet data
}

// Raw audio frame.
type AudioFrame struct {
	SampleFormat  SampleFormat // audio sample format, e.g: S16,FLTP,...
	ChannelLayout ChannelLayout // audio channel layout, e.g: CH_MONO,CH_STEREO,...
	SampleCount   int // sample count in this frame
	SampleRate    int // sample rate
	Data          [][]byte // data array for planar format len(Data) > 1
}

func (self AudioFrame) Duration() time.Duration {
	return time.Second * time.Duration(self.SampleCount) / time.Duration(self.SampleRate)
}

// Check this audio frame has same format as other audio frame.
func (self AudioFrame) HasSameFormat(other AudioFrame) bool {
	if self.SampleRate != other.SampleRate {
		return false
	}
	if self.ChannelLayout != other.ChannelLayout {
		return false
	}
	if self.SampleFormat != other.SampleFormat {
		return false
	}
	return true
}

// Split sample audio sample from this frame.
func (self AudioFrame) Slice(start int, end int) (out AudioFrame) {
	if start > end {
		panic(fmt.Sprintf("av: AudioFrame split failed start=%d end=%d invalid", start, end))
	}
	out = self
	out.Data = append([][]byte(nil), out.Data...)
	out.SampleCount = end - start
	size := self.SampleFormat.BytesPerSample()
	for i := range out.Data {
		out.Data[i] = out.Data[i][start*size : end*size]
	}
	return
}

// Concat two audio frames.
func (self AudioFrame) Concat(in AudioFrame) (out AudioFrame) {
	out = self
	out.Data = append([][]byte(nil), out.Data...)
	out.SampleCount += in.SampleCount
	for i := range out.Data {
		out.Data[i] = append(out.Data[i], in.Data[i]...)
	}
	return
}

// AudioEncoder can encode raw audio frame into compressed audio packets.
// cgo/ffmpeg inplements AudioEncoder, using ffmpeg.NewAudioEncoder to create it.
type AudioEncoder interface {
	CodecData() (AudioCodecData, error) // encoder's codec data can put into container
	Encode(AudioFrame) ([][]byte, error) // encode raw audio frame into compressed pakcet(s)
	Close() // close encoder, free cgo contexts
	SetSampleRate(int) (error) // set encoder sample rate
	SetChannelLayout(ChannelLayout) (error) // set encoder channel layout
	SetSampleFormat(SampleFormat) (error) // set encoder sample format
	SetBitrate(int) (error) // set encoder bitrate
	SetOption(string,interface{}) (error) // encoder setopt, in ffmpeg is av_opt_set_dict()
	GetOption(string,interface{}) (error) // encoder getopt
}

// AudioDecoder can decode compressed audio packets into raw audio frame.
// use ffmpeg.NewAudioDecoder to create it.
type AudioDecoder interface {
	Decode([]byte) (bool, AudioFrame, error) // decode one compressed audio packet
	Close() // close decode, free cgo contexts
}

// AudioResampler can convert raw audio frames in different sample rate/format/channel layout.
type AudioResampler interface {
	Resample(AudioFrame) (AudioFrame, error) // convert raw audio frames
}



================================================
FILE: av/avconv/avconv.go
================================================
package avconv

import (
	"fmt"
	"io"
	"time"
	"github.com/nareix/joy4/av/avutil"
	"github.com/nareix/joy4/av"
	"github.com/nareix/joy4/av/pktque"
	"github.com/nareix/joy4/av/transcode"
)

var Debug bool

type Option struct {
	Transcode bool
	Args []string
}

type Options struct {
	OutputCodecTypes []av.CodecType
}

type Demuxer struct {
	transdemux *transcode.Demuxer
	streams []av.CodecData
	Options
	Demuxer av.Demuxer
}

func (self *Demuxer) Close() (err error) {
	if self.transdemux != nil {
		return self.transdemux.Close()
	}
	return
}

func (self *Demuxer) Streams() (streams []av.CodecData, err error) {
	if err = self.prepare(); err != nil {
		return
	}
	streams = self.streams
	return
}

func (self *Demuxer) ReadPacket() (pkt av.Packet, err error) {
	if err = self.prepare(); err != nil {
		return
	}
	return self.transdemux.ReadPacket()
}

func (self *Demuxer) prepare() (err error) {
	if self.transdemux != nil {
		return
	}

	/*
	var streams []av.CodecData
	if streams, err = self.Demuxer.Streams(); err != nil {
		return
	}
	*/

	supports := self.Options.OutputCodecTypes

	transopts := transcode.Options{}
	transopts.FindAudioDecoderEncoder = func(codec av.AudioCodecData, i int) (ok bool, dec av.AudioDecoder, enc av.AudioEncoder, err error) {
		if len(supports) == 0 {
			return
		}

		support := false
		for _, typ := range supports {
			if typ == codec.Type() {
				support = true
			}
		}

		if support {
			return
		}
		ok = true

		var enctype av.CodecType
		for _, typ:= range supports {
			if typ.IsAudio() {
				if enc, _ = avutil.DefaultHandlers.NewAudioEncoder(typ); enc != nil {
					enctype = typ
					break
				}
			}
		}
		if enc == nil {
			err = fmt.Errorf("avconv: convert %s->%s failed", codec.Type(), enctype)
			return
		}

		// TODO: support per stream option
		// enc.SetSampleRate ...

		if dec, err = avutil.DefaultHandlers.NewAudioDecoder(codec); err != nil {
			err = fmt.Errorf("avconv: decode %s failed", codec.Type())
			return
		}

		return
	}

	self.transdemux = &transcode.Demuxer{
		Options: transopts,
		Demuxer: self.Demuxer,
	}
	if self.streams, err = self.transdemux.Streams(); err != nil {
		return
	}

	return
}

func ConvertCmdline(args []string) (err error) {
	output := ""
	input := ""
	flagi := false
	flagv := false
	flagt := false
	flagre := false
	duration := time.Duration(0)
	options := Options{}

	for _, arg := range args {
		switch arg {
		case "-i":
			flagi = true

		case "-v":
			flagv = true

		case "-t":
			flagt = true

		case "-re":
			flagre = true

		default:
			switch {
			case flagi:
				flagi = false
				input = arg

			case flagt:
				flagt = false
				var f float64
				fmt.Sscanf(arg, "%f", &f)
				duration = time.Duration(f*float64(time.Second))

			default:
				output = arg
			}
		}
	}

	if input == "" {
		err = fmt.Errorf("avconv: input file not specified")
		return
	}

	if output == "" {
		err = fmt.Errorf("avconv: output file not specified")
		return
	}

	var demuxer av.DemuxCloser
	var muxer av.MuxCloser

	if demuxer, err = avutil.Open(input); err != nil {
		return
	}
	defer demuxer.Close()

	var handler avutil.RegisterHandler
	if handler, muxer, err = avutil.DefaultHandlers.FindCreate(output); err != nil {
		return
	}
	defer muxer.Close()

	options.OutputCodecTypes = handler.CodecTypes

	convdemux := &Demuxer{
		Options: options,
		Demuxer: demuxer,
	}
	defer convdemux.Close()

	var streams []av.CodecData
	if streams, err = demuxer.Streams(); err != nil {
		return
	}

	var convstreams []av.CodecData
	if convstreams, err = convdemux.Streams(); err != nil {
		return
	}

	if flagv {
		for _, stream := range streams {
			fmt.Print(stream.Type(), " ")
		}
		fmt.Print("-> ")
		for _, stream := range convstreams {
			fmt.Print(stream.Type(), " ")
		}
		fmt.Println()
	}

	if err = muxer.WriteHeader(convstreams); err != nil {
		return
	}

	filters := pktque.Filters{}
	if flagre {
		filters = append(filters, &pktque.Walltime{})
	}
	filterdemux := &pktque.FilterDemuxer{
		Demuxer: convdemux,
		Filter: filters,
	}

	for {
		var pkt av.Packet
		if pkt, err = filterdemux.ReadPacket(); err != nil {
			if err == io.EOF {
				err = nil
				break
			}
			return
		}
		if flagv {
			fmt.Println(pkt.Idx, pkt.Time, len(pkt.Data), pkt.IsKeyFrame)
		}
		if duration != 0 && pkt.Time > duration {
			break
		}
		if err = muxer.WritePacket(pkt); err != nil {
			return
		}
	}

	if err = muxer.WriteTrailer(); err != nil {
		return
	}

	return
}



================================================
FILE: av/avutil/avutil.go
================================================
package avutil

import (
	"io"
	"strings"
	"fmt"
	"bytes"
	"github.com/nareix/joy4/av"
	"net/url"
	"os"
	"path"
)

type HandlerDemuxer struct {
	av.Demuxer
	r io.ReadCloser
}

func (self *HandlerDemuxer) Close() error {
	return self.r.Close()
}

type HandlerMuxer struct {
	av.Muxer
	w io.WriteCloser
	stage int
}

func (self *HandlerMuxer) WriteHeader(streams []av.CodecData) (err error) {
	if self.stage == 0 {
		if err = self.Muxer.WriteHeader(streams); err != nil {
			return
		}
		self.stage++
	}
	return
}

func (self *HandlerMuxer) WriteTrailer() (err error) {
	if self.stage == 1 {
		self.stage++
		if err = self.Muxer.WriteTrailer(); err != nil {
			return
		}
	}
	return
}

func (self *HandlerMuxer) Close() (err error) {
	if err = self.WriteTrailer(); err != nil {
		return
	}
	return self.w.Close()
}

type RegisterHandler struct {
	Ext string
	ReaderDemuxer func(io.Reader)av.Demuxer
	WriterMuxer func(io.Writer)av.Muxer
	UrlMuxer func(string)(bool,av.MuxCloser,error)
	UrlDemuxer func(string)(bool,av.DemuxCloser,error)
	UrlReader func(string)(bool,io.ReadCloser,error)
	Probe func([]byte)bool
	AudioEncoder func(av.CodecType)(av.AudioEncoder,error)
	AudioDecoder func(av.AudioCodecData)(av.AudioDecoder,error)
	ServerDemuxer func(string)(bool,av.DemuxCloser,error)
	ServerMuxer func(string)(bool,av.MuxCloser,error)
	CodecTypes []av.CodecType
}

type Handlers struct {
	handlers []RegisterHandler
}

func (self *Handlers) Add(fn func(*RegisterHandler)) {
	handler := &RegisterHandler{}
	fn(handler)
	self.handlers = append(self.handlers, *handler)
}

func (self *Handlers) openUrl(u *url.URL, uri string) (r io.ReadCloser, err error) {
	if u != nil && u.Scheme != "" {
		for _, handler := range self.handlers {
			if handler.UrlReader != nil {
				var ok bool
				if ok, r, err = handler.UrlReader(uri); ok {
					return
				}
			}
		}
		err = fmt.Errorf("avutil: openUrl %s failed", uri)
	} else {
		r, err = os.Open(uri)
	}
	return
}

func (self *Handlers) createUrl(u *url.URL, uri string) (w io.WriteCloser, err error) {
	w, err = os.Create(uri)
	return
}

func (self *Handlers) NewAudioEncoder(typ av.CodecType) (enc av.AudioEncoder, err error) {
	for _, handler := range self.handlers {
		if handler.AudioEncoder != nil {
			if enc, _ = handler.AudioEncoder(typ); enc != nil {
				return
			}
		}
	}
	err = fmt.Errorf("avutil: encoder", typ, "not found")
	return
}

func (self *Handlers) NewAudioDecoder(codec av.AudioCodecData) (dec av.AudioDecoder, err error) {
	for _, handler := range self.handlers {
		if handler.AudioDecoder != nil {
			if dec, _ = handler.AudioDecoder(codec); dec != nil {
				return
			}
		}
	}
	err = fmt.Errorf("avutil: decoder", codec.Type(), "not found")
	return
}

func (self *Handlers) Open(uri string) (demuxer av.DemuxCloser, err error) {
	listen := false
	if strings.HasPrefix(uri, "listen:") {
		uri = uri[len("listen:"):]
		listen = true
	}

	for _, handler := range self.handlers {
		if listen {
			if handler.ServerDemuxer != nil {
				var ok bool
				if ok, demuxer, err = handler.ServerDemuxer(uri); ok {
					return
				}
			}
		} else {
			if handler.UrlDemuxer != nil {
				var ok bool
				if ok, demuxer, err = handler.UrlDemuxer(uri); ok {
					return
				}
			}
		}
	}

	var r io.ReadCloser
	var ext string
	var u *url.URL
	if u, _ = url.Parse(uri); u != nil && u.Scheme != "" {
		ext = path.Ext(u.Path)
	} else {
		ext = path.Ext(uri)
	}

	if ext != "" {
		for _, handler := range self.handlers {
			if handler.Ext == ext {
				if handler.ReaderDemuxer != nil {
					if r, err = self.openUrl(u, uri); err != nil {
						return
					}
					demuxer = &HandlerDemuxer{
						Demuxer: handler.ReaderDemuxer(r),
						r: r,
					}
					return
				}
			}
		}
	}

	var probebuf [1024]byte
	if r, err = self.openUrl(u, uri); err != nil {
		return
	}
	if _, err = io.ReadFull(r, probebuf[:]); err != nil {
		return
	}

	for _, handler := range self.handlers {
		if handler.Probe != nil && handler.Probe(probebuf[:]) && handler.ReaderDemuxer != nil {
			var _r io.Reader
			if rs, ok := r.(io.ReadSeeker); ok {
				if _, err = rs.Seek(0, 0); err != nil {
					return
				}
				_r = rs
			} else {
				_r = io.MultiReader(bytes.NewReader(probebuf[:]), r)
			}
			demuxer = &HandlerDemuxer{
				Demuxer: handler.ReaderDemuxer(_r),
				r: r,
			}
			return
		}
	}

	r.Close()
	err = fmt.Errorf("avutil: open %s failed", uri)
	return
}

func (self *Handlers) Create(uri string) (muxer av.MuxCloser, err error) {
	_, muxer, err = self.FindCreate(uri)
	return
}

func (self *Handlers) FindCreate(uri string) (handler RegisterHandler, muxer av.MuxCloser, err error) {
	listen := false
	if strings.HasPrefix(uri, "listen:") {
		uri = uri[len("listen:"):]
		listen = true
	}

	for _, handler = range self.handlers {
		if listen {
			if handler.ServerMuxer != nil {
				var ok bool
				if ok, muxer, err = handler.ServerMuxer(uri); ok {
					return
				}
			}
		} else {
			if handler.UrlMuxer != nil {
				var ok bool
				if ok, muxer, err = handler.UrlMuxer(uri); ok {
					return
				}
			}
		}
	}

	var ext string
	var u *url.URL
	if u, _ = url.Parse(uri); u != nil && u.Scheme != "" {
		ext = path.Ext(u.Path)
	} else {
		ext = path.Ext(uri)
	}

	if ext != "" {
		for _, handler = range self.handlers {
			if handler.Ext == ext && handler.WriterMuxer != nil {
				var w io.WriteCloser
				if w, err = self.createUrl(u, uri); err != nil {
					return
				}
				muxer = &HandlerMuxer{
					Muxer: handler.WriterMuxer(w),
					w: w,
				}
				return
			}
		}
	}

	err = fmt.Errorf("avutil: create muxer %s failed", uri)
	return
}

var DefaultHandlers = &Handlers{}

func Open(url string) (demuxer av.DemuxCloser, err error) {
	return DefaultHandlers.Open(url)
}

func Create(url string) (muxer av.MuxCloser, err error) {
	return DefaultHandlers.Create(url)
}

func CopyPackets(dst av.PacketWriter, src av.PacketReader) (err error) {
	for {
		var pkt av.Packet
		if pkt, err = src.ReadPacket(); err != nil {
			if err == io.EOF {
				break
			}
			return
		}
		if err = dst.WritePacket(pkt); err != nil {
			return
		}
	}
	return
}

func CopyFile(dst av.Muxer, src av.Demuxer) (err error) {
	var streams []av.CodecData
	if streams, err = src.Streams(); err != nil {
		return
	}
	if err = dst.WriteHeader(streams); err != nil {
		return
	}
	if err = CopyPackets(dst, src); err != nil {
		if err != io.EOF {
			return
		}
	}
	if err = dst.WriteTrailer(); err != nil {
		return
	}
	return
}


================================================
FILE: av/pktque/buf.go
================================================
package pktque

import (
	"github.com/nareix/joy4/av"
)

type Buf struct {
	Head, Tail BufPos
	pkts       []av.Packet
	Size       int
	Count      int
}

func NewBuf() *Buf {
	return &Buf{
		pkts: make([]av.Packet, 64),
	}
}

func (self *Buf) Pop() av.Packet {
	if self.Count == 0 {
		panic("pktque.Buf: Pop() when count == 0")
	}

	i := int(self.Head) & (len(self.pkts) - 1)
	pkt := self.pkts[i]
	self.pkts[i] = av.Packet{}
	self.Size -= len(pkt.Data)
	self.Head++
	self.Count--

	return pkt
}

func (self *Buf) grow() {
	newpkts := make([]av.Packet, len(self.pkts)*2)
	for i := self.Head; i.LT(self.Tail); i++ {
		newpkts[int(i)&(len(newpkts)-1)] = self.pkts[int(i)&(len(self.pkts)-1)]
	}
	self.pkts = newpkts
}

func (self *Buf) Push(pkt av.Packet) {
	if self.Count == len(self.pkts) {
		self.grow()
	}
	self.pkts[int(self.Tail)&(len(self.pkts)-1)] = pkt
	self.Tail++
	self.Count++
	self.Size += len(pkt.Data)
}

func (self *Buf) Get(pos BufPos) av.Packet {
	return self.pkts[int(pos)&(len(self.pkts)-1)]
}

func (self *Buf) IsValidPos(pos BufPos) bool {
	return pos.GE(self.Head) && pos.LT(self.Tail)
}

type BufPos int

func (self BufPos) LT(pos BufPos) bool {
	return self-pos < 0
}

func (self BufPos) GE(pos BufPos) bool {
	return self-pos >= 0
}

func (self BufPos) GT(pos BufPos) bool {
	return self-pos > 0
}


================================================
FILE: av/pktque/filters.go
================================================

// Package pktque provides packet Filter interface and structures used by other components.
package pktque

import (
	"time"
	"github.com/nareix/joy4/av"
)

type Filter interface {
	// Change packet time or drop packet
	ModifyPacket(pkt *av.Packet, streams []av.CodecData, videoidx int, audioidx int) (drop bool, err error)
}

// Combine multiple Filters into one, ModifyPacket will be called in order.
type Filters []Filter

func (self Filters) ModifyPacket(pkt *av.Packet, streams []av.CodecData, videoidx int, audioidx int) (drop bool, err error) {
	for _, filter := range self {
		if drop, err = filter.ModifyPacket(pkt, streams, videoidx, audioidx); err != nil {
			return
		}
		if drop {
			return
		}
	}
	return
}

// Wrap origin Demuxer and Filter into a new Demuxer, when read this Demuxer filters will be called.
type FilterDemuxer struct {
	av.Demuxer
	Filter Filter
	streams []av.CodecData
	videoidx int
	audioidx int
}

func (self FilterDemuxer) ReadPacket() (pkt av.Packet, err error) {
	if self.streams == nil {
		if self.streams, err = self.Demuxer.Streams(); err != nil {
			return
		}
		for i, stream := range self.streams {
			if stream.Type().IsVideo() {
				self.videoidx = i
			} else if stream.Type().IsAudio() {
				self.audioidx = i
			}
		}
	}

	for {
		if pkt, err = self.Demuxer.ReadPacket(); err != nil {
			return
		}
		var drop bool
		if drop, err = self.Filter.ModifyPacket(&pkt, self.streams, self.videoidx, self.audioidx); err != nil {
			return
		}
		if !drop {
			break
		}
	}

	return
}

// Drop packets until first video key frame arrived.
type WaitKeyFrame struct {
	ok bool
}

func (self *WaitKeyFrame) ModifyPacket(pkt *av.Packet, streams []av.CodecData, videoidx int, audioidx int) (drop bool, err error) {
	if !self.ok && pkt.Idx == int8(videoidx) && pkt.IsKeyFrame {
		self.ok = true
	}
	drop = !self.ok
	return
}

// Fix incorrect packet timestamps.
type FixTime struct {
	zerobase time.Duration
	incrbase time.Duration
	lasttime time.Duration
	StartFromZero bool // make timestamp start from zero
	MakeIncrement bool // force timestamp increment
}

func (self *FixTime) ModifyPacket(pkt *av.Packet, streams []av.CodecData, videoidx int, audioidx int) (drop bool, err error) {
	if self.StartFromZero {
		if self.zerobase == 0 {
			self.zerobase = pkt.Time
		}
		pkt.Time -= self.zerobase
	}

	if self.MakeIncrement {
		pkt.Time -= self.incrbase
		if self.lasttime == 0 {
			self.lasttime = pkt.Time
		}
		if pkt.Time < self.lasttime || pkt.Time > self.lasttime+time.Millisecond*500 {
			self.incrbase += pkt.Time - self.lasttime
			pkt.Time = self.lasttime
		}
		self.lasttime = pkt.Time
	}

	return
}

// Drop incorrect packets to make A/V sync.
type AVSync struct {
	MaxTimeDiff time.Duration
	time []time.Duration
}

func (self *AVSync) ModifyPacket(pkt *av.Packet, streams []av.CodecData, videoidx int, audioidx int) (drop bool, err error) {
	if self.time == nil {
		self.time = make([]time.Duration, len(streams))
		if self.MaxTimeDiff == 0 {
			self.MaxTimeDiff = time.Millisecond*500
		}
	}

	start, end, correctable, correcttime := self.check(int(pkt.Idx))
	if pkt.Time >= start && pkt.Time < end {
		self.time[pkt.Idx] = pkt.Time
	} else {
		if correctable {
			pkt.Time = correcttime
			for i := range self.time {
				self.time[i] = correcttime
			}
		} else {
			drop = true
		}
	}
	return
}

func (self *AVSync) check(i int) (start time.Duration, end time.Duration, correctable bool, correcttime time.Duration) {
	minidx := -1
	maxidx := -1
	for j := range self.time {
		if minidx == -1 || self.time[j] < self.time[minidx] {
			minidx = j
		}
		if maxidx == -1 || self.time[j] > self.time[maxidx] {
			maxidx = j
		}
	}
	allthesame := self.time[minidx] == self.time[maxidx]

	if i == maxidx {
		if allthesame {
			correctable = true
		} else {
			correctable = false
		}
	} else {
		correctable = true
	}

	start = self.time[minidx]
	end = start + self.MaxTimeDiff
	correcttime = start + time.Millisecond*40
	return
}

// Make packets reading speed as same as walltime, effect like ffmpeg -re option.
type Walltime struct {
	firsttime time.Time
}

func (self *Walltime) ModifyPacket(pkt *av.Packet, streams []av.CodecData, videoidx int, audioidx int) (drop bool, err error) {
	if pkt.Idx == 0 {
		if self.firsttime.IsZero() {
			self.firsttime = time.Now()
		}
		pkttime := self.firsttime.Add(pkt.Time)
		delta := pkttime.Sub(time.Now())
		if delta > 0 {
			time.Sleep(delta)
		}
	}
	return
}



================================================
FILE: av/pktque/timeline.go
================================================
package pktque

import (
	"time"
)

/*
pop                                   push

     seg                 seg        seg
  |--------|         |---------|   |---|
     20ms                40ms       5ms
----------------- time -------------------->
headtm                               tailtm
*/

type tlSeg struct {
	tm, dur time.Duration
}

type Timeline struct {
	segs []tlSeg
	headtm time.Duration
}

func (self *Timeline) Push(tm time.Duration, dur time.Duration) {
	if len(self.segs) > 0 {
		tail := self.segs[len(self.segs)-1]
		diff := tm-(tail.tm+tail.dur)
		if diff < 0 {
			tm -= diff
		}
	}
	self.segs = append(self.segs, tlSeg{tm, dur})
}

func (self *Timeline) Pop(dur time.Duration) (tm time.Duration) {
	if len(self.segs) == 0 {
		return self.headtm
	}

	tm = self.segs[0].tm
	for dur > 0 && len(self.segs) > 0 {
		seg := &self.segs[0]
		sub := dur
		if seg.dur < sub {
			sub = seg.dur
		}
		seg.dur -= sub
		dur -= sub
		seg.tm += sub
		self.headtm += sub
		if seg.dur == 0 {
			copy(self.segs[0:], self.segs[1:])
			self.segs = self.segs[:len(self.segs)-1]
		}
	}

	return
}



================================================
FILE: av/pubsub/queue.go
================================================
// Packege pubsub implements publisher-subscribers model used in multi-channel streaming.
package pubsub

import (
	"github.com/nareix/joy4/av"
	"github.com/nareix/joy4/av/pktque"
	"io"
	"sync"
	"time"
)

//        time
// ----------------->
//
// V-A-V-V-A-V-V-A-V-V
// |                 |
// 0        5        10
// head             tail
// oldest          latest
//

// One publisher and multiple subscribers thread-safe packet buffer queue.
type Queue struct {
	buf                      *pktque.Buf
	head, tail               int
	lock                     *sync.RWMutex
	cond                     *sync.Cond
	curgopcount, maxgopcount int
	streams                  []av.CodecData
	videoidx                 int
	closed                   bool
}

func NewQueue() *Queue {
	q := &Queue{}
	q.buf = pktque.NewBuf()
	q.maxgopcount = 2
	q.lock = &sync.RWMutex{}
	q.cond = sync.NewCond(q.lock.RLocker())
	q.videoidx = -1
	return q
}

func (self *Queue) SetMaxGopCount(n int) {
	self.lock.Lock()
	self.maxgopcount = n
	self.lock.Unlock()
	return
}

func (self *Queue) WriteHeader(streams []av.CodecData) error {
	self.lock.Lock()

	self.streams = streams
	for i, stream := range streams {
		if stream.Type().IsVideo() {
			self.videoidx = i
		}
	}
	self.cond.Broadcast()

	self.lock.Unlock()

	return nil
}

func (self *Queue) WriteTrailer() error {
	return nil
}

// After Close() called, all QueueCursor's ReadPacket will return io.EOF.
func (self *Queue) Close() (err error) {
	self.lock.Lock()

	self.closed = true
	self.cond.Broadcast()

	self.lock.Unlock()
	return
}

// Put packet into buffer, old packets will be discared.
func (self *Queue) WritePacket(pkt av.Packet) (err error) {
	self.lock.Lock()

	self.buf.Push(pkt)
	if pkt.Idx == int8(self.videoidx) && pkt.IsKeyFrame {
		self.curgopcount++
	}

	for self.curgopcount >= self.maxgopcount && self.buf.Count > 1 {
		pkt := self.buf.Pop()
		if pkt.Idx == int8(self.videoidx) && pkt.IsKeyFrame {
			self.curgopcount--
		}
		if self.curgopcount < self.maxgopcount {
			break
		}
	}
	//println("shrink", self.curgopcount, self.maxgopcount, self.buf.Head, self.buf.Tail, "count", self.buf.Count, "size", self.buf.Size)

	self.cond.Broadcast()

	self.lock.Unlock()
	return
}

type QueueCursor struct {
	que    *Queue
	pos    pktque.BufPos
	gotpos bool
	init   func(buf *pktque.Buf, videoidx int) pktque.BufPos
}

func (self *Queue) newCursor() *QueueCursor {
	return &QueueCursor{
		que: self,
	}
}

// Create cursor position at latest packet.
func (self *Queue) Latest() *QueueCursor {
	cursor := self.newCursor()
	cursor.init = func(buf *pktque.Buf, videoidx int) pktque.BufPos {
		return buf.Tail
	}
	return cursor
}

// Create cursor position at oldest buffered packet.
func (self *Queue) Oldest() *QueueCursor {
	cursor := self.newCursor()
	cursor.init = func(buf *pktque.Buf, videoidx int) pktque.BufPos {
		return buf.Head
	}
	return cursor
}

// Create cursor position at specific time in buffered packets.
func (self *Queue) DelayedTime(dur time.Duration) *QueueCursor {
	cursor := self.newCursor()
	cursor.init = func(buf *pktque.Buf, videoidx int) pktque.BufPos {
		i := buf.Tail - 1
		if buf.IsValidPos(i) {
			end := buf.Get(i)
			for buf.IsValidPos(i) {
				if end.Time-buf.Get(i).Time > dur {
					break
				}
				i--
			}
		}
		return i
	}
	return cursor
}

// Create cursor position at specific delayed GOP count in buffered packets.
func (self *Queue) DelayedGopCount(n int) *QueueCursor {
	cursor := self.newCursor()
	cursor.init = func(buf *pktque.Buf, videoidx int) pktque.BufPos {
		i := buf.Tail - 1
		if videoidx != -1 {
			for gop := 0; buf.IsValidPos(i) && gop < n; i-- {
				pkt := buf.Get(i)
				if pkt.Idx == int8(self.videoidx) && pkt.IsKeyFrame {
					gop++
				}
			}
		}
		return i
	}
	return cursor
}

func (self *QueueCursor) Streams() (streams []av.CodecData, err error) {
	self.que.cond.L.Lock()
	for self.que.streams == nil && !self.que.closed {
		self.que.cond.Wait()
	}
	if self.que.streams != nil {
		streams = self.que.streams
	} else {
		err = io.EOF
	}
	self.que.cond.L.Unlock()
	return
}

// ReadPacket will not consume packets in Queue, it's just a cursor.
func (self *QueueCursor) ReadPacket() (pkt av.Packet, err error) {
	self.que.cond.L.Lock()
	buf := self.que.buf
	if !self.gotpos {
		self.pos = self.init(buf, self.que.videoidx)
		self.gotpos = true
	}
	for {
		if self.pos.LT(buf.Head) {
			self.pos = buf.Head
		} else if self.pos.GT(buf.Tail) {
			self.pos = buf.Tail
		}
		if buf.IsValidPos(self.pos) {
			pkt = buf.Get(self.pos)
			self.pos++
			break
		}
		if self.que.closed {
			err = io.EOF
			break
		}
		self.que.cond.Wait()
	}
	self.que.cond.L.Unlock()
	return
}


================================================
FILE: av/transcode/transcode.go
================================================

// Package transcoder implements Transcoder based on Muxer/Demuxer and AudioEncoder/AudioDecoder interface.
package transcode

import (
	"fmt"
	"time"
	"github.com/nareix/joy4/av"
	"github.com/nareix/joy4/av/pktque"
)

var Debug bool

type tStream struct {
	codec av.CodecData
	timeline *pktque.Timeline
	aencodec, adecodec av.AudioCodecData
	aenc av.AudioEncoder
	adec av.AudioDecoder
}

type Options struct {
	// check if transcode is needed, and create the AudioDecoder and AudioEncoder.
	FindAudioDecoderEncoder func(codec av.AudioCodecData, i int) (
		need bool, dec av.AudioDecoder, enc av.AudioEncoder, err error,
	)
}

type Transcoder struct {
	streams                 []*tStream
}

func NewTranscoder(streams []av.CodecData, options Options) (_self *Transcoder, err error) {
	self := &Transcoder{}
	self.streams = []*tStream{}

	for i, stream := range streams {
		ts := &tStream{codec: stream}
		if stream.Type().IsAudio() {
			if options.FindAudioDecoderEncoder != nil {
				var ok bool
				var enc av.AudioEncoder
				var dec av.AudioDecoder
				ok, dec, enc, err = options.FindAudioDecoderEncoder(stream.(av.AudioCodecData), i)
				if ok {
					if err != nil {
						return
					}
					ts.timeline = &pktque.Timeline{}
					if ts.codec, err = enc.CodecData(); err != nil {
						return
					}
					ts.aencodec = ts.codec.(av.AudioCodecData)
					ts.adecodec = stream.(av.AudioCodecData)
					ts.aenc = enc
					ts.adec = dec
				}
			}
		}
		self.streams = append(self.streams, ts)
	}

	_self = self
	return
}

func (self *tStream) audioDecodeAndEncode(inpkt av.Packet) (outpkts []av.Packet, err error) {
	var dur time.Duration
	var frame av.AudioFrame
	var ok bool
	if ok, frame, err = self.adec.Decode(inpkt.Data); err != nil {
		return
	}
	if !ok {
		return
	}

	if dur, err = self.adecodec.PacketDuration(inpkt.Data); err != nil {
		err = fmt.Errorf("transcode: PacketDuration() failed for input stream #%d", inpkt.Idx)
		return
	}

	if Debug {
		fmt.Println("transcode: push", inpkt.Time, dur)
	}
	self.timeline.Push(inpkt.Time, dur)

	var _outpkts [][]byte
	if _outpkts, err = self.aenc.Encode(frame); err != nil {
		return
	}
	for _, _outpkt := range _outpkts {
		if dur, err = self.aencodec.PacketDuration(_outpkt); err != nil {
			err = fmt.Errorf("transcode: PacketDuration() failed for output stream #%d", inpkt.Idx)
			return
		}
		outpkt := av.Packet{Idx: inpkt.Idx, Data: _outpkt}
		outpkt.Time = self.timeline.Pop(dur)

		if Debug {
			fmt.Println("transcode: pop", outpkt.Time, dur)
		}

		outpkts = append(outpkts, outpkt)
	}

	return
}

// Do the transcode.
// 
// In audio transcoding one Packet may transcode into many Packets
// packet time will be adjusted automatically.
func (self *Transcoder) Do(pkt av.Packet) (out []av.Packet, err error) {
	stream := self.streams[pkt.Idx]
	if stream.aenc != nil && stream.adec != nil {
		if out, err = stream.audioDecodeAndEncode(pkt); err != nil {
			return
		}
	} else {
		out = append(out, pkt)
	}
	return
}

// Get CodecDatas after transcoding.
func (self *Transcoder) Streams() (streams []av.CodecData, err error) {
	for _, stream := range self.streams {
		streams = append(streams, stream.codec)
	}
	return
}

// Close transcoder, close related encoder and decoders.
func (self *Transcoder) Close() (err error) {
	for _, stream := range self.streams {
		if stream.aenc != nil {
			stream.aenc.Close()
			stream.aenc = nil
		}
		if stream.adec != nil {
			stream.adec.Close()
			stream.adec = nil
		}
	}
	self.streams = nil
	return
}

// Wrap transcoder and origin Muxer into new Muxer.
// Write to new Muxer will do transcoding automatically.
type Muxer struct {
	av.Muxer // origin Muxer
	Options // transcode options
	transcoder *Transcoder
}

func (self *Muxer) WriteHeader(streams []av.CodecData) (err error) {
	if self.transcoder, err = NewTranscoder(streams, self.Options); err != nil {
		return
	}
	var newstreams []av.CodecData
	if newstreams, err = self.transcoder.Streams(); err != nil {
		return
	}
	if err = self.Muxer.WriteHeader(newstreams); err != nil {
		return
	}
	return
}

func (self *Muxer) WritePacket(pkt av.Packet) (err error) {
	var outpkts []av.Packet
	if outpkts, err = self.transcoder.Do(pkt); err != nil {
		return
	}
	for _, pkt := range outpkts {
		if err = self.Muxer.WritePacket(pkt); err != nil {
			return
		}
	}
	return
}

func (self *Muxer) Close() (err error) {
	if self.transcoder != nil {
		return self.transcoder.Close()
	}
	return
}

// Wrap transcoder and origin Demuxer into new Demuxer.
// Read this Demuxer will do transcoding automatically.
type Demuxer struct {
	av.Demuxer
	Options
	transcoder *Transcoder
	outpkts []av.Packet
}

func (self *Demuxer) prepare() (err error) {
	if self.transcoder == nil {
		var streams []av.CodecData
		if streams, err = self.Demuxer.Streams(); err != nil {
			return
		}
		if self.transcoder, err = NewTranscoder(streams, self.Options); err != nil {
			return
		}
	}
	return
}

func (self *Demuxer) ReadPacket() (pkt av.Packet, err error) {
	if err = self.prepare(); err != nil {
		return
	}
	for {
		if len(self.outpkts) > 0 {
			pkt = self.outpkts[0]
			self.outpkts = self.outpkts[1:]
			return
		}
		var rpkt av.Packet
		if rpkt, err = self.Demuxer.ReadPacket(); err != nil {
			return
		}
		if self.outpkts, err = self.transcoder.Do(rpkt); err != nil {
			return
		}
	}
	return
}

func (self *Demuxer) Streams() (streams []av.CodecData, err error) {
	if err = self.prepare(); err != nil {
		return
	}
	return self.transcoder.Streams()
}

func (self *Demuxer) Close() (err error) {
	if self.transcoder != nil {
		return self.transcoder.Close()
	}
	return
}


================================================
FILE: cgo/ffmpeg/audio.go
================================================
package ffmpeg

/*
#include "ffmpeg.h"
int wrap_avcodec_decode_audio4(AVCodecContext *ctx, AVFrame *frame, void *data, int size, int *got) {
	struct AVPacket pkt = {.data = data, .size = size};
	return avcodec_decode_audio4(ctx, frame, got, &pkt);
}
int wrap_avresample_convert(AVAudioResampleContext *avr, int *out, int outsize, int outcount, int *in, int insize, int incount) {
	return avresample_convert(avr, (void *)out, outsize, outcount, (void *)in, insize, incount);
}
*/
import "C"
import (
	"unsafe"
	"runtime"
	"fmt"
	"time"
	"github.com/nareix/joy4/av"
	"github.com/nareix/joy4/av/avutil"
	"github.com/nareix/joy4/codec/aacparser"
)

const debug = false

type Resampler struct {
	inSampleFormat, OutSampleFormat av.SampleFormat
	inChannelLayout, OutChannelLayout av.ChannelLayout
	inSampleRate, OutSampleRate int
	avr *C.AVAudioResampleContext
}

func (self *Resampler) Resample(in av.AudioFrame) (out av.AudioFrame, err error) {
	formatChange := in.SampleRate != self.inSampleRate || in.SampleFormat != self.inSampleFormat || in.ChannelLayout != self.inChannelLayout

	var flush av.AudioFrame

	if formatChange {
		if self.avr != nil {
			outChannels := self.OutChannelLayout.Count()
			if !self.OutSampleFormat.IsPlanar() {
				outChannels = 1
			}
			outData := make([]*C.uint8_t, outChannels)
			outSampleCount := int(C.avresample_get_out_samples(self.avr, C.int(in.SampleCount)))
			outLinesize := outSampleCount*self.OutSampleFormat.BytesPerSample()
			flush.Data = make([][]byte, outChannels)
			for i := 0; i < outChannels; i++ {
				flush.Data[i] = make([]byte, outLinesize)
				outData[i] = (*C.uint8_t)(unsafe.Pointer(&flush.Data[i][0]))
			}
			flush.ChannelLayout = self.OutChannelLayout
			flush.SampleFormat = self.OutSampleFormat
			flush.SampleRate = self.OutSampleRate

			convertSamples := int(C.wrap_avresample_convert(
				self.avr,
				(*C.int)(unsafe.Pointer(&outData[0])), C.int(outLinesize), C.int(outSampleCount),
				nil, C.int(0), C.int(0),
			))
			if convertSamples < 0 {
				err = fmt.Errorf("ffmpeg: avresample_convert_frame failed")
				return
			}
			flush.SampleCount = convertSamples
			if convertSamples < outSampleCount {
				for i := 0; i < outChannels; i++ {
					flush.Data[i] = flush.Data[i][:convertSamples*self.OutSampleFormat.BytesPerSample()]
				}
			}

			//fmt.Println("flush:", "outSampleCount", outSampleCount, "convertSamples", convertSamples, "datasize", len(flush.Data[0]))
		} else {
			runtime.SetFinalizer(self, func(self *Resampler) {
				self.Close()
			})
		}

		C.avresample_free(&self.avr)
		self.inSampleFormat = in.SampleFormat
		self.inSampleRate = in.SampleRate
		self.inChannelLayout = in.ChannelLayout
		avr := C.avresample_alloc_context()
		C.av_opt_set_int(unsafe.Pointer(avr), C.CString("in_channel_layout"), C.int64_t(channelLayoutAV2FF(self.inChannelLayout)), 0)
		C.av_opt_set_int(unsafe.Pointer(avr), C.CString("out_channel_layout"), C.int64_t(channelLayoutAV2FF(self.OutChannelLayout)), 0)
		C.av_opt_set_int(unsafe.Pointer(avr), C.CString("in_sample_rate"), C.int64_t(self.inSampleRate), 0)
		C.av_opt_set_int(unsafe.Pointer(avr), C.CString("out_sample_rate"), C.int64_t(self.OutSampleRate), 0)
		C.av_opt_set_int(unsafe.Pointer(avr), C.CString("in_sample_fmt"), C.int64_t(sampleFormatAV2FF(self.inSampleFormat)), 0)
		C.av_opt_set_int(unsafe.Pointer(avr), C.CString("out_sample_fmt"), C.int64_t(sampleFormatAV2FF(self.OutSampleFormat)), 0)
		C.avresample_open(avr)
		self.avr = avr
	}

	var inChannels, inLinesize int
	inSampleCount := in.SampleCount
	if !self.inSampleFormat.IsPlanar() {
		inChannels = 1
		inLinesize = inSampleCount*in.SampleFormat.BytesPerSample()*self.inChannelLayout.Count()
	} else {
		inChannels = self.inChannelLayout.Count()
		inLinesize = inSampleCount*in.SampleFormat.BytesPerSample()
	}
	inData := make([]*C.uint8_t, inChannels)
	for i := 0; i < inChannels; i++ {
		inData[i] = (*C.uint8_t)(unsafe.Pointer(&in.Data[i][0]))
	}

	var outChannels, outLinesize, outBytesPerSample int
	outSampleCount := int(C.avresample_get_out_samples(self.avr, C.int(in.SampleCount)))
	if !self.OutSampleFormat.IsPlanar() {
		outChannels = 1
		outBytesPerSample = self.OutSampleFormat.BytesPerSample()*self.OutChannelLayout.Count()
		outLinesize = outSampleCount*outBytesPerSample
	} else {
		outChannels = self.OutChannelLayout.Count()
		outBytesPerSample = self.OutSampleFormat.BytesPerSample()
		outLinesize = outSampleCount*outBytesPerSample
	}
	outData := make([]*C.uint8_t, outChannels)
	out.Data = make([][]byte, outChannels)
	for i := 0; i < outChannels; i++ {
		out.Data[i] = make([]byte, outLinesize)
		outData[i] = (*C.uint8_t)(unsafe.Pointer(&out.Data[i][0]))
	}
	out.ChannelLayout = self.OutChannelLayout
	out.SampleFormat = self.OutSampleFormat
	out.SampleRate = self.OutSampleRate

	convertSamples := int(C.wrap_avresample_convert(
		self.avr,
		(*C.int)(unsafe.Pointer(&outData[0])), C.int(outLinesize), C.int(outSampleCount),
		(*C.int)(unsafe.Pointer(&inData[0])), C.int(inLinesize), C.int(inSampleCount),
	))
	if convertSamples < 0 {
		err = fmt.Errorf("ffmpeg: avresample_convert_frame failed")
		return
	}

	out.SampleCount = convertSamples
	if convertSamples < outSampleCount {
		for i := 0; i < outChannels; i++ {
			out.Data[i] = out.Data[i][:convertSamples*outBytesPerSample]
		}
	}

	if flush.SampleCount > 0 {
		out = flush.Concat(out)
	}

	return
}

func (self *Resampler) Close() {
	C.avresample_free(&self.avr)
}

type AudioEncoder struct {
	ff *ffctx
	SampleRate int
	Bitrate int
	ChannelLayout av.ChannelLayout
	SampleFormat av.SampleFormat
	FrameSampleCount int
	framebuf av.AudioFrame
	codecData av.AudioCodecData
	resampler *Resampler
}

func sampleFormatAV2FF(sampleFormat av.SampleFormat) (ffsamplefmt int32) {
	switch sampleFormat {
	case av.U8:
		ffsamplefmt = C.AV_SAMPLE_FMT_U8
	case av.S16:
		ffsamplefmt = C.AV_SAMPLE_FMT_S16
	case av.S32:
		ffsamplefmt = C.AV_SAMPLE_FMT_S32
	case av.FLT:
		ffsamplefmt = C.AV_SAMPLE_FMT_FLT
	case av.DBL:
		ffsamplefmt = C.AV_SAMPLE_FMT_DBL
	case av.U8P:
		ffsamplefmt = C.AV_SAMPLE_FMT_U8P
	case av.S16P:
		ffsamplefmt = C.AV_SAMPLE_FMT_S16P
	case av.S32P:
		ffsamplefmt = C.AV_SAMPLE_FMT_S32P
	case av.FLTP:
		ffsamplefmt = C.AV_SAMPLE_FMT_FLTP
	case av.DBLP:
		ffsamplefmt = C.AV_SAMPLE_FMT_DBLP
	}
	return
}

func sampleFormatFF2AV(ffsamplefmt int32) (sampleFormat av.SampleFormat) {
	switch ffsamplefmt {
	case C.AV_SAMPLE_FMT_U8:          ///< unsigned 8 bits
		sampleFormat = av.U8
	case C.AV_SAMPLE_FMT_S16:         ///< signed 16 bits
		sampleFormat = av.S16
	case C.AV_SAMPLE_FMT_S32:         ///< signed 32 bits
		sampleFormat = av.S32
	case C.AV_SAMPLE_FMT_FLT:         ///< float
		sampleFormat = av.FLT
	case C.AV_SAMPLE_FMT_DBL:         ///< double
		sampleFormat = av.DBL
	case C.AV_SAMPLE_FMT_U8P:         ///< unsigned 8 bits, planar
		sampleFormat = av.U8P
	case C.AV_SAMPLE_FMT_S16P:        ///< signed 16 bits, planar
		sampleFormat = av.S16P
	case C.AV_SAMPLE_FMT_S32P:        ///< signed 32 bits, planar
		sampleFormat = av.S32P
	case C.AV_SAMPLE_FMT_FLTP:        ///< float, planar
		sampleFormat = av.FLTP
	case C.AV_SAMPLE_FMT_DBLP:        ///< double, planar
		sampleFormat = av.DBLP
	}
	return
}

func (self *AudioEncoder) SetSampleFormat(fmt av.SampleFormat) (err error) {
	self.SampleFormat = fmt
	return
}

func (self *AudioEncoder) SetSampleRate(rate int) (err error) {
	self.SampleRate = rate
	return
}

func (self *AudioEncoder) SetChannelLayout(ch av.ChannelLayout) (err error) {
	self.ChannelLayout = ch
	return
}

func (self *AudioEncoder) SetBitrate(bitrate int) (err error) {
	self.Bitrate = bitrate
	return
}

func (self *AudioEncoder) SetOption(key string, val interface{}) (err error) {
	ff := &self.ff.ff

	sval := fmt.Sprint(val)
	if key == "profile" {
		ff.profile = C.avcodec_profile_name_to_int(ff.codec, C.CString(sval))
		if ff.profile == C.FF_PROFILE_UNKNOWN {
			err = fmt.Errorf("ffmpeg: profile `%s` invalid", sval)
			return
		}
		return
	}

	C.av_dict_set(&ff.options, C.CString(key), C.CString(sval), 0)
	return
}

func (self *AudioEncoder) GetOption(key string, val interface{}) (err error) {
	ff := &self.ff.ff
	entry := C.av_dict_get(ff.options, C.CString(key), nil, 0)
	if entry == nil {
		err = fmt.Errorf("ffmpeg: GetOption failed: `%s` not exists", key)
		return
	}
	switch p := val.(type) {
	case *string:
		*p = C.GoString(entry.value)
	case *int:
		fmt.Sscanf(C.GoString(entry.value), "%d", p)
	default:
		err = fmt.Errorf("ffmpeg: GetOption failed: val must be *string or *int receiver")
		return
	}
	return
}

func (self *AudioEncoder) Setup() (err error) {
	ff := &self.ff.ff

	ff.frame = C.av_frame_alloc()

	if self.SampleFormat == av.SampleFormat(0) {
		self.SampleFormat = sampleFormatFF2AV(*ff.codec.sample_fmts)
	}

	//if self.Bitrate == 0 {
	//	self.Bitrate = 80000
	//}
	if self.SampleRate == 0 {
		self.SampleRate = 44100
	}
	if self.ChannelLayout == av.ChannelLayout(0) {
		self.ChannelLayout = av.CH_STEREO
	}

	ff.codecCtx.sample_fmt = sampleFormatAV2FF(self.SampleFormat)
	ff.codecCtx.sample_rate = C.int(self.SampleRate)
	ff.codecCtx.bit_rate = C.int64_t(self.Bitrate)
	ff.codecCtx.channel_layout = channelLayoutAV2FF(self.ChannelLayout)
	ff.codecCtx.strict_std_compliance = C.FF_COMPLIANCE_EXPERIMENTAL
	ff.codecCtx.flags = C.AV_CODEC_FLAG_GLOBAL_HEADER
	ff.codecCtx.profile = ff.profile

	if C.avcodec_open2(ff.codecCtx, ff.codec, nil) != 0 {
		err = fmt.Errorf("ffmpeg: encoder: avcodec_open2 failed")
		return
	}
	self.SampleFormat = sampleFormatFF2AV(ff.codecCtx.sample_fmt)
	self.FrameSampleCount = int(ff.codecCtx.frame_size)

	extradata := C.GoBytes(unsafe.Pointer(ff.codecCtx.extradata), ff.codecCtx.extradata_size)

	switch ff.codecCtx.codec_id {
	case C.AV_CODEC_ID_AAC:
		if self.codecData, err = aacparser.NewCodecDataFromMPEG4AudioConfigBytes(extradata); err != nil {
			return
		}

	default:
		self.codecData = audioCodecData{
			channelLayout: self.ChannelLayout,
			sampleFormat: self.SampleFormat,
			sampleRate: self.SampleRate,
			codecId: ff.codecCtx.codec_id,
			extradata: extradata,
		}
	}

	return
}

func (self *AudioEncoder) prepare() (err error) {
	ff := &self.ff.ff

	if ff.frame == nil {
		if err = self.Setup(); err != nil {
			return
		}
	}

	return
}

func (self *AudioEncoder) CodecData() (codec av.AudioCodecData, err error) {
	if err = self.prepare(); err != nil {
		return
	}
	codec = self.codecData
	return
}

func (self *AudioEncoder) encodeOne(frame av.AudioFrame) (gotpkt bool, pkt []byte, err error) {
	if err = self.prepare(); err != nil {
		return
	}

	ff := &self.ff.ff

	cpkt := C.AVPacket{}
	cgotpkt := C.int(0)
	audioFrameAssignToFF(frame, ff.frame)

	if false {
		farr := []string{}
		for i := 0; i < len(frame.Data[0])/4; i++ {
			var f *float64 = (*float64)(unsafe.Pointer(&frame.Data[0][i*4]))
			farr = append(farr, fmt.Sprintf("%.8f", *f))
		}
		fmt.Println(farr)
	}
	cerr := C.avcodec_encode_audio2(ff.codecCtx, &cpkt, ff.frame, &cgotpkt)
	if cerr < C.int(0) {
		err = fmt.Errorf("ffmpeg: avcodec_encode_audio2 failed: %d", cerr)
		return
	}

	if cgotpkt != 0 {
		gotpkt = true
		pkt = C.GoBytes(unsafe.Pointer(cpkt.data), cpkt.size)
		C.av_packet_unref(&cpkt)

		if debug {
			fmt.Println("ffmpeg: Encode", frame.SampleCount, frame.SampleRate, frame.ChannelLayout, frame.SampleFormat, "len", len(pkt))
		}
	}

	return
}

func (self *AudioEncoder) resample(in av.AudioFrame) (out av.AudioFrame, err error) {
	if self.resampler == nil {
		self.resampler = &Resampler{
			OutSampleFormat: self.SampleFormat,
			OutSampleRate: self.SampleRate,
			OutChannelLayout: self.ChannelLayout,
		}
	}
	if out, err = self.resampler.Resample(in); err != nil {
		return
	}
	return
}

func (self *AudioEncoder) Encode(frame av.AudioFrame) (pkts [][]byte, err error) {
	var gotpkt bool
	var pkt []byte

	if frame.SampleFormat != self.SampleFormat || frame.ChannelLayout != self.ChannelLayout || frame.SampleRate != self.SampleRate {
		if frame, err = self.resample(frame); err != nil {
			return
		}
	}

	if self.FrameSampleCount != 0 {
		if self.framebuf.SampleCount == 0 {
			self.framebuf = frame
		} else {
			self.framebuf = self.framebuf.Concat(frame)
		}
		for self.framebuf.SampleCount >= self.FrameSampleCount {
			frame := self.framebuf.Slice(0, self.FrameSampleCount)
			if gotpkt, pkt, err = self.encodeOne(frame); err != nil {
				return
			}
			if gotpkt {
				pkts = append(pkts, pkt)
			}
			self.framebuf = self.framebuf.Slice(self.FrameSampleCount, self.framebuf.SampleCount)
		}
	} else {
		if gotpkt, pkt, err = self.encodeOne(frame); err != nil {
			return
		}
		if gotpkt {
			pkts = append(pkts, pkt)
		}
	}

	return
}

func (self *AudioEncoder) Close() {
	freeFFCtx(self.ff)
	if self.resampler != nil {
		self.resampler.Close()
		self.resampler = nil
	}
}

func audioFrameAssignToAVParams(f *C.AVFrame, frame *av.AudioFrame) {
	frame.SampleFormat = sampleFormatFF2AV(int32(f.format))
	frame.ChannelLayout = channelLayoutFF2AV(f.channel_layout)
	frame.SampleRate = int(f.sample_rate)
}

func audioFrameAssignToAVData(f *C.AVFrame, frame *av.AudioFrame) {
	frame.SampleCount = int(f.nb_samples)
	frame.Data = make([][]byte, int(f.channels))
	for i := 0; i < int(f.channels); i++ {
		frame.Data[i] = C.GoBytes(unsafe.Pointer(f.data[i]), f.linesize[0])
	}
}

func audioFrameAssignToAV(f *C.AVFrame, frame *av.AudioFrame) {
	audioFrameAssignToAVParams(f, frame)
	audioFrameAssignToAVData(f, frame)
}

func audioFrameAssignToFFParams(frame av.AudioFrame, f *C.AVFrame) {
	f.format = C.int(sampleFormatAV2FF(frame.SampleFormat))
	f.channel_layout = channelLayoutAV2FF(frame.ChannelLayout)
	f.sample_rate = C.int(frame.SampleRate)
	f.channels = C.int(frame.ChannelLayout.Count())
}

func audioFrameAssignToFFData(frame av.AudioFrame, f *C.AVFrame) {
	f.nb_samples = C.int(frame.SampleCount)
	for i := range frame.Data {
		f.data[i] = (*C.uint8_t)(unsafe.Pointer(&frame.Data[i][0]))
		f.linesize[i] = C.int(len(frame.Data[i]))
	}
}

func audioFrameAssignToFF(frame av.AudioFrame, f *C.AVFrame) {
	audioFrameAssignToFFParams(frame, f)
	audioFrameAssignToFFData(frame, f)
}

func channelLayoutFF2AV(layout C.uint64_t) (channelLayout av.ChannelLayout) {
	if layout & C.AV_CH_FRONT_CENTER != 0 {
		channelLayout |= av.CH_FRONT_CENTER
	}
	if layout & C.AV_CH_FRONT_LEFT != 0 {
		channelLayout |= av.CH_FRONT_LEFT
	}
	if layout & C.AV_CH_FRONT_RIGHT != 0 {
		channelLayout |= av.CH_FRONT_RIGHT
	}
	if layout & C.AV_CH_BACK_CENTER != 0 {
		channelLayout |= av.CH_BACK_CENTER
	}
	if layout & C.AV_CH_BACK_LEFT != 0 {
		channelLayout |= av.CH_BACK_LEFT
	}
	if layout & C.AV_CH_BACK_RIGHT != 0 {
		channelLayout |= av.CH_BACK_RIGHT
	}
	if layout & C.AV_CH_SIDE_LEFT != 0 {
		channelLayout |= av.CH_SIDE_LEFT
	}
	if layout & C.AV_CH_SIDE_RIGHT != 0 {
		channelLayout |= av.CH_SIDE_RIGHT
	}
	if layout & C.AV_CH_LOW_FREQUENCY != 0 {
		channelLayout |= av.CH_LOW_FREQ
	}
	return
}

func channelLayoutAV2FF(channelLayout av.ChannelLayout) (layout C.uint64_t) {
	if channelLayout & av.CH_FRONT_CENTER != 0 {
		layout |= C.AV_CH_FRONT_CENTER
	}
	if channelLayout & av.CH_FRONT_LEFT != 0 {
		layout |= C.AV_CH_FRONT_LEFT
	}
	if channelLayout & av.CH_FRONT_RIGHT != 0 {
		layout |= C.AV_CH_FRONT_RIGHT
	}
	if channelLayout & av.CH_BACK_CENTER != 0 {
		layout |= C.AV_CH_BACK_CENTER
	}
	if channelLayout & av.CH_BACK_LEFT != 0 {
		layout |= C.AV_CH_BACK_LEFT
	}
	if channelLayout & av.CH_BACK_RIGHT != 0 {
		layout |= C.AV_CH_BACK_RIGHT
	}
	if channelLayout & av.CH_SIDE_LEFT != 0 {
		layout |= C.AV_CH_SIDE_LEFT
	}
	if channelLayout & av.CH_SIDE_RIGHT != 0 {
		layout |= C.AV_CH_SIDE_RIGHT
	}
	if channelLayout & av.CH_LOW_FREQ != 0 {
		layout |= C.AV_CH_LOW_FREQUENCY
	}
	return
}

type AudioDecoder struct {
	ff *ffctx
	ChannelLayout av.ChannelLayout
	SampleFormat av.SampleFormat
	SampleRate int
	Extradata []byte
}

func (self *AudioDecoder) Setup() (err error) {
	ff := &self.ff.ff

	ff.frame = C.av_frame_alloc()

	if len(self.Extradata) > 0 {
		ff.codecCtx.extradata = (*C.uint8_t)(unsafe.Pointer(&self.Extradata[0]))
		ff.codecCtx.extradata_size = C.int(len(self.Extradata))
	}
	if debug {
		fmt.Println("ffmpeg: Decoder.Setup Extradata.len", len(self.Extradata))
	}

	ff.codecCtx.sample_rate = C.int(self.SampleRate)
	ff.codecCtx.channel_layout = channelLayoutAV2FF(self.ChannelLayout)
	ff.codecCtx.channels = C.int(self.ChannelLayout.Count())
	if C.avcodec_open2(ff.codecCtx, ff.codec, nil) != 0 {
		err = fmt.Errorf("ffmpeg: decoder: avcodec_open2 failed")
		return
	}
	self.SampleFormat = sampleFormatFF2AV(ff.codecCtx.sample_fmt)
	self.ChannelLayout = channelLayoutFF2AV(ff.codecCtx.channel_layout)
	if self.SampleRate == 0 {
		self.SampleRate = int(ff.codecCtx.sample_rate)
	}

	return
}

func (self *AudioDecoder) Decode(pkt []byte) (gotframe bool, frame av.AudioFrame, err error) {
	ff := &self.ff.ff

	cgotframe := C.int(0)
	cerr := C.wrap_avcodec_decode_audio4(ff.codecCtx, ff.frame, unsafe.Pointer(&pkt[0]), C.int(len(pkt)), &cgotframe)
	if cerr < C.int(0) {
		err = fmt.Errorf("ffmpeg: avcodec_decode_audio4 failed: %d", cerr)
		return
	}

	if cgotframe != C.int(0) {
		gotframe = true
		audioFrameAssignToAV(ff.frame, &frame)
		frame.SampleRate = self.SampleRate

		if debug {
			fmt.Println("ffmpeg: Decode", frame.SampleCount, frame.SampleRate, frame.ChannelLayout, frame.SampleFormat)
		}
	}

	return
}

func (self *AudioDecoder) Close() {
	freeFFCtx(self.ff)
}

func NewAudioEncoderByCodecType(typ av.CodecType) (enc *AudioEncoder, err error) {
	var id uint32

	switch typ {
	case av.AAC:
		id = C.AV_CODEC_ID_AAC

	default:
		err = fmt.Errorf("ffmpeg: cannot find encoder codecType=%d", typ)
		return
	}

	codec := C.avcodec_find_encoder(id)
	if codec == nil || C.avcodec_get_type(id) != C.AVMEDIA_TYPE_AUDIO {
		err = fmt.Errorf("ffmpeg: cannot find audio encoder codecId=%d", id)
		return
	}

	_enc := &AudioEncoder{}
	if _enc.ff, err = newFFCtxByCodec(codec); err != nil {
		return
	}
	enc = _enc
	return
}

func NewAudioEncoderByName(name string) (enc *AudioEncoder, err error) {
	_enc := &AudioEncoder{}

	codec := C.avcodec_find_encoder_by_name(C.CString(name))
	if codec == nil || C.avcodec_get_type(codec.id) != C.AVMEDIA_TYPE_AUDIO {
		err = fmt.Errorf("ffmpeg: cannot find audio encoder name=%s", name)
		return
	}

	if _enc.ff, err = newFFCtxByCodec(codec); err != nil {
		return
	}
	enc = _enc
	return
}

func NewAudioDecoder(codec av.AudioCodecData) (dec *AudioDecoder, err error) {
	_dec := &AudioDecoder{}
	var id uint32

	switch codec.Type() {
	case av.AAC:
		if aaccodec, ok := codec.(aacparser.CodecData); ok {
			_dec.Extradata = aaccodec.MPEG4AudioConfigBytes()
			id = C.AV_CODEC_ID_AAC
		} else {
			err = fmt.Errorf("ffmpeg: aac CodecData must be aacparser.CodecData")
			return
		}

	case av.SPEEX:
		id = C.AV_CODEC_ID_SPEEX

	case av.PCM_MULAW:
		id = C.AV_CODEC_ID_PCM_MULAW

	case av.PCM_ALAW:
		id = C.AV_CODEC_ID_PCM_ALAW

	default:
		if ffcodec, ok := codec.(audioCodecData); ok {
			_dec.Extradata = ffcodec.extradata
			id = ffcodec.codecId
		} else {
			err = fmt.Errorf("ffmpeg: invalid CodecData for ffmpeg to decode")
			return
		}
	}

	c := C.avcodec_find_decoder(id)
	if c == nil || C.avcodec_get_type(c.id) != C.AVMEDIA_TYPE_AUDIO {
		err = fmt.Errorf("ffmpeg: cannot find audio decoder id=%d", id)
		return
	}

	if _dec.ff, err = newFFCtxByCodec(c); err != nil {
		return
	}

	_dec.SampleFormat = codec.SampleFormat()
	_dec.SampleRate = codec.SampleRate()
	_dec.ChannelLayout = codec.ChannelLayout()
	if err = _dec.Setup(); err != nil {
		return
	}

	dec = _dec
	return
}

type audioCodecData struct {
	codecId uint32
	sampleFormat av.SampleFormat
	channelLayout av.ChannelLayout
	sampleRate int
	extradata []byte
}

func (self audioCodecData) Type() av.CodecType {
	return av.MakeAudioCodecType(self.codecId)
}

func (self audioCodecData) SampleRate() int {
	return self.sampleRate
}

func (self audioCodecData) SampleFormat() av.SampleFormat {
	return self.sampleFormat
}

func (self audioCodecData) ChannelLayout() av.ChannelLayout {
	return self.channelLayout
}

func (self audioCodecData) PacketDuration(data []byte) (dur time.Duration, err error) {
	// TODO: implement it: ffmpeg get_audio_frame_duration
	err = fmt.Errorf("ffmpeg: cannot get packet duration")
	return
}

func AudioCodecHandler(h *avutil.RegisterHandler) {
	h.AudioDecoder = func(codec av.AudioCodecData) (av.AudioDecoder, error) {
		if dec, err := NewAudioDecoder(codec); err != nil {
			return nil, nil
		} else {
			return dec, err
		}
	}

	h.AudioEncoder = func(typ av.CodecType) (av.AudioEncoder, error) {
		if enc, err := NewAudioEncoderByCodecType(typ); err != nil {
			return nil, nil
		} else {
			return enc, err
		}
	}
}



================================================
FILE: cgo/ffmpeg/ffmpeg.go
================================================
package ffmpeg

/*
#cgo LDFLAGS: -lavformat -lavutil -lavcodec -lavresample -lswscale
#include "ffmpeg.h"
void ffinit() {
	av_register_all();
}
*/
import "C"
import (
	"runtime"
	"unsafe"
)

const (
	QUIET = int(C.AV_LOG_QUIET)
	PANIC = int(C.AV_LOG_PANIC)
	FATAL = int(C.AV_LOG_FATAL)
	ERROR = int(C.AV_LOG_ERROR)
	WARNING = int(C.AV_LOG_WARNING)
	INFO = int(C.AV_LOG_INFO)
	VERBOSE = int(C.AV_LOG_VERBOSE)
	DEBUG = int(C.AV_LOG_DEBUG)
	TRACE = int(C.AV_LOG_TRACE)
)

func HasEncoder(name string) bool {
	return C.avcodec_find_encoder_by_name(C.CString(name)) != nil
}

func HasDecoder(name string) bool {
	return C.avcodec_find_decoder_by_name(C.CString(name)) != nil
}

//func EncodersList() []string
//func DecodersList() []string

func SetLogLevel(level int) {
	C.av_log_set_level(C.int(level))
}

func init() {
	C.ffinit()
}

type ffctx struct {
	ff C.FFCtx
}

func newFFCtxByCodec(codec *C.AVCodec) (ff *ffctx, err error) {
	ff = &ffctx{}
	ff.ff.codec = codec
	ff.ff.codecCtx = C.avcodec_alloc_context3(codec)
	ff.ff.profile = C.FF_PROFILE_UNKNOWN
	runtime.SetFinalizer(ff, freeFFCtx)
	return
}

func freeFFCtx(self *ffctx) {
	ff := &self.ff
	if ff.frame != nil {
		C.av_frame_free(&ff.frame)
	}
	if ff.codecCtx != nil {
		C.avcodec_close(ff.codecCtx)
		C.av_free(unsafe.Pointer(ff.codecCtx))
		ff.codecCtx = nil
	}
	if ff.options != nil {
		C.av_dict_free(&ff.options)
	}
}



================================================
FILE: cgo/ffmpeg/ffmpeg.h
================================================

#include <libavformat/avformat.h>
#include <libavcodec/avcodec.h>
#include <libavutil/avutil.h>
#include <libavresample/avresample.h>
#include <libavutil/opt.h>
#include <string.h>
#include <libswscale/swscale.h>

typedef struct {
	AVCodec *codec;
	AVCodecContext *codecCtx;
	AVFrame *frame;
	AVDictionary *options;
	int profile;
} FFCtx;

static inline int avcodec_profile_name_to_int(AVCodec *codec, const char *name) {
	const AVProfile *p;
	for (p = codec->profiles; p != NULL && p->profile != FF_PROFILE_UNKNOWN; p++)
		if (!strcasecmp(p->name, name))
			return p->profile;
	return FF_PROFILE_UNKNOWN;
}



================================================
FILE: cgo/ffmpeg/video.go
================================================
package ffmpeg

/*
#include "ffmpeg.h"
int wrap_avcodec_decode_video2(AVCodecContext *ctx, AVFrame *frame, void *data, int size, int *got) {
	struct AVPacket pkt = {.data = data, .size = size};
	return avcodec_decode_video2(ctx, frame, got, &pkt);
}
*/
import "C"
import (
	"unsafe"
	"runtime"
	"fmt"
	"image"
	"reflect"
	"github.com/nareix/joy4/av"
	"github.com/nareix/joy4/codec/h264parser"
)

type VideoDecoder struct {
	ff *ffctx
	Extradata []byte
}

func (self *VideoDecoder) Setup() (err error) {
	ff := &self.ff.ff
	if len(self.Extradata) > 0 {
		ff.codecCtx.extradata = (*C.uint8_t)(unsafe.Pointer(&self.Extradata[0]))
		ff.codecCtx.extradata_size = C.int(len(self.Extradata))
	}
	if C.avcodec_open2(ff.codecCtx, ff.codec, nil) != 0 {
		err = fmt.Errorf("ffmpeg: decoder: avcodec_open2 failed")
		return
	}
	return
}

func fromCPtr(buf unsafe.Pointer, size int) (ret []uint8) {
	hdr := (*reflect.SliceHeader)((unsafe.Pointer(&ret)))
	hdr.Cap = size
	hdr.Len = size
	hdr.Data = uintptr(buf)
	return
}

type VideoFrame struct {
	Image image.YCbCr
	frame *C.AVFrame
}

func (self *VideoFrame) Free() {
	self.Image = image.YCbCr{}
	C.av_frame_free(&self.frame)
}

func freeVideoFrame(self *VideoFrame) {
	self.Free()
}

func (self *VideoDecoder) Decode(pkt []byte) (img *VideoFrame, err error) {
	ff := &self.ff.ff

	cgotimg := C.int(0)
	frame := C.av_frame_alloc()
	cerr := C.wrap_avcodec_decode_video2(ff.codecCtx, frame, unsafe.Pointer(&pkt[0]), C.int(len(pkt)), &cgotimg)
	if cerr < C.int(0) {
		err = fmt.Errorf("ffmpeg: avcodec_decode_video2 failed: %d", cerr)
		return
	}

	if cgotimg != C.int(0) {
		w := int(frame.width)
		h := int(frame.height)
		ys := int(frame.linesize[0])
		cs := int(frame.linesize[1])

		img = &VideoFrame{Image: image.YCbCr{
			Y: fromCPtr(unsafe.Pointer(frame.data[0]), ys*h),
			Cb: fromCPtr(unsafe.Pointer(frame.data[1]), cs*h/2),
			Cr: fromCPtr(unsafe.Pointer(frame.data[2]), cs*h/2),
			YStride: ys,
			CStride: cs,
			SubsampleRatio: image.YCbCrSubsampleRatio420,
			Rect: image.Rect(0, 0, w, h),
		}, frame: frame}
		runtime.SetFinalizer(img, freeVideoFrame)
	}

	return
}

func NewVideoDecoder(stream av.CodecData) (dec *VideoDecoder, err error) {
	_dec := &VideoDecoder{}
	var id uint32

	switch stream.Type() {
	case av.H264:
		h264 := stream.(h264parser.CodecData)
		_dec.Extradata = h264.AVCDecoderConfRecordBytes()
		id = C.AV_CODEC_ID_H264

	default:
		err = fmt.Errorf("ffmpeg: NewVideoDecoder codec=%v unsupported", stream.Type())
		return
	}

	c := C.avcodec_find_decoder(id)
	if c == nil || C.avcodec_get_type(id) != C.AVMEDIA_TYPE_VIDEO {
		err = fmt.Errorf("ffmpeg: cannot find video decoder codecId=%d", id)
		return
	}

	if _dec.ff, err = newFFCtxByCodec(c); err != nil {
		return
	}
	if err =  _dec.Setup(); err != nil {
		return
	}

	dec = _dec
	return
}



================================================
FILE: codec/aacparser/parser.go
================================================
package aacparser

import (
	"github.com/nareix/joy4/utils/bits"
	"github.com/nareix/joy4/av"
	"time"
	"fmt"
	"bytes"
	"io"
)

// copied from libavcodec/mpeg4audio.h
const (
	AOT_AAC_MAIN        = 1 + iota  ///< Y                       Main
	AOT_AAC_LC                      ///< Y                       Low Complexity
	AOT_AAC_SSR                     ///< N (code in SoC repo)    Scalable Sample Rate
	AOT_AAC_LTP                     ///< Y                       Long Term Prediction
	AOT_SBR                         ///< Y                       Spectral Band Replication
	AOT_AAC_SCALABLE                ///< N                       Scalable
	AOT_TWINVQ                      ///< N                       Twin Vector Quantizer
	AOT_CELP                        ///< N                       Code Excited Linear Prediction
	AOT_HVXC                        ///< N                       Harmonic Vector eXcitation Coding
	AOT_TTSI            = 12 + iota ///< N                       Text-To-Speech Interface
	AOT_MAINSYNTH                   ///< N                       Main Synthesis
	AOT_WAVESYNTH                   ///< N                       Wavetable Synthesis
	AOT_MIDI                        ///< N                       General MIDI
	AOT_SAFX                        ///< N                       Algorithmic Synthesis and Audio Effects
	AOT_ER_AAC_LC                   ///< N                       Error Resilient Low Complexity
	AOT_ER_AAC_LTP      = 19 + iota ///< N                       Error Resilient Long Term Prediction
	AOT_ER_AAC_SCALABLE             ///< N                       Error Resilient Scalable
	AOT_ER_TWINVQ                   ///< N                       Error Resilient Twin Vector Quantizer
	AOT_ER_BSAC                     ///< N                       Error Resilient Bit-Sliced Arithmetic Coding
	AOT_ER_AAC_LD                   ///< N                       Error Resilient Low Delay
	AOT_ER_CELP                     ///< N                       Error Resilient Code Excited Linear Prediction
	AOT_ER_HVXC                     ///< N                       Error Resilient Harmonic Vector eXcitation Coding
	AOT_ER_HILN                     ///< N                       Error Resilient Harmonic and Individual Lines plus Noise
	AOT_ER_PARAM                    ///< N                       Error Resilient Parametric
	AOT_SSC                         ///< N                       SinuSoidal Coding
	AOT_PS                          ///< N                       Parametric Stereo
	AOT_SURROUND                    ///< N                       MPEG Surround
	AOT_ESCAPE                      ///< Y                       Escape Value
	AOT_L1                          ///< Y                       Layer 1
	AOT_L2                          ///< Y                       Layer 2
	AOT_L3                          ///< Y                       Layer 3
	AOT_DST                         ///< N                       Direct Stream Transfer
	AOT_ALS                         ///< Y                       Audio LosslesS
	AOT_SLS                         ///< N                       Scalable LosslesS
	AOT_SLS_NON_CORE                ///< N                       Scalable LosslesS (non core)
	AOT_ER_AAC_ELD                  ///< N                       Error Resilient Enhanced Low Delay
	AOT_SMR_SIMPLE                  ///< N                       Symbolic Music Representation Simple
	AOT_SMR_MAIN                    ///< N                       Symbolic Music Representation Main
	AOT_USAC_NOSBR                  ///< N                       Unified Speech and Audio Coding (no SBR)
	AOT_SAOC                        ///< N                       Spatial Audio Object Coding
	AOT_LD_SURROUND                 ///< N                       Low Delay MPEG Surround
	AOT_USAC                        ///< N                       Unified Speech and Audio Coding
)

type MPEG4AudioConfig struct {
	SampleRate      int
	ChannelLayout   av.ChannelLayout
	ObjectType      uint
	SampleRateIndex uint
	ChannelConfig   uint
}

var sampleRateTable = []int{
	96000, 88200, 64000, 48000, 44100, 32000,
	24000, 22050, 16000, 12000, 11025, 8000, 7350,
}

/*
These are the channel configurations:
0: Defined in AOT Specifc Config
1: 1 channel: front-center
2: 2 channels: front-left, front-right
3: 3 channels: front-center, front-left, front-right
4: 4 channels: front-center, front-left, front-right, back-center
5: 5 channels: front-center, front-left, front-right, back-left, back-right
6: 6 channels: front-center, front-left, front-right, back-left, back-right, LFE-channel
7: 8 channels: front-center, front-left, front-right, side-left, side-right, back-left, back-right, LFE-channel
8-15: Reserved
*/
var chanConfigTable = []av.ChannelLayout{
	0,
	av.CH_FRONT_CENTER,
	av.CH_FRONT_LEFT|av.CH_FRONT_RIGHT,
	av.CH_FRONT_CENTER|av.CH_FRONT_LEFT|av.CH_FRONT_RIGHT,
	av.CH_FRONT_CENTER|av.CH_FRONT_LEFT|av.CH_FRONT_RIGHT|av.CH_BACK_CENTER,
	av.CH_FRONT_CENTER|av.CH_FRONT_LEFT|av.CH_FRONT_RIGHT|av.CH_BACK_LEFT|av.CH_BACK_RIGHT,
	av.CH_FRONT_CENTER|av.CH_FRONT_LEFT|av.CH_FRONT_RIGHT|av.CH_BACK_LEFT|av.CH_BACK_RIGHT|av.CH_LOW_FREQ,
	av.CH_FRONT_CENTER|av.CH_FRONT_LEFT|av.CH_FRONT_RIGHT|av.CH_SIDE_LEFT|av.CH_SIDE_RIGHT|av.CH_BACK_LEFT|av.CH_BACK_RIGHT|av.CH_LOW_FREQ,
}

func ParseADTSHeader(frame []byte) (config MPEG4AudioConfig, hdrlen int, framelen int, samples int, err error) {
	if frame[0] != 0xff || frame[1]&0xf6 != 0xf0 {
		err = fmt.Errorf("aacparser: not adts header")
		return
	}
	config.ObjectType = uint(frame[2]>>6) + 1
	config.SampleRateIndex = uint(frame[2] >> 2 & 0xf)
	config.ChannelConfig = uint(frame[2]<<2&0x4 | frame[3]>>6&0x3)
	if config.ChannelConfig == uint(0) {
		err = fmt.Errorf("aacparser: adts channel count invalid")
		return
	}
	(&config).Complete()
	framelen = int(frame[3]&0x3)<<11 | int(frame[4])<<3 | int(frame[5]>>5)
	samples = (int(frame[6]&0x3) + 1) * 1024
	hdrlen = 7
	if frame[1]&0x1 == 0 {
		hdrlen = 9
	}
	if framelen < hdrlen {
		err = fmt.Errorf("aacparser: adts framelen < hdrlen")
		return
	}
	return
}

const ADTSHeaderLength = 7

func FillADTSHeader(header []byte, config MPEG4AudioConfig, samples int, payloadLength int) {
	payloadLength += 7
	//AAAAAAAA AAAABCCD EEFFFFGH HHIJKLMM MMMMMMMM MMMOOOOO OOOOOOPP (QQQQQQQQ QQQQQQQQ)
	header[0] = 0xff
	header[1] = 0xf1
	header[2] = 0x50
	header[3] = 0x80
	header[4] = 0x43
	header[5] = 0xff
	header[6] = 0xcd
	//config.ObjectType = uint(frames[2]>>6)+1
	//config.SampleRateIndex = uint(frames[2]>>2&0xf)
	//config.ChannelConfig = uint(frames[2]<<2&0x4|frames[3]>>6&0x3)
	header[2] = (byte(config.ObjectType-1)&0x3)<<6 | (byte(config.SampleRateIndex)&0xf)<<2 | byte(config.ChannelConfig>>2)&0x1
	header[3] = header[3]&0x3f | byte(config.ChannelConfig&0x3)<<6
	header[3] = header[3]&0xfc | byte(payloadLength>>11)&0x3
	header[4] = byte(payloadLength >> 3)
	header[5] = header[5]&0x1f | (byte(payloadLength)&0x7)<<5
	header[6] = header[6]&0xfc | byte(samples/1024-1)
	return
}

func readObjectType(r *bits.Reader) (objectType uint, err error) {
	if objectType, err = r.ReadBits(5); err != nil {
		return
	}
	if objectType == AOT_ESCAPE {
		var i uint
		if i, err = r.ReadBits(6); err != nil {
			return
		}
		objectType = 32 + i
	}
	return
}

func writeObjectType(w *bits.Writer, objectType uint) (err error) {
	if objectType >= 32 {
		if err = w.WriteBits(AOT_ESCAPE, 5); err != nil {
			return
		}
		if err = w.WriteBits(objectType-32, 6); err != nil {
			return
		}
	} else {
		if err = w.WriteBits(objectType, 5); err != nil {
			return
		}
	}
	return
}

func readSampleRateIndex(r *bits.Reader) (index uint, err error) {
	if index, err = r.ReadBits(4); err != nil {
		return
	}
	if index == 0xf {
		if index, err = r.ReadBits(24); err != nil {
			return
		}
	}
	return
}

func writeSampleRateIndex(w *bits.Writer, index uint) (err error) {
	if index >= 0xf {
		if err = w.WriteBits(0xf, 4); err != nil {
			return
		}
		if err = w.WriteBits(index, 24); err != nil {
			return
		}
	} else {
		if err = w.WriteBits(index, 4); err != nil {
			return
		}
	}
	return
}

func (self MPEG4AudioConfig) IsValid() bool {
	return self.ObjectType > 0
}

func (self *MPEG4AudioConfig) Complete() {
	if int(self.SampleRateIndex) < len(sampleRateTable) {
		self.SampleRate = sampleRateTable[self.SampleRateIndex]
	}
	if int(self.ChannelConfig) < len(chanConfigTable) {
		self.ChannelLayout = chanConfigTable[self.ChannelConfig]
	}
	return
}

func ParseMPEG4AudioConfigBytes(data []byte) (config MPEG4AudioConfig, err error) {
	// copied from libavcodec/mpeg4audio.c avpriv_mpeg4audio_get_config()
	r := bytes.NewReader(data)
	br := &bits.Reader{R: r}
	if config.ObjectType, err = readObjectType(br); err != nil {
		return
	}
	if config.SampleRateIndex, err = readSampleRateIndex(br); err != nil {
		return
	}
	if config.ChannelConfig, err = br.ReadBits(4); err != nil {
		return
	}
	(&config).Complete()
	return
}

func WriteMPEG4AudioConfig(w io.Writer, config MPEG4AudioConfig) (err error) {
	bw := &bits.Writer{W: w}
	if err = writeObjectType(bw, config.ObjectType); err != nil {
		return
	}

	if config.SampleRateIndex == 0 {
		for i, rate := range sampleRateTable {
			if rate == config.SampleRate {
				config.SampleRateIndex = uint(i)
			}
		}
	}
	if err = writeSampleRateIndex(bw, config.SampleRateIndex); err != nil {
		return
	}

	if config.ChannelConfig == 0 {
		for i, layout := range chanConfigTable {
			if layout == config.ChannelLayout {
				config.ChannelConfig = uint(i)
			}
		}
	}
	if err = bw.WriteBits(config.ChannelConfig, 4); err != nil {
		return
	}

	if err = bw.FlushBits(); err != nil {
		return
	}
	return
}

type CodecData struct {
	ConfigBytes []byte
	Config MPEG4AudioConfig
}

func (self CodecData) Type() av.CodecType {
	return av.AAC
}

func (self CodecData) MPEG4AudioConfigBytes() []byte {
	return self.ConfigBytes
}

func (self CodecData) ChannelLayout() av.ChannelLayout {
	return self.Config.ChannelLayout
}

func (self CodecData) SampleRate() int {
	return self.Config.SampleRate
}

func (self CodecData) SampleFormat() av.SampleFormat {
	return av.FLTP
}

func (self CodecData) PacketDuration(data []byte) (dur time.Duration, err error) {
	dur = time.Duration(1024) * time.Second / time.Duration(self.Config.SampleRate)
	return
}

func NewCodecDataFromMPEG4AudioConfig(config MPEG4AudioConfig) (self CodecData, err error) {
	b := &bytes.Buffer{}
	WriteMPEG4AudioConfig(b, config)
	return NewCodecDataFromMPEG4AudioConfigBytes(b.Bytes())
}

func NewCodecDataFromMPEG4AudioConfigBytes(config []byte) (self CodecData, err error) {
	self.ConfigBytes = config
	if self.Config, err = ParseMPEG4AudioConfigBytes(config); err != nil {
		err = fmt.Errorf("aacparser: parse MPEG4AudioConfig failed(%s)", err)
		return
	}
	return
}



================================================
FILE: codec/codec.go
================================================
package codec

import (
	"github.com/nareix/joy4/av"
	"github.com/nareix/joy4/codec/fake"
	"time"
)

type PCMUCodecData struct {
	typ av.CodecType
}

func (self PCMUCodecData) Type() av.CodecType {
	return self.typ
}

func (self PCMUCodecData) SampleRate() int {
	return 8000
}

func (self PCMUCodecData) ChannelLayout() av.ChannelLayout {
	return av.CH_MONO
}

func (self PCMUCodecData) SampleFormat() av.SampleFormat {
	return av.S16
}

func (self PCMUCodecData) PacketDuration(data []byte) (time.Duration, error) {
	return time.Duration(len(data)) * time.Second / time.Duration(8000), nil
}

func NewPCMMulawCodecData() av.AudioCodecData {
	return PCMUCodecData{
		typ: av.PCM_MULAW,
	}
}

func NewPCMAlawCodecData() av.AudioCodecData {
	return PCMUCodecData{
		typ: av.PCM_ALAW,
	}
}

type SpeexCodecData struct {
	fake.CodecData
}

func (self SpeexCodecData) PacketDuration(data []byte) (time.Duration, error) {
	// libavcodec/libspeexdec.c
	// samples = samplerate/50
	// duration = 0.02s
	return time.Millisecond*20, nil
}

func NewSpeexCodecData(sr int, cl av.ChannelLayout) SpeexCodecData {
	codec := SpeexCodecData{}
	codec.CodecType_ = av.SPEEX
	codec.SampleFormat_ = av.S16
	codec.SampleRate_ = sr
	codec.ChannelLayout_ = cl
	return codec
}



================================================
FILE: codec/fake/fake.go
================================================
package fake

import (
	"github.com/nareix/joy4/av"
)

type CodecData struct {
	CodecType_ av.CodecType
	SampleRate_ int
	SampleFormat_ av.SampleFormat
	ChannelLayout_ av.ChannelLayout
}

func (self CodecData) Type() av.CodecType {
	return self.CodecType_
}

func (self CodecData) SampleFormat() av.SampleFormat {
	return self.SampleFormat_
}

func (self CodecData) ChannelLayout() av.ChannelLayout {
	return self.ChannelLayout_
}

func (self CodecData) SampleRate() int {
	return self.SampleRate_
}



================================================
FILE: codec/h264parser/parser.go
================================================

package h264parser

import (
	"github.com/nareix/joy4/av"
	"github.com/nareix/joy4/utils/bits"
	"github.com/nareix/joy4/utils/bits/pio"
	"fmt"
	"bytes"
)

const (
	NALU_SEI = 6
	NALU_PPS = 7
	NALU_SPS = 8
	NALU_AUD = 9
)

func IsDataNALU(b []byte) bool {
	typ := b[0] & 0x1f
	return typ >= 1 && typ <= 5
}

/*
From: http://stackoverflow.com/questions/24884827/possible-locations-for-sequence-picture-parameter-sets-for-h-264-stream

First off, it's important to understand that there is no single standard H.264 elementary bitstream format. The specification document does contain an Annex, specifically Annex B, that describes one possible format, but it is not an actual requirement. The standard specifies how video is encoded into individual packets. How these packets are stored and transmitted is left open to the integrator.

1. Annex B
Network Abstraction Layer Units
The packets are called Network Abstraction Layer Units. Often abbreviated NALU (or sometimes just NAL) each packet can be individually parsed and processed. The first byte of each NALU contains the NALU type, specifically bits 3 through 7. (bit 0 is always off, and bits 1-2 indicate whether a NALU is referenced by another NALU).

There are 19 different NALU types defined separated into two categories, VCL and non-VCL:

VCL, or Video Coding Layer packets contain the actual visual information.
Non-VCLs contain metadata that may or may not be required to decode the video.
A single NALU, or even a VCL NALU is NOT the same thing as a frame. A frame can be ‘sliced’ into several NALUs. Just like you can slice a pizza. One or more slices are then virtually grouped into a Access Units (AU) that contain one frame. Slicing does come at a slight quality cost, so it is not often used.

Below is a table of all defined NALUs.

0      Unspecified                                                    non-VCL
1      Coded slice of a non-IDR picture                               VCL
2      Coded slice data partition A                                   VCL
3      Coded slice data partition B                                   VCL
4      Coded slice data partition C                                   VCL
5      Coded slice of an IDR picture                                  VCL
6      Supplemental enhancement information (SEI)                     non-VCL
7      Sequence parameter set                                         non-VCL
8      Picture parameter set                                          non-VCL
9      Access unit delimiter                                          non-VCL
10     End of sequence                                                non-VCL
11     End of stream                                                  non-VCL
12     Filler data                                                    non-VCL
13     Sequence parameter set extension                               non-VCL
14     Prefix NAL unit                                                non-VCL
15     Subset sequence parameter set                                  non-VCL
16     Depth parameter set                                            non-VCL
17..18 Reserved                                                       non-VCL
19     Coded slice of an auxiliary coded picture without partitioning non-VCL
20     Coded slice extension                                          non-VCL
21     Coded slice extension for depth view components                non-VCL
22..23 Reserved                                                       non-VCL
24..31 Unspecified                                                    non-VCL
There are a couple of NALU types where having knowledge of may be helpful later.

Sequence Parameter Set (SPS). This non-VCL NALU contains information required to configure the decoder such as profile, level, resolution, frame rate.
Picture Parameter Set (PPS). Similar to the SPS, this non-VCL contains information on entropy coding mode, slice groups, motion prediction and deblocking filters.
Instantaneous Decoder Refresh (IDR). This VCL NALU is a self contained image slice. That is, an IDR can be decoded and displayed without referencing any other NALU save SPS and PPS.
Access Unit Delimiter (AUD). An AUD is an optional NALU that can be use to delimit frames in an elementary stream. It is not required (unless otherwise stated by the container/protocol, like TS), and is often not included in order to save space, but it can be useful to finds the start of a frame without having to fully parse each NALU.
NALU Start Codes
A NALU does not contain is its size. Therefore simply concatenating the NALUs to create a stream will not work because you will not know where one stops and the next begins.

The Annex B specification solves this by requiring ‘Start Codes’ to precede each NALU. A start code is 2 or 3 0x00 bytes followed with a 0x01 byte. e.g. 0x000001 or 0x00000001.

The 4 byte variation is useful for transmission over a serial connection as it is trivial to byte align the stream by looking for 31 zero bits followed by a one. If the next bit is 0 (because every NALU starts with a 0 bit), it is the start of a NALU. The 4 byte variation is usually only used for signaling random access points in the stream such as a SPS PPS AUD and IDR Where as the 3 byte variation is used everywhere else to save space.

Emulation Prevention Bytes
Start codes work because the four byte sequences 0x000000, 0x000001, 0x000002 and 0x000003 are illegal within a non-RBSP NALU. So when creating a NALU, care is taken to escape these values that could otherwise be confused with a start code. This is accomplished by inserting an ‘Emulation Prevention’ byte 0x03, so that 0x000001 becomes 0x00000301.

When decoding, it is important to look for and ignore emulation prevention bytes. Because emulation prevention bytes can occur almost anywhere within a NALU, it is often more convenient in documentation to assume they have already been removed. A representation without emulation prevention bytes is called Raw Byte Sequence Payload (RBSP).

Example
Let's look at a complete example.

0x0000 | 00 00 00 01 67 64 00 0A AC 72 84 44 26 84 00 00
0x0010 | 03 00 04 00 00 03 00 CA 3C 48 96 11 80 00 00 00
0x0020 | 01 68 E8 43 8F 13 21 30 00 00 01 65 88 81 00 05
0x0030 | 4E 7F 87 DF 61 A5 8B 95 EE A4 E9 38 B7 6A 30 6A
0x0040 | 71 B9 55 60 0B 76 2E B5 0E E4 80 59 27 B8 67 A9
0x0050 | 63 37 5E 82 20 55 FB E4 6A E9 37 35 72 E2 22 91
0x0060 | 9E 4D FF 60 86 CE 7E 42 B7 95 CE 2A E1 26 BE 87
0x0070 | 73 84 26 BA 16 36 F4 E6 9F 17 DA D8 64 75 54 B1
0x0080 | F3 45 0C 0B 3C 74 B3 9D BC EB 53 73 87 C3 0E 62
0x0090 | 47 48 62 CA 59 EB 86 3F 3A FA 86 B5 BF A8 6D 06
0x00A0 | 16 50 82 C4 CE 62 9E 4E E6 4C C7 30 3E DE A1 0B
0x00B0 | D8 83 0B B6 B8 28 BC A9 EB 77 43 FC 7A 17 94 85
0x00C0 | 21 CA 37 6B 30 95 B5 46 77 30 60 B7 12 D6 8C C5
0x00D0 | 54 85 29 D8 69 A9 6F 12 4E 71 DF E3 E2 B1 6B 6B
0x00E0 | BF 9F FB 2E 57 30 A9 69 76 C4 46 A2 DF FA 91 D9
0x00F0 | 50 74 55 1D 49 04 5A 1C D6 86 68 7C B6 61 48 6C
0x0100 | 96 E6 12 4C 27 AD BA C7 51 99 8E D0 F0 ED 8E F6
0x0110 | 65 79 79 A6 12 A1 95 DB C8 AE E3 B6 35 E6 8D BC
0x0120 | 48 A3 7F AF 4A 28 8A 53 E2 7E 68 08 9F 67 77 98
0x0130 | 52 DB 50 84 D6 5E 25 E1 4A 99 58 34 C7 11 D6 43
0x0140 | FF C4 FD 9A 44 16 D1 B2 FB 02 DB A1 89 69 34 C2
0x0150 | 32 55 98 F9 9B B2 31 3F 49 59 0C 06 8C DB A5 B2
0x0160 | 9D 7E 12 2F D0 87 94 44 E4 0A 76 EF 99 2D 91 18
0x0170 | 39 50 3B 29 3B F5 2C 97 73 48 91 83 B0 A6 F3 4B
0x0180 | 70 2F 1C 8F 3B 78 23 C6 AA 86 46 43 1D D7 2A 23
0x0190 | 5E 2C D9 48 0A F5 F5 2C D1 FB 3F F0 4B 78 37 E9
0x01A0 | 45 DD 72 CF 80 35 C3 95 07 F3 D9 06 E5 4A 58 76
0x01B0 | 03 6C 81 20 62 45 65 44 73 BC FE C1 9F 31 E5 DB
0x01C0 | 89 5C 6B 79 D8 68 90 D7 26 A8 A1 88 86 81 DC 9A
0x01D0 | 4F 40 A5 23 C7 DE BE 6F 76 AB 79 16 51 21 67 83
0x01E0 | 2E F3 D6 27 1A 42 C2 94 D1 5D 6C DB 4A 7A E2 CB
0x01F0 | 0B B0 68 0B BE 19 59 00 50 FC C0 BD 9D F5 F5 F8
0x0200 | A8 17 19 D6 B3 E9 74 BA 50 E5 2C 45 7B F9 93 EA
0x0210 | 5A F9 A9 30 B1 6F 5B 36 24 1E 8D 55 57 F4 CC 67
0x0220 | B2 65 6A A9 36 26 D0 06 B8 E2 E3 73 8B D1 C0 1C
0x0230 | 52 15 CA B5 AC 60 3E 36 42 F1 2C BD 99 77 AB A8
0x0240 | A9 A4 8E 9C 8B 84 DE 73 F0 91 29 97 AE DB AF D6
0x0250 | F8 5E 9B 86 B3 B3 03 B3 AC 75 6F A6 11 69 2F 3D
0x0260 | 3A CE FA 53 86 60 95 6C BB C5 4E F3

This is a complete AU containing 3 NALUs. As you can see, we begin with a Start code followed by an SPS (SPS starts with 67). Within the SPS, you will see two Emulation Prevention bytes. Without these bytes the illegal sequence 0x000000 would occur at these positions. Next you will see a start code followed by a PPS (PPS starts with 68) and one final start code followed by an IDR slice. This is a complete H.264 stream. If you type these values into a hex editor and save the file with a .264 extension, you will be able to convert it to this image:

Lena

Annex B is commonly used in live and streaming formats such as transport streams, over the air broadcasts, and DVDs. In these formats it is common to repeat the SPS and PPS periodically, usually preceding every IDR thus creating a random access point for the decoder. This enables the ability to join a stream already in progress.

2. AVCC
The other common method of storing an H.264 stream is the AVCC format. In this format, each NALU is preceded with its length (in big endian format). This method is easier to parse, but you lose the byte alignment features of Annex B. Just to complicate things, the length may be encoded using 1, 2 or 4 bytes. This value is stored in a header object. This header is often called ‘extradata’ or ‘sequence header’. Its basic format is as follows:

bits    
8   version ( always 0x01 )
8   avc profile ( sps[0][1] )
8   avc compatibility ( sps[0][2] )
8   avc level ( sps[0][3] )
6   reserved ( all bits on )
2   NALULengthSizeMinusOne
3   reserved ( all bits on )
5   number of SPS NALUs (usually 1)
repeated once per SPS:
  16         SPS size
	variable   SPS NALU data
8   number of PPS NALUs (usually 1)
repeated once per PPS
  16         PPS size
  variable   PPS NALU data

Using the same example above, the AVCC extradata will look like this:

0x0000 | 01 64 00 0A FF E1 00 19 67 64 00 0A AC 72 84 44
0x0010 | 26 84 00 00 03 00 04 00 00 03 00 CA 3C 48 96 11
0x0020 | 80 01 00 07 68 E8 43 8F 13 21 30

You will notice SPS and PPS is now stored out of band. That is, separate from the elementary stream data. Storage and transmission of this data is the job of the file container, and beyond the scope of this document. Notice that even though we are not using start codes, emulation prevention bytes are still inserted.

Additionally, there is a new variable called NALULengthSizeMinusOne. This confusingly named variable tells us how many bytes to use to store the length of each NALU. So, if NALULengthSizeMinusOne is set to 0, then each NALU is preceded with a single byte indicating its length. Using a single byte to store the size, the max size of a NALU is 255 bytes. That is obviously pretty small. Way too small for an entire key frame. Using 2 bytes gives us 64k per NALU. It would work in our example, but is still a pretty low limit. 3 bytes would be perfect, but for some reason is not universally supported. Therefore, 4 bytes is by far the most common, and it is what we used here:

0x0000 | 00 00 02 41 65 88 81 00 05 4E 7F 87 DF 61 A5 8B
0x0010 | 95 EE A4 E9 38 B7 6A 30 6A 71 B9 55 60 0B 76 2E
0x0020 | B5 0E E4 80 59 27 B8 67 A9 63 37 5E 82 20 55 FB
0x0030 | E4 6A E9 37 35 72 E2 22 91 9E 4D FF 60 86 CE 7E
0x0040 | 42 B7 95 CE 2A E1 26 BE 87 73 84 26 BA 16 36 F4
0x0050 | E6 9F 17 DA D8 64 75 54 B1 F3 45 0C 0B 3C 74 B3
0x0060 | 9D BC EB 53 73 87 C3 0E 62 47 48 62 CA 59 EB 86
0x0070 | 3F 3A FA 86 B5 BF A8 6D 06 16 50 82 C4 CE 62 9E
0x0080 | 4E E6 4C C7 30 3E DE A1 0B D8 83 0B B6 B8 28 BC
0x0090 | A9 EB 77 43 FC 7A 17 94 85 21 CA 37 6B 30 95 B5
0x00A0 | 46 77 30 60 B7 12 D6 8C C5 54 85 29 D8 69 A9 6F
0x00B0 | 12 4E 71 DF E3 E2 B1 6B 6B BF 9F FB 2E 57 30 A9
0x00C0 | 69 76 C4 46 A2 DF FA 91 D9 50 74 55 1D 49 04 5A
0x00D0 | 1C D6 86 68 7C B6 61 48 6C 96 E6 12 4C 27 AD BA
0x00E0 | C7 51 99 8E D0 F0 ED 8E F6 65 79 79 A6 12 A1 95
0x00F0 | DB C8 AE E3 B6 35 E6 8D BC 48 A3 7F AF 4A 28 8A
0x0100 | 53 E2 7E 68 08 9F 67 77 98 52 DB 50 84 D6 5E 25
0x0110 | E1 4A 99 58 34 C7 11 D6 43 FF C4 FD 9A 44 16 D1
0x0120 | B2 FB 02 DB A1 89 69 34 C2 32 55 98 F9 9B B2 31
0x0130 | 3F 49 59 0C 06 8C DB A5 B2 9D 7E 12 2F D0 87 94
0x0140 | 44 E4 0A 76 EF 99 2D 91 18 39 50 3B 29 3B F5 2C
0x0150 | 97 73 48 91 83 B0 A6 F3 4B 70 2F 1C 8F 3B 78 23
0x0160 | C6 AA 86 46 43 1D D7 2A 23 5E 2C D9 48 0A F5 F5
0x0170 | 2C D1 FB 3F F0 4B 78 37 E9 45 DD 72 CF 80 35 C3
0x0180 | 95 07 F3 D9 06 E5 4A 58 76 03 6C 81 20 62 45 65
0x0190 | 44 73 BC FE C1 9F 31 E5 DB 89 5C 6B 79 D8 68 90
0x01A0 | D7 26 A8 A1 88 86 81 DC 9A 4F 40 A5 23 C7 DE BE
0x01B0 | 6F 76 AB 79 16 51 21 67 83 2E F3 D6 27 1A 42 C2
0x01C0 | 94 D1 5D 6C DB 4A 7A E2 CB 0B B0 68 0B BE 19 59
0x01D0 | 00 50 FC C0 BD 9D F5 F5 F8 A8 17 19 D6 B3 E9 74
0x01E0 | BA 50 E5 2C 45 7B F9 93 EA 5A F9 A9 30 B1 6F 5B
0x01F0 | 36 24 1E 8D 55 57 F4 CC 67 B2 65 6A A9 36 26 D0
0x0200 | 06 B8 E2 E3 73 8B D1 C0 1C 52 15 CA B5 AC 60 3E
0x0210 | 36 42 F1 2C BD 99 77 AB A8 A9 A4 8E 9C 8B 84 DE
0x0220 | 73 F0 91 29 97 AE DB AF D6 F8 5E 9B 86 B3 B3 03
0x0230 | B3 AC 75 6F A6 11 69 2F 3D 3A CE FA 53 86 60 95
0x0240 | 6C BB C5 4E F3

An advantage to this format is the ability to configure the decoder at the start and jump into the middle of a stream. This is a common use case where the media is available on a random access medium such as a hard drive, and is therefore used in common container formats such as MP4 and MKV.
*/

var StartCodeBytes = []byte{0,0,1}
var AUDBytes = []byte{0,0,0,1,0x9,0xf0,0,0,0,1} // AUD

func CheckNALUsType(b []byte) (typ int) {
	_, typ = SplitNALUs(b)
	return
}

const (
	NALU_RAW = iota
	NALU_AVCC
	NALU_ANNEXB
)

func SplitNALUs(b []byte) (nalus [][]byte, typ int) {
	if len(b) < 4 {
		return [][]byte{b}, NALU_RAW
	}

	val3 := pio.U24BE(b)
	val4 := pio.U32BE(b)

	// maybe AVCC
	if val4 <= uint32(len(b)) {
		_val4 := val4
		_b := b[4:]
		nalus := [][]byte{}
		for {
			nalus = append(nalus, _b[:_val4])
			_b = _b[_val4:]
			if len(_b) < 4 {
				break
			}
			_val4 = pio.U32BE(_b)
			_b = _b[4:]
			if _val4 > uint32(len(_b)) {
				break
			}
		}
		if len(_b) == 0 {
			return nalus, NALU_AVCC
		}
	}

	// is Annex B
	if val3 == 1 || val4 == 1 {
		_val3 := val3
		_val4 := val4
		start := 0
		pos := 0
		for {
			if start != pos {
				nalus = append(nalus, b[start:pos])
			}
			if _val3 == 1 {
				pos += 3
			} else if _val4 == 1 {
				pos += 4
			}
			start = pos
			if start == len(b) {
				break
			}
			_val3 = 0
			_val4 = 0
			for pos < len(b) {
				if pos+2 < len(b) && b[pos] == 0 {
					_val3 = pio.U24BE(b[pos:])
					if _val3 == 0 {
						if pos+3 < len(b) {
							_val4 = uint32(b[pos+3])
							if _val4 == 1 {
								break
							}
						}
					} else if _val3 == 1 {
						break
					}
					pos++
				} else {
					pos++
				}
			}
		}
		typ = NALU_ANNEXB
		return
	}

	return [][]byte{b}, NALU_RAW
}

type SPSInfo struct {
	ProfileIdc uint
	LevelIdc   uint

	MbWidth  uint
	MbHeight uint

	CropLeft   uint
	CropRight  uint
	CropTop    uint
	CropBottom uint

	Width  uint
	Height uint
}

func ParseSPS(data []byte) (self SPSInfo, err error) {
	r := &bits.GolombBitReader{R: bytes.NewReader(data)}

	if _, err = r.ReadBits(8); err != nil {
		return
	}

	if self.ProfileIdc, err = r.ReadBits(8); err != nil {
		return
	}

	// constraint_set0_flag-constraint_set6_flag,reserved_zero_2bits
	if _, err = r.ReadBits(8); err != nil {
		return
	}

	// level_idc
	if self.LevelIdc, err = r.ReadBits(8); err != nil {
		return
	}

	// seq_parameter_set_id
	if _, err = r.ReadExponentialGolombCode(); err != nil {
		return
	}

	if self.ProfileIdc == 100 || self.ProfileIdc == 110 ||
		self.ProfileIdc == 122 || self.ProfileIdc == 244 ||
		self.ProfileIdc == 44 || self.ProfileIdc == 83 ||
		self.ProfileIdc == 86 || self.ProfileIdc == 118 {

		var chroma_format_idc uint
		if chroma_format_idc, err = r.ReadExponentialGolombCode(); err != nil {
			return
		}

		if chroma_format_idc == 3 {
			// residual_colour_transform_flag
			if _, err = r.ReadBit(); err != nil {
				return
			}
		}

		// bit_depth_luma_minus8
		if _, err = r.ReadExponentialGolombCode(); err != nil {
			return
		}
		// bit_depth_chroma_minus8
		if _, err = r.ReadExponentialGolombCode(); err != nil {
			return
		}
		// qpprime_y_zero_transform_bypass_flag
		if _, err = r.ReadBit(); err != nil {
			return
		}

		var seq_scaling_matrix_present_flag uint
		if seq_scaling_matrix_present_flag, err = r.ReadBit(); err != nil {
			return
		}

		if seq_scaling_matrix_present_flag != 0 {
			for i := 0; i < 8; i++ {
				var seq_scaling_list_present_flag uint
				if seq_scaling_list_present_flag, err = r.ReadBit(); err != nil {
					return
				}
				if seq_scaling_list_present_flag != 0 {
					var sizeOfScalingList uint
					if i < 6 {
						sizeOfScalingList = 16
					} else {
						sizeOfScalingList = 64
					}
					lastScale := uint(8)
					nextScale := uint(8)
					for j := uint(0); j < sizeOfScalingList; j++ {
						if nextScale != 0 {
							var delta_scale uint
							if delta_scale, err = r.ReadSE(); err != nil {
								return
							}
							nextScale = (lastScale + delta_scale + 256) % 256
						}
						if nextScale != 0 {
							lastScale = nextScale
						}
					}
				}
			}
		}
	}

	// log2_max_frame_num_minus4
	if _, err = r.ReadExponentialGolombCode(); err != nil {
		return
	}

	var pic_order_cnt_type uint
	if pic_order_cnt_type, err = r.ReadExponentialGolombCode(); err != nil {
		return
	}
	if pic_order_cnt_type == 0 {
		// log2_max_pic_order_cnt_lsb_minus4
		if _, err = r.ReadExponentialGolombCode(); err != nil {
			return
		}
	} else if pic_order_cnt_type == 1 {
		// delta_pic_order_always_zero_flag
		if _, err = r.ReadBit(); err != nil {
			return
		}
		// offset_for_non_ref_pic
		if _, err = r.ReadSE(); err != nil {
			return
		}
		// offset_for_top_to_bottom_field
		if _, err = r.ReadSE(); err != nil {
			return
		}
		var num_ref_frames_in_pic_order_cnt_cycle uint
		if num_ref_frames_in_pic_order_cnt_cycle, err = r.ReadExponentialGolombCode(); err != nil {
			return
		}
		for i := uint(0); i < num_ref_frames_in_pic_order_cnt_cycle; i++ {
			if _, err = r.ReadSE(); err != nil {
				return
			}
		}
	}

	// max_num_ref_frames
	if _, err = r.ReadExponentialGolombCode(); err != nil {
		return
	}

	// gaps_in_frame_num_value_allowed_flag
	if _, err = r.ReadBit(); err != nil {
		return
	}

	if self.MbWidth, err = r.ReadExponentialGolombCode(); err != nil {
		return
	}
	self.MbWidth++

	if self.MbHeight, err = r.ReadExponentialGolombCode(); err != nil {
		return
	}
	self.MbHeight++

	var frame_mbs_only_flag uint
	if frame_mbs_only_flag, err = r.ReadBit(); err != nil {
		return
	}
	if frame_mbs_only_flag == 0 {
		// mb_adaptive_frame_field_flag
		if _, err = r.ReadBit(); err != nil {
			return
		}
	}

	// direct_8x8_inference_flag
	if _, err = r.ReadBit(); err != nil {
		return
	}

	var frame_cropping_flag uint
	if frame_cropping_flag, err = r.ReadBit(); err != nil {
		return
	}
	if frame_cropping_flag != 0 {
		if self.CropLeft, err = r.ReadExponentialGolombCode(); err != nil {
			return
		}
		if self.CropRight, err = r.ReadExponentialGolombCode(); err != nil {
			return
		}
		if self.CropTop, err = r.ReadExponentialGolombCode(); err != nil {
			return
		}
		if self.CropBottom, err = r.ReadExponentialGolombCode(); err != nil {
			return
		}
	}

	self.Width = (self.MbWidth * 16) - self.CropLeft*2 - self.CropRight*2
	self.Height = ((2 - frame_mbs_only_flag) * self.MbHeight * 16) - self.CropTop*2 - self.CropBottom*2

	return
}

type CodecData struct {
	Record []byte
	RecordInfo AVCDecoderConfRecord
	SPSInfo SPSInfo
}

func (self CodecData) Type() av.CodecType {
	return av.H264
}

func (self CodecData) AVCDecoderConfRecordBytes() []byte {
	return self.Record
}

func (self CodecData) SPS() []byte {
	return self.RecordInfo.SPS[0]
}

func (self CodecData) PPS() []byte {
	return self.RecordInfo.PPS[0]
}

func (self CodecData) Width() int {
	return int(self.SPSInfo.Width)
}

func (self CodecData) Height() int {
	return int(self.SPSInfo.Height)
}

func NewCodecDataFromAVCDecoderConfRecord(record []byte) (self CodecData, err error) {
	self.Record = record
	if _, err = (&self.RecordInfo).Unmarshal(record); err != nil {
		return
	}
	if len(self.RecordInfo.SPS) == 0 {
		err = fmt.Errorf("h264parser: no SPS found in AVCDecoderConfRecord")
		return
	}
	if len(self.RecordInfo.PPS) == 0 {
		err = fmt.Errorf("h264parser: no PPS found in AVCDecoderConfRecord")
		return
	}
	if self.SPSInfo, err = ParseSPS(self.RecordInfo.SPS[0]); err != nil {
		err = fmt.Errorf("h264parser: parse SPS failed(%s)", err)
		return
	}
	return
}

func NewCodecDataFromSPSAndPPS(sps, pps []byte) (self CodecData, err error) {
	recordinfo := AVCDecoderConfRecord{}
	recordinfo.AVCProfileIndication = sps[1]
	recordinfo.ProfileCompatibility = sps[2]
	recordinfo.AVCLevelIndication = sps[3]
	recordinfo.SPS = [][]byte{sps}
	recordinfo.PPS = [][]byte{pps}
	recordinfo.LengthSizeMinusOne = 3

	buf := make([]byte, recordinfo.Len())
	recordinfo.Marshal(buf)

	self.RecordInfo = recordinfo
	self.Record = buf

	if self.SPSInfo, err = ParseSPS(sps); err != nil {
		return
	}
	return
}

type AVCDecoderConfRecord struct {
	AVCProfileIndication uint8
	ProfileCompatibility uint8
	AVCLevelIndication   uint8
	LengthSizeMinusOne   uint8
	SPS                  [][]byte
	PPS                  [][]byte
}

var ErrDecconfInvalid = fmt.Errorf("h264parser: AVCDecoderConfRecord invalid")

func (self *AVCDecoderConfRecord) Unmarshal(b []byte) (n int, err error) {
	if len(b) < 7 {
		err = ErrDecconfInvalid
		return
	}

	self.AVCProfileIndication = b[1]
	self.ProfileCompatibility = b[2]
	self.AVCLevelIndication = b[3]
	self.LengthSizeMinusOne = b[4]&0x03
	spscount := int(b[5]&0x1f)
	n += 6

	for i := 0; i < spscount; i++ {
		if len(b) < n+2 {
			err = ErrDecconfInvalid
			return
		}
		spslen := int(pio.U16BE(b[n:]))
		n += 2

		if len(b) < n+spslen {
			err = ErrDecconfInvalid
			return
		}
		self.SPS = append(self.SPS, b[n:n+spslen])
		n += spslen
	}

	if len(b) < n+1 {
		err = ErrDecconfInvalid
		return
	}
	ppscount := int(b[n])
	n++

	for i := 0; i < ppscount; i++ {
		if len(b) < n+2 {
			err = ErrDecconfInvalid
			return
		}
		ppslen := int(pio.U16BE(b[n:]))
		n += 2

		if len(b) < n+ppslen {
			err = ErrDecconfInvalid
			return
		}
		self.PPS = append(self.PPS, b[n:n+ppslen])
		n += ppslen
	}

	return
}

func (self AVCDecoderConfRecord) Len() (n int) {
	n = 7
	for _, sps := range self.SPS {
		n += 2+len(sps)
	}
	for _, pps := range self.PPS {
		n += 2+len(pps)
	}
	return
}

func (self AVCDecoderConfRecord) Marshal(b []byte) (n int) {
	b[0] = 1
	b[1] = self.AVCProfileIndication
	b[2] = self.ProfileCompatibility
	b[3] = self.AVCLevelIndication
	b[4] = self.LengthSizeMinusOne|0xfc
	b[5] = uint8(len(self.SPS))|0xe0
	n += 6

	for _, sps := range self.SPS {
		pio.PutU16BE(b[n:], uint16(len(sps)))
		n += 2
		copy(b[n:], sps)
		n += len(sps)
	}

	b[n] = uint8(len(self.PPS))
	n++

	for _, pps := range self.PPS {
		pio.PutU16BE(b[n:], uint16(len(pps)))
		n += 2
		copy(b[n:], pps)
		n += len(pps)
	}

	return
}

type SliceType uint

func (self SliceType) String() string {
	switch self {
	case SLICE_P:
		return "P"
	case SLICE_B:
		return "B"
	case SLICE_I:
		return "I"
	}
	return ""
}

const (
	SLICE_P = iota+1
	SLICE_B
	SLICE_I
)

func ParseSliceHeaderFromNALU(packet []byte) (sliceType SliceType, err error) {

	if len(packet) <= 1 {
		err = fmt.Errorf("h264parser: packet too short to parse slice header")
		return
	}

	nal_unit_type := packet[0]&0x1f
	switch nal_unit_type {
	case 1,2,5,19:
		// slice_layer_without_partitioning_rbsp
		// slice_data_partition_a_layer_rbsp

	default:
		err = fmt.Errorf("h264parser: nal_unit_type=%d has no slice header", nal_unit_type)
		return
	}

	r := &bits.GolombBitReader{R: bytes.NewReader(packet[1:])}

	// first_mb_in_slice
	if _, err = r.ReadExponentialGolombCode(); err != nil {
		return
	}

	// slice_type
	var u uint
	if u, err = r.ReadExponentialGolombCode(); err != nil {
		return
	}

	switch u {
	case 0,3,5,8:
		sliceType = SLICE_P
	case 1,6:
		sliceType = SLICE_B
	case 2,4,7,9:
		sliceType = SLICE_I
	default:
		err = fmt.Errorf("h264parser: slice_type=%d invalid", u)
		return
	}

	return
}



================================================
FILE: codec/h264parser/parser_test.go
================================================

package h264parser

import (
	"testing"
	"encoding/hex"
)

func TestParser(t *testing.T) {
	var ok bool
	var nalus [][]byte

	annexbFrame, _ := hex.DecodeString("00000001223322330000000122332233223300000133000001000001")
	nalus, ok = SplitNALUs(annexbFrame)
	t.Log(ok, len(nalus))

	avccFrame, _ := hex.DecodeString(
		"00000008aabbccaabbccaabb00000001aa",
	)
	nalus, ok = SplitNALUs(avccFrame)
	t.Log(ok, len(nalus))
}



================================================
FILE: doc.go
================================================

// Package joy4 is a Golang audio/video library and streaming server.
// JOY4 is powerful library written in golang, well-designed interface makes a few lines 
// of code can do a lot of things such as reading, writing, transcoding among 
// variety media formats, or setting up high-performance live streaming server.
package joy4


================================================
FILE: examples/audio_decode/main.go
================================================

package main

import (
	"github.com/nareix/joy4/av"
	"github.com/nareix/joy4/format"
	"github.com/nareix/joy4/av/avutil"
	"github.com/nareix/joy4/cgo/ffmpeg"
)

// need ffmpeg installed

func init() {
	format.RegisterAll()
}

func main() {
	file, _ := avutil.Open("projectindex.flv")
	streams, _ := file.Streams()
	var dec *ffmpeg.AudioDecoder

	for _, stream := range streams {
		if stream.Type() == av.AAC {
			dec, _ = ffmpeg.NewAudioDecoder(stream.(av.AudioCodecData))
		}
	}

	for i := 0; i < 10; i++ {
		pkt, _ := file.ReadPacket()
		if streams[pkt.Idx].Type() == av.AAC {
			ok, frame, _ := dec.Decode(pkt.Data)
			if ok {
				println("decode samples", frame.SampleCount)
			}
		}
	}

	file.Close()
}



================================================
FILE: examples/http_flv_and_rtmp_server/main.go
================================================
package main

import (
	"sync"
	"io"
	"net/http"
	"github.com/nareix/joy4/format"
	"github.com/nareix/joy4/av/avutil"
	"github.com/nareix/joy4/av/pubsub"
	"github.com/nareix/joy4/format/rtmp"
	"github.com/nareix/joy4/format/flv"
)

func init() {
	format.RegisterAll()
}

type writeFlusher struct {
	httpflusher http.Flusher
	io.Writer
}

func (self writeFlusher) Flush() error {
	self.httpflusher.Flush()
	return nil
}

func main() {
	server := &rtmp.Server{}

	l := &sync.RWMutex{}
	type Channel struct {
		que *pubsub.Queue
	}
	channels := map[string]*Channel{}

	server.HandlePlay = func(conn *rtmp.Conn) {
		l.RLock()
		ch := channels[conn.URL.Path]
		l.RUnlock()

		if ch != nil {
			cursor := ch.que.Latest()
			avutil.CopyFile(conn, cursor)
		}
	}

	server.HandlePublish = func(conn *rtmp.Conn) {
		streams, _ := conn.Streams()

		l.Lock()
		ch := channels[conn.URL.Path]
		if ch == nil {
			ch = &Channel{}
			ch.que = pubsub.NewQueue()
			ch.que.WriteHeader(streams)
			channels[conn.URL.Path] = ch
		} else {
			ch = nil
		}
		l.Unlock()
		if ch == nil {
			return
		}

		avutil.CopyPackets(ch.que, conn)

		l.Lock()
		delete(channels, conn.URL.Path)
		l.Unlock()
		ch.que.Close()
	}

	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
		l.RLock()
		ch := channels[r.URL.Path]
		l.RUnlock()

		if ch != nil {
			w.Header().Set("Content-Type", "video/x-flv")
			w.Header().Set("Transfer-Encoding", "chunked")		
			w.Header().Set("Access-Control-Allow-Origin", "*")
			w.WriteHeader(200)
			flusher := w.(http.Flusher)
			flusher.Flush()

			muxer := flv.NewMuxerWriteFlusher(writeFlusher{httpflusher: flusher, Writer: w})
			cursor := ch.que.Latest()

			avutil.CopyFile(muxer, cursor)
		} else {
			http.NotFound(w, r)
		}
	})

	go http.ListenAndServe(":8089", nil)

	server.ListenAndServe()

	// ffmpeg -re -i movie.flv -c copy -f flv rtmp://localhost/movie
	// ffmpeg -f avfoundation -i "0:0" .... -f flv rtmp://localhost/screen
	// ffplay http://localhost:8089/movie
	// ffplay http://localhost:8089/screen
}


================================================
FILE: examples/open_probe_file/main.go
================================================
package main

import (
	"fmt"
	"github.com/nareix/joy4/av"
	"github.com/nareix/joy4/av/avutil"
	"github.com/nareix/joy4/format"
)

func init() {
	format.RegisterAll()
}

func main() {
	file, _ := avutil.Open("projectindex.flv")

	streams, _ := file.Streams()
	for _, stream := range streams {
		if stream.Type().IsAudio() {
			astream := stream.(av.AudioCodecData)
			fmt.Println(astream.Type(), astream.SampleRate(), astream.SampleFormat(), astream.ChannelLayout())
		} else if stream.Type().IsVideo() {
			vstream := stream.(av.VideoCodecData)
			fmt.Println(vstream.Type(), vstream.Width(), vstream.Height())
		}
	}

	for i := 0; i < 10; i++ {
		var pkt av.Packet
		var err error
		if pkt, err = file.ReadPacket(); err != nil {
			break
		}
		fmt.Println("pkt", i, streams[pkt.Idx].Type(), "len", len(pkt.Data), "keyframe", pkt.IsKeyFrame)
	}

	file.Close()
}



================================================
FILE: examples/rtmp_publish/main.go
================================================
package main

import (
	"github.com/nareix/joy4/av/pktque"
	"github.com/nareix/joy4/format"
	"github.com/nareix/joy4/av/avutil"
	"github.com/nareix/joy4/format/rtmp"
)

func init() {
	format.RegisterAll()
}

// as same as: ffmpeg -re -i projectindex.flv -c copy -f flv rtmp://localhost:1936/app/publish

func main() {
	file, _ := avutil.Open("projectindex.flv")
	conn, _ := rtmp.Dial("rtmp://localhost:1936/app/publish")
	// conn, _ := avutil.Create("rtmp://localhost:1936/app/publish")

	demuxer := &pktque.FilterDemuxer{Demuxer: file, Filter: &pktque.Walltime{}}
	avutil.CopyFile(conn, demuxer)

	file.Close()
	conn.Close()
}



================================================
FILE: examples/rtmp_server_channels/main.go
================================================
package main

import (
	"fmt"
	"github.com/nareix/joy4/av"
	"github.com/nareix/joy4/av/avutil"
	"github.com/nareix/joy4/av/pktque"
	"github.com/nareix/joy4/av/pubsub"
	"github.com/nareix/joy4/format"
	"github.com/nareix/joy4/format/rtmp"
	"sync"
	"time"
)

func init() {
	format.RegisterAll()
}

type FrameDropper struct {
	Interval     int
	n            int
	skipping     bool
	DelaySkip    time.Duration
	lasttime     time.Time
	lastpkttime  time.Duration
	delay        time.Duration
	SkipInterval int
}

func (self *FrameDropper) ModifyPacket(pkt *av.Packet, streams []av.CodecData, videoidx int, audioidx int) (drop bool, err error) {
	if self.DelaySkip != 0 && pkt.Idx == int8(videoidx) {
		now := time.Now()
		if !self.lasttime.IsZero() {
			realdiff := now.Sub(self.lasttime)
			pktdiff := pkt.Time - self.lastpkttime
			self.delay += realdiff - pktdiff
		}
		self.lasttime = time.Now()
		self.lastpkttime = pkt.Time

		if !self.skipping {
			if self.delay > self.DelaySkip {
				self.skipping = true
				self.delay = 0
			}
		} else {
			if pkt.IsKeyFrame {
				self.skipping = false
			}
		}
		if self.skipping {
			drop = true
		}

		if self.SkipInterval != 0 && pkt.IsKeyFrame {
			if self.n == self.SkipInterval {
				self.n = 0
				self.skipping = true
			}
			self.n++
		}
	}

	if self.Interval != 0 {
		if self.n >= self.Interval && pkt.Idx == int8(videoidx) && !pkt.IsKeyFrame {
			drop = true
			self.n = 0
		}
		self.n++
	}

	return
}

func main() {
	server := &rtmp.Server{}

	l := &sync.RWMutex{}
	type Channel struct {
		que *pubsub.Queue
	}
	channels := map[string]*Channel{}

	server.HandlePlay = func(conn *rtmp.Conn) {
		l.RLock()
		ch := channels[conn.URL.Path]
		l.RUnlock()

		if ch != nil {
			cursor := ch.que.Latest()
			query := conn.URL.Query()

			if q := query.Get("delaygop"); q != "" {
				n := 0
				fmt.Sscanf(q, "%d", &n)
				cursor = ch.que.DelayedGopCount(n)
			} else if q := query.Get("delaytime"); q != "" {
				dur, _ := time.ParseDuration(q)
				cursor = ch.que.DelayedTime(dur)
			}

			filters := pktque.Filters{}

			if q := query.Get("waitkey"); q != "" {
				filters = append(filters, &pktque.WaitKeyFrame{})
			}

			filters = append(filters, &pktque.FixTime{StartFromZero: true, MakeIncrement: true})

			if q := query.Get("framedrop"); q != "" {
				n := 0
				fmt.Sscanf(q, "%d", &n)
				filters = append(filters, &FrameDropper{Interval: n})
			}

			if q := query.Get("delayskip"); q != "" {
				dur, _ := time.ParseDuration(q)
				skipper := &FrameDropper{DelaySkip: dur}
				if q := query.Get("skipinterval"); q != "" {
					n := 0
					fmt.Sscanf(q, "%d", &n)
					skipper.SkipInterval = n
				}
				filters = append(filters, skipper)
			}

			demuxer := &pktque.FilterDemuxer{
				Filter:  filters,
				Demuxer: cursor,
			}

			avutil.CopyFile(conn, demuxer)
		}
	}

	server.HandlePublish = func(conn *rtmp.Conn) {
		l.Lock()
		ch := channels[conn.URL.Path]
		if ch == nil {
			ch = &Channel{}
			ch.que = pubsub.NewQueue()
			query := conn.URL.Query()
			if q := query.Get("cachegop"); q != "" {
				var n int
				fmt.Sscanf(q, "%d", &n)
				ch.que.SetMaxGopCount(n)
			}
			channels[conn.URL.Path] = ch
		} else {
			ch = nil
		}
		l.Unlock()
		if ch == nil {
			return
		}

		avutil.CopyFile(ch.que, conn)

		l.Lock()
		delete(channels, conn.URL.Path)
		l.Unlock()
		ch.que.Close()
	}

	server.ListenAndServe()

	// ffmpeg -re -i movie.flv -c copy -f flv rtmp://localhost/movie
	// ffmpeg -f avfoundation -i "0:0" .... -f flv rtmp://localhost/screen

	// with cache size options

	// ffplay rtmp://localhost/movie
	// ffplay rtmp://localhost/screen
	// ffplay rtmp://localhost/movie?delaytime=5s
	// ffplay rtmp://localhost/movie?delaytime=10s&waitkey=true
	// ffplay rtmp://localhost/movie?delaytime=20s

	// ffmpeg -re -i movie.flv -c copy -f flv rtmp://localhost/movie?cachegop=2
	// ffmpeg -re -i movie.flv -c copy -f flv rtmp://localhost/movie?cachegop=1
}


================================================
FILE: examples/rtmp_server_proxy/main.go
================================================
package main

import (
	"fmt"
	"strings"
	"github.com/nareix/joy4/format"
	"github.com/nareix/joy4/av/avutil"
	"github.com/nareix/joy4/format/rtmp"
)

func init() {
	format.RegisterAll()
}

func main() {
	server := &rtmp.Server{}

	server.HandlePlay = func(conn *rtmp.Conn) {
		segs := strings.Split(conn.URL.Path, "/")
		url := fmt.Sprintf("%s://%s", segs[1], strings.Join(segs[2:], "/"))
		src, _ := avutil.Open(url)
		avutil.CopyFile(conn, src)
	}

	server.ListenAndServe()

	// ffplay rtmp://localhost/rtsp/192.168.1.1/camera1
	// ffplay rtmp://localhost/rtmp/live.hkstv.hk.lxdns.com/live/hks
}


================================================
FILE: examples/rtmp_server_speex_to_aac/main.go
================================================
package main

import (
	"github.com/nareix/joy4/av"
	"github.com/nareix/joy4/av/transcode"
	"github.com/nareix/joy4/format"
	"github.com/nareix/joy4/av/avutil"
	"github.com/nareix/joy4/format/rtmp"
	"github.com/nareix/joy4/cgo/ffmpeg"
)

// need ffmpeg with libspeex and libfdkaac installed
// 
// open http://www.wowza.com/resources/4.4.1/examples/WebcamRecording/FlashRTMPPlayer11/player.html
// click connect and recored
// input camera H264/SPEEX will converted H264/AAC and saved in out.ts

func init() {
	format.RegisterAll()
}

func main() {
	server := &rtmp.Server{}

	server.HandlePublish = func(conn *rtmp.Conn) {
		file, _ := avutil.Create("out.ts")

		findcodec := func(stream av.AudioCodecData, i int) (need bool, dec av.AudioDecoder, enc av.AudioEncoder, err error) {
			need = true
			dec, _ = ffmpeg.NewAudioDecoder(stream)
			enc, _ = ffmpeg.NewAudioEncoderByName("libfdk_aac")
			enc.SetSampleRate(48000)
			enc.SetChannelLayout(av.CH_STEREO)
			return
		}

		trans := &transcode.Demuxer{
			Options: transcode.Options{
				FindAudioDecoderEncoder: findcodec,
			},
			Demuxer: conn,
		}

		avutil.CopyFile(file, trans)
	}

	server.ListenAndServe()
}


================================================
FILE: examples/transcode/main.go
================================================
package main

import (
	"github.com/nareix/joy4/av"
	"github.com/nareix/joy4/av/transcode"
	"github.com/nareix/joy4/format"
	"github.com/nareix/joy4/av/avutil"
	"github.com/nareix/joy4/cgo/ffmpeg"
)

// need ffmpeg with libfdkaac installed

func init() {
	format.RegisterAll()
}

func main() {
	infile, _ := avutil.Open("speex.flv")

	findcodec := func(stream av.AudioCodecData, i int) (need bool, dec av.AudioDecoder, enc av.AudioEncoder, err error) {
		need = true
		dec, _ = ffmpeg.NewAudioDecoder(stream)
		enc, _ = ffmpeg.NewAudioEncoderByName("libfdk_aac")
		enc.SetSampleRate(stream.SampleRate())
		enc.SetChannelLayout(av.CH_STEREO)
		enc.SetBitrate(12000)
		enc.SetOption("profile", "HE-AACv2")
		return
	}

	trans := &transcode.Demuxer{
		Options: transcode.Options{
			FindAudioDecoderEncoder: findcodec,
		},
		Demuxer: infile,
	}

	outfile, _ := avutil.Create("out.ts")
	avutil.CopyFile(outfile, trans)

	outfile.Close()
	infile.Close()
	trans.Close()
}



================================================
FILE: format/aac/aac.go
================================================

package aac

import (
	"github.com/nareix/joy4/av/avutil"
	"github.com/nareix/joy4/av"
	"github.com/nareix/joy4/codec/aacparser"
	"time"
	"fmt"
	"io"
	"bufio"
)

type Muxer struct {
	w io.Writer
	config aacparser.MPEG4AudioConfig
	adtshdr []byte
}

func NewMuxer(w io.Writer) *Muxer {
	return &Muxer{
		adtshdr: make([]byte, aacparser.ADTSHeaderLength),
		w: w,
	}
}

func (self *Muxer) WriteHeader(streams []av.CodecData) (err error) {
	if len(streams) > 1 || streams[0].Type() != av.AAC {
		err = fmt.Errorf("aac: must be only one aac stream")
		return
	}
	self.config = streams[0].(aacparser.CodecData).Config
	if self.config.ObjectType > aacparser.AOT_AAC_LTP {
		err = fmt.Errorf("aac: AOT %d is not allowed in ADTS", self.config.ObjectType)
	}
	return
}

func (self *Muxer) WritePacket(pkt av.Packet) (err error) {
	aacparser.FillADTSHeader(self.adtshdr, self.config, 1024, len(pkt.Data))
	if _, err = self.w.Write(self.adtshdr); err != nil {
		return
	}
	if _, err = self.w.Write(pkt.Data); err != nil {
		return
	}
	return
}

func (self *Muxer) WriteTrailer() (err error) {
	return
}

type Demuxer struct {
	r *bufio.Reader
	config aacparser.MPEG4AudioConfig
	codecdata av.CodecData
	ts time.Duration
}

func NewDemuxer(r io.Reader) *Demuxer {
	return &Demuxer{
		r: bufio.NewReader(r),
	}
}

func (self *Demuxer) Streams() (streams []av.CodecData, err error) {
	if self.codecdata == nil {
		var adtshdr []byte
		var config aacparser.MPEG4AudioConfig
		if adtshdr, err = self.r.Peek(9); err != nil {
			return
		}
		if config, _, _, _, err = aacparser.ParseADTSHeader(adtshdr); err != nil {
			return
		}
		if self.codecdata, err = aacparser.NewCodecDataFromMPEG4AudioConfig(config); err != nil {
			return
		}
	}
	streams = []av.CodecData{self.codecdata}
	return
}

func (self *Demuxer) ReadPacket() (pkt av.Packet, err error) {
	var adtshdr []byte
	var config aacparser.MPEG4AudioConfig
	var hdrlen, framelen, samples int
	if adtshdr, err = self.r.Peek(9); err != nil {
		return
	}
	if config, hdrlen, framelen, samples, err = aacparser.ParseADTSHeader(adtshdr); err != nil {
		return
	}

	pkt.Data = make([]byte, framelen)
	if _, err = io.ReadFull(self.r, pkt.Data); err != nil {
		return
	}
	pkt.Data = pkt.Data[hdrlen:]

	pkt.Time = self.ts
	self.ts += time.Duration(samples) * time.Second / time.Duration(config.SampleRate)
	return
}

func Handler(h *avutil.RegisterHandler) {
	h.Ext = ".aac"

	h.ReaderDemuxer = func(r io.Reader) av.Demuxer {
		return NewDemuxer(r)
	}

	h.WriterMuxer = func(w io.Writer) av.Muxer {
		return NewMuxer(w)
	}

	h.Probe = func(b []byte) bool {
		_, _, _, _, err := aacparser.ParseADTSHeader(b)
		return err == nil
	}

	h.CodecTypes = []av.CodecType{av.AAC}
}


================================================
FILE: format/flv/flv.go
================================================
package flv

import (
	"bufio"
	"fmt"
	"github.com/nareix/joy4/utils/bits/pio"
	"github.com/nareix/joy4/av"
	"github.com/nareix/joy4/av/avutil"
	"github.com/nareix/joy4/codec"
	"github.com/nareix/joy4/codec/aacparser"
	"github.com/nareix/joy4/codec/fake"
	"github.com/nareix/joy4/codec/h264parser"
	"github.com/nareix/joy4/format/flv/flvio"
	"io"
)

var MaxProbePacketCount = 20

func NewMetadataByStreams(streams []av.CodecData) (metadata flvio.AMFMap, err error) {
	metadata = flvio.AMFMap{}

	for _, _stream := range streams {
		typ := _stream.Type()
		switch {
		case typ.IsVideo():
			stream := _stream.(av.VideoCodecData)
			switch typ {
			case av.H264:
				metadata["videocodecid"] = flvio.VIDEO_H264

			default:
				err = fmt.Errorf("flv: metadata: unsupported video codecType=%v", stream.Type())
				return
			}

			metadata["width"] = stream.Width()
			metadata["height"] = stream.Height()
			metadata["displayWidth"] = stream.Width()
			metadata["displayHeight"] = stream.Height()

		case typ.IsAudio():
			stream := _stream.(av.AudioCodecData)
			switch typ {
			case av.AAC:
				metadata["audiocodecid"] = flvio.SOUND_AAC

			case av.SPEEX:
				metadata["audiocodecid"] = flvio.SOUND_SPEEX

			default:
				err = fmt.Errorf("flv: metadata: unsupported audio codecType=%v", stream.Type())
				return
			}

			metadata["audiosamplerate"] = stream.SampleRate()
		}
	}

	return
}

type Prober struct {
	HasAudio, HasVideo             bool
	GotAudio, GotVideo             bool
	VideoStreamIdx, AudioStreamIdx int
	PushedCount                    int
	Streams                        []av.CodecData
	CachedPkts                     []av.Packet
}

func (self *Prober) CacheTag(_tag flvio.Tag, timestamp int32) {
	pkt, _ := self.TagToPacket(_tag, timestamp)
	self.CachedPkts = append(self.CachedPkts, pkt)
}

func (self *Prober) PushTag(tag flvio.Tag, timestamp int32) (err error) {
	self.PushedCount++

	if self.PushedCount > MaxProbePacketCount {
		err = fmt.Errorf("flv: max probe packet count reached")
		return
	}

	switch tag.Type {
	case flvio.TAG_VIDEO:
		switch tag.AVCPacketType {
		case flvio.AVC_SEQHDR:
			if !self.GotVideo {
				var stream h264parser.CodecData
				if stream, err = h264parser.NewCodecDataFromAVCDecoderConfRecord(tag.Data); err != nil {
					err = fmt.Errorf("flv: h264 seqhdr invalid")
					return
				}
				self.VideoStreamIdx = len(self.Streams)
				self.Streams = append(self.Streams, stream)
				self.GotVideo = true
			}

		case flvio.AVC_NALU:
			self.CacheTag(tag, timestamp)
		}

	case flvio.TAG_AUDIO:
		switch tag.SoundFormat {
		case flvio.SOUND_AAC:
			switch tag.AACPacketType {
			case flvio.AAC_SEQHDR:
				if !self.GotAudio {
					var stream aacparser.CodecData
					if stream, err = aacparser.NewCodecDataFromMPEG4AudioConfigBytes(tag.Data); err != nil {
						err = fmt.Errorf("flv: aac seqhdr invalid")
						return
					}
					self.AudioStreamIdx = len(self.Streams)
					self.Streams = append(self.Streams, stream)
					self.GotAudio = true
				}

			case flvio.AAC_RAW:
				self.CacheTag(tag, timestamp)
			}

		case flvio.SOUND_SPEEX:
			if !self.GotAudio {
				stream := codec.NewSpeexCodecData(16000, tag.ChannelLayout())
				self.AudioStreamIdx = len(self.Streams)
				self.Streams = append(self.Streams, stream)
				self.GotAudio = true
				self.CacheTag(tag, timestamp)
			}

		case flvio.SOUND_NELLYMOSER:
			if !self.GotAudio {
				stream := fake.CodecData{
					CodecType_:     av.NELLYMOSER,
					SampleRate_:    16000,
					SampleFormat_:  av.S16,
					ChannelLayout_: tag.ChannelLayout(),
				}
				self.AudioStreamIdx = len(self.Streams)
				self.Streams = append(self.Streams, stream)
				self.GotAudio = true
				self.CacheTag(tag, timestamp)
			}

		}
	}

	return
}

func (self *Prober) Probed() (ok bool) {
	if self.HasAudio || self.HasVideo {
		if self.HasAudio == self.GotAudio && self.HasVideo == self.GotVideo {
			return true
		}
	} else {
		if self.PushedCount == MaxProbePacketCount {
			return true
		}
	}
	return
}

func (self *Prober) TagToPacket(tag flvio.Tag, timestamp int32) (pkt av.Packet, ok bool) {
	switch tag.Type {
	case flvio.TAG_VIDEO:
		pkt.Idx = int8(self.VideoStreamIdx)
		switch tag.AVCPacketType {
		case flvio.AVC_NALU:
			ok = true
			pkt.Data = tag.Data
			pkt.CompositionTime = flvio.TsToTime(tag.CompositionTime)
			pkt.IsKeyFrame = tag.FrameType == flvio.FRAME_KEY
		}

	case flvio.TAG_AUDIO:
		pkt.Idx = int8(self.AudioStreamIdx)
		switch tag.SoundFormat {
		case flvio.SOUND_AAC:
			switch tag.AACPacketType {
			case flvio.AAC_RAW:
				ok = true
				pkt.Data = tag.Data
			}

		case flvio.SOUND_SPEEX:
			ok = true
			pkt.Data = tag.Data

		case flvio.SOUND_NELLYMOSER:
			ok = true
			pkt.Data = tag.Data
		}
	}

	pkt.Time = flvio.TsToTime(timestamp)
	return
}

func (self *Prober) Empty() bool {
	return len(self.CachedPkts) == 0
}

func (self *Prober) PopPacket() av.Packet {
	pkt := self.CachedPkts[0]
	self.CachedPkts = self.CachedPkts[1:]
	return pkt
}

func CodecDataToTag(stream av.CodecData) (_tag flvio.Tag, ok bool, err error) {
	switch stream.Type() {
	case av.H264:
		h264 := stream.(h264parser.CodecData)
		tag := flvio.Tag{
			Type:          flvio.TAG_VIDEO,
			AVCPacketType: flvio.AVC_SEQHDR,
			CodecID:       flvio.VIDEO_H264,
			Data:          h264.AVCDecoderConfRecordBytes(),
			FrameType:     flvio.FRAME_KEY,
		}
		ok = true
		_tag = tag

	case av.NELLYMOSER:
	case av.SPEEX:

	case av.AAC:
		aac := stream.(aacparser.CodecData)
		tag := flvio.Tag{
			Type:          flvio.TAG_AUDIO,
			SoundFormat:   flvio.SOUND_AAC,
			SoundRate:     flvio.SOUND_44Khz,
			AACPacketType: flvio.AAC_SEQHDR,
			Data:          aac.MPEG4AudioConfigBytes(),
		}
		switch aac.SampleFormat().BytesPerSample() {
		case 1:
			tag.SoundSize = flvio.SOUND_8BIT
		default:
			tag.SoundSize = flvio.SOUND_16BIT
		}
		switch aac.ChannelLayout().Count() {
		case 1:
			tag.SoundType = flvio.SOUND_MONO
		case 2:
			tag.SoundType = flvio.SOUND_STEREO
		}
		ok = true
		_tag = tag

	default:
		err = fmt.Errorf("flv: unspported codecType=%v", stream.Type())
		return
	}
	return
}

func PacketToTag(pkt av.Packet, stream av.CodecData) (tag flvio.Tag, timestamp int32) {
	switch stream.Type() {
	case av.H264:
		tag = flvio.Tag{
			Type:            flvio.TAG_VIDEO,
			AVCPacketType:   flvio.AVC_NALU,
			CodecID:         flvio.VIDEO_H264,
			Data:            pkt.Data,
			CompositionTime: flvio.TimeToTs(pkt.CompositionTime),
		}
		if pkt.IsKeyFrame {
			tag.FrameType = flvio.FRAME_KEY
		} else {
			tag.FrameType = flvio.FRAME_INTER
		}

	case av.AAC:
		tag = flvio.Tag{
			Type:          flvio.TAG_AUDIO,
			SoundFormat:   flvio.SOUND_AAC,
			SoundRate:     flvio.SOUND_44Khz,
			AACPacketType: flvio.AAC_RAW,
			Data:          pkt.Data,
		}
		astream := stream.(av.AudioCodecData)
		switch astream.SampleFormat().BytesPerSample() {
		case 1:
			tag.SoundSize = flvio.SOUND_8BIT
		default:
			tag.SoundSize = flvio.SOUND_16BIT
		}
		switch astream.ChannelLayout().Count() {
		case 1:
			tag.SoundType = flvio.SOUND_MONO
		case 2:
			tag.SoundType = flvio.SOUND_STEREO
		}

	case av.SPEEX:
		tag = flvio.Tag{
			Type:        flvio.TAG_AUDIO,
			SoundFormat: flvio.SOUND_SPEEX,
			Data:        pkt.Data,
		}

	case av.NELLYMOSER:
		tag = flvio.Tag{
			Type:        flvio.TAG_AUDIO,
			SoundFormat: flvio.SOUND_NELLYMOSER,
			Data:        pkt.Data,
		}
	}

	timestamp = flvio.TimeToTs(pkt.Time)
	return
}

type Muxer struct {
	bufw    writeFlusher
	b       []byte
	streams []av.CodecData
}

type writeFlusher interface {
	io.Writer
	Flush() error
}

func NewMuxerWriteFlusher(w writeFlusher) *Muxer {
	return &Muxer{
		bufw: w,
		b:    make([]byte, 256),
	}
}

func NewMuxer(w io.Writer) *Muxer {
	return NewMuxerWriteFlusher(bufio.NewWriterSize(w, pio.RecommendBufioSize))
}

var CodecTypes = []av.CodecType{av.H264, av.AAC, av.SPEEX}

func (self *Muxer) WriteHeader(streams []av.CodecData) (err error) {
	var flags uint8
	for _, stream := range streams {
		if stream.Type().IsVideo() {
			flags |= flvio.FILE_HAS_VIDEO
		} else if stream.Type().IsAudio() {
			flags |= flvio.FILE_HAS_AUDIO
		}
	}

	n := flvio.FillFileHeader(self.b, flags)
	if _, err = self.bufw.Write(self.b[:n]); err != nil {
		return
	}

	for _, stream := range streams {
		var tag flvio.Tag
		var ok bool
		if tag, ok, err = CodecDataToTag(stream); err != nil {
			return
		}
		if ok {
			if err = flvio.WriteTag(self.bufw, tag, 0, self.b); err != nil {
				return
			}
		}
	}

	self.streams = streams
	return
}

func (self *Muxer) WritePacket(pkt av.Packet) (err error) {
	stream := self.streams[pkt.Idx]
	tag, timestamp := PacketToTag(pkt, stream)

	if err = flvio.WriteTag(self.bufw, tag, timestamp, self.b); err != nil {
		return
	}
	return
}

func (self *Muxer) WriteTrailer() (err error) {
	if err = self.bufw.Flush(); err != nil {
		return
	}
	return
}

type Demuxer struct {
	prober *Prober
	bufr   *bufio.Reader
	b      []byte
	stage  int
}

func NewDemuxer(r io.Reader) *Demuxer {
	return &Demuxer{
		bufr:   bufio.NewReaderSize(r, pio.RecommendBufioSize),
		prober: &Prober{},
		b:      make([]byte, 256),
	}
}

func (self *Demuxer) prepare() (err error) {
	for self.stage < 2 {
		switch self.stage {
		case 0:
			if _, err = io.ReadFull(self.bufr, self.b[:flvio.FileHeaderLength]); err != nil {
				return
			}
			var flags uint8
			var skip int
			if flags, skip, err = flvio.ParseFileHeader(self.b); err != nil {
				return
			}
			if _, err = self.bufr.Discard(skip); err != nil {
				return
			}
			if flags&flvio.FILE_HAS_AUDIO != 0 {
				self.prober.HasAudio = true
			}
			if flags&flvio.FILE_HAS_VIDEO != 0 {
				self.prober.HasVideo = true
			}
			self.stage++

		case 1:
			for !self.prober.Probed() {
				var tag flvio.Tag
				var timestamp int32
				if tag, timestamp, err = flvio.ReadTag(self.bufr, self.b); err != nil {
					return
				}
				if err = self.prober.PushTag(tag, timestamp); err != nil {
					return
				}
			}
			self.stage++
		}
	}
	return
}

func (self *Demuxer) Streams() (streams []av.CodecData, err error) {
	if err = self.prepare(); err != nil {
		return
	}
	streams = self.prober.Streams
	return
}

func (self *Demuxer) ReadPacket() (pkt av.Packet, err error) {
	if err = self.prepare(); err != nil {
		return
	}

	if !self.prober.Empty() {
		pkt = self.prober.PopPacket()
		return
	}

	for {
		var tag flvio.Tag
		var timestamp int32
		if tag, timestamp, err = flvio.ReadTag(self.bufr, self.b); err != nil {
			return
		}

		var ok bool
		if pkt, ok = self.prober.TagToPacket(tag, timestamp); ok {
			return
		}
	}

	return
}

func Handler(h *avutil.RegisterHandler) {
	h.Probe = func(b []byte) bool {
		return b[0] == 'F' && b[1] == 'L' && b[2] == 'V'
	}

	h.Ext = ".flv"

	h.ReaderDemuxer = func(r io.Reader) av.Demuxer {
		return NewDemuxer(r)
	}

	h.WriterMuxer = func(w io.Writer) av.Muxer {
		return NewMuxer(w)
	}

	h.CodecTypes = CodecTypes
}


================================================
FILE: format/flv/flvio/amf0.go
================================================
package flvio

import (
	"strings"
	"math"
	"fmt"
	"time"
	"github.com/nareix/joy4/utils/bits/pio"
)

type AMF0ParseError struct {
	Offset int
	Message string
	Next *AMF0ParseError
}

func (self *AMF0ParseError) Error() string {
	s := []string{}
	for p := self; p != nil; p = p.Next {
		s = append(s, fmt.Sprintf("%s:%d", p.Message, p.Offset))
	}
	return "amf0 parse error: " + strings.Join(s, ",")
}

func amf0ParseErr(message string, offset int, err error) error {
	next, _ := err.(*AMF0ParseError)
	return &AMF0ParseError{
		Offset: offset,
		Message: message,
		Next: next,
	}
}

type AMFMap map[string]interface{}
type AMFArray []interface{}
type AMFECMAArray map[string]interface{}

func parseBEFloat64(b []byte) float64 {
	return math.Float64frombits(pio.U64BE(b))
}

func fillBEFloat64(b []byte, f float64) int {
	pio.PutU64BE(b, math.Float64bits(f))
	return 8
}

const lenAMF0Number = 9

func fillAMF0Number(b []byte, f float64) int {
	b[0] = numbermarker
	fillBEFloat64(b[1:], f)
	return lenAMF0Number
}

const (
	amf3undefinedmarker = iota
	amf3nullmarker
	amf3falsemarker
	amf3truemarker
	amf3integermarker
	amf3doublemarker
	amf3stringmarker
	amf3xmldocmarker
	amf3datemarker
	amf3arraymarker
	amf3objectmarker
	amf3xmlmarker
	amf3bytearraymarker
	amf3vectorintmarker
	amf3vectoruintmarker
	amf3vectordoublemarker
	amf3vectorobjectmarker
	amf3dictionarymarker
)

const (
	numbermarker = iota
	booleanmarker
	stringmarker
	objectmarker
	movieclipmarker
	nullmarker
	undefinedmarker
	referencemarker
	ecmaarraymarker
	objectendmarker
	strictarraymarker
	datemarker
	longstringmarker
	unsupportedmarker
	recordsetmarker
	xmldocumentmarker
	typedobjectmarker
	avmplusobjectmarker
)

func LenAMF0Val(_val interface{}) (n int) {
	switch val := _val.(type) {
	case int8:
		n += lenAMF0Number
	case int16:
		n += lenAMF0Number
	case int32:
		n += lenAMF0Number
	case int64:
		n += lenAMF0Number
	case int:
		n += lenAMF0Number
	case uint8:
		n += lenAMF0Number
	case uint16:
		n += lenAMF0Number
	case uint32:
		n += lenAMF0Number
	case uint64:
		n += lenAMF0Number
	case uint:
		n += lenAMF0Number
	case float32:
		n += lenAMF0Number
	case float64:
		n += lenAMF0Number

	case string:
		u := len(val)
		if u <= 65536 {
			n += 3
		} else {
			n += 5
		}
		n += int(u)

	case AMFECMAArray:
		n += 5
		for k, v := range val {
			n += 2+len(k)
			n += LenAMF0Val(v)
		}
		n += 3

	case AMFMap:
		n++
		for k, v := range val {
			if len(k) > 0 {
				n += 2+len(k)
				n += LenAMF0Val(v)
			}
		}
		n += 3

	case AMFArray:
		n += 5
		for _, v := range val {
			n += LenAMF0Val(v)
		}

	case time.Time:
		n += 1+8+2

	case bool:
		n += 2

	case nil:
		n++
	}

	return
}

func FillAMF0Val(b []byte, _val interface{}) (n int) {
	switch val := _val.(type) {
	case int8:
		n += fillAMF0Number(b[n:], float64(val))
	case int16:
		n += fillAMF0Number(b[n:], float64(val))
	case int32:
		n += fillAMF0Number(b[n:], float64(val))
	case int64:
		n += fillAMF0Number(b[n:], float64(val))
	case int:
		n += fillAMF0Number(b[n:], float64(val))
	case uint8:
		n += fillAMF0Number(b[n:], float64(val))
	case uint16:
		n += fillAMF0Number(b[n:], float64(val))
	case uint32:
		n += fillAMF0Number(b[n:], float64(val))
	case uint64:
		n += fillAMF0Number(b[n:], float64(val))
	case uint:
		n += fillAMF0Number(b[n:], float64(val))
	case float32:
		n += fillAMF0Number(b[n:], float64(val))
	case float64:
		n += fillAMF0Number(b[n:], float64(val))

	case string:
		u := len(val)
		if u <= 65536 {
			b[n] = stringmarker
			n++
			pio.PutU16BE(b[n:], uint16(u))
			n += 2
		} else {
			b[n] = longstringmarker
			n++
			pio.PutU32BE(b[n:], uint32(u))
			n += 4
		}
		copy(b[n:], []byte(val))
		n += len(val)

	case AMFECMAArray:
		b[n] = ecmaarraymarker
		n++
		pio.PutU32BE(b[n:], uint32(len(val)))
		n += 4
		for k, v := range val {
			pio.PutU16BE(b[n:], uint16(len(k)))
			n += 2
			copy(b[n:], []byte(k))
			n += len(k)
			n += FillAMF0Val(b[n:], v)
		}
		pio.PutU24BE(b[n:], 0x000009)
		n += 3

	case AMFMap:
		b[n] = objectmarker
		n++
		for k, v := range val {
			if len(k) > 0 {
				pio.PutU16BE(b[n:], uint16(len(k)))
				n += 2
				copy(b[n:], []byte(k))
				n += len(k)
				n += FillAMF0Val(b[n:], v)
			}
		}
		pio.PutU24BE(b[n:], 0x000009)
		n += 3

	case AMFArray:
		b[n] = strictarraymarker
		n++
		pio.PutU32BE(b[n:], uint32(len(val)))
		n += 4
		for _, v := range val {
			n += FillAMF0Val(b[n:], v)
		}

	case time.Time:
		b[n] = datemarker
		n++
		u := val.UnixNano()
		f := float64(u/1000000)
		n += fillBEFloat64(b[n:], f)
		pio.PutU16BE(b[n:], uint16(0))
		n += 2

	case bool:
		b[n] = booleanmarker
		n++
		var u uint8
		if val {
			u = 1
		} else {
			u = 0
		}
		b[n] = u
		n++

	case nil:
		b[n] = nullmarker
		n++
	}

	return
}


func ParseAMF0Val(b []byte) (val interface{}, n int, err error) {
	return parseAMF0Val(b, 0)
}

func parseAMF0Val(b []byte, offset int) (val interface{}, n int, err error) {
	if len(b) < n+1 {
		err = amf0ParseErr("marker", offset+n, err)
		return
	}
	marker := b[n]
	n++

	switch marker {
	case numbermarker:
		if len(b) < n+8 {
			err = amf0ParseErr("number", offset+n, err)
			return
		}
		val = parseBEFloat64(b[n:])
		n += 8

	case booleanmarker:
		if len(b) < n+1 {
			err = amf0ParseErr("boolean", offset+n, err)
			return
		}
		val = b[n] != 0
		n++

	case stringmarker:
		if len(b) < n+2 {
			err = amf0ParseErr("string.length", offset+n, err)
			return
		}
		length := int(pio.U16BE(b[n:]))
		n += 2

		if len(b) < n+length {
			err = amf0ParseErr("string.body", offset+n, err)
			return
		}
		val = string(b[n:n+length])
		n += length

	case objectmarker:
		obj := AMFMap{}
		for {
			if len(b) < n+2 {
				err = amf0ParseErr("object.key.length", offset+n, err)
				return
			}
			length := int(pio.U16BE(b[n:]))
			n += 2
			if length == 0 {
				break
			}

			if len(b) < n+length {
				err = amf0ParseErr("object.key.body", offset+n, err)
				return
			}
			okey := string(b[n:n+length])
			n += length

			var nval int
			var oval interface{}
			if oval, nval, err = parseAMF0Val(b[n:], offset+n); err != nil {
				err = amf0ParseErr("object.val", offset+n, err)
				return
			}
			n += nval

			obj[okey] = oval
		}
		if len(b) < n+1 {
			err = amf0ParseErr("object.end", offset+n, err)
			return
		}
		n++
		val = obj

	case nullmarker:
	case undefinedmarker:

	case ecmaarraymarker:
		if len(b) < n+4 {
			err = amf0ParseErr("array.count", offset+n, err)
			return
		}
		n += 4

		obj := AMFMap{}
		for {
			if len(b) < n+2 {
				err = amf0ParseErr("array.key.length", offset+n, err)
				return
			}
			length := int(pio.U16BE(b[n:]))
			n += 2

			if length == 0 {
				break
			}

			if len(b) < n+length {
				err = amf0ParseErr("array.key.body", offset+n, err)
				return
			}
			okey := string(b[n:n+length])
			n += length

			var nval int
			var oval interface{}
			if oval, nval, err = parseAMF0Val(b[n:], offset+n); err != nil {
				err = amf0ParseErr("array.val", offset+n, err)
				return
			}
			n += nval

			obj[okey] = oval
		}
		if len(b) < n+1 {
			err = amf0ParseErr("array.end", offset+n, err)
			return
		}
		n += 1
		val = obj

	case objectendmarker:
		if len(b) < n+3 {
			err = amf0ParseErr("objectend", offset+n, err)
			return
		}
		n += 3

	case strictarraymarker:
		if len(b) < n+4 {
			err = amf0ParseErr("strictarray.count", offset+n, err)
			return
		}
		count := int(pio.U32BE(b[n:]))
		n += 4

		obj := make(AMFArray, count)
		for i := 0; i < int(count); i++ {
			var nval int
			if obj[i], nval, err = parseAMF0Val(b[n:], offset+n); err != nil {
				err = amf0ParseErr("strictarray.val", offset+n, err)
				return
			}
			n += nval
		}
		val = obj

	case datemarker:
		if len(b) < n+8+2 {
			err = amf0ParseErr("date", offset+n, err)
			return
		}
		ts := parseBEFloat64(b[n:])
		n += 8+2

		val = time.Unix(int64(ts/1000), (int64(ts)%1000)*1000000)

	case longstringmarker:
		if len(b) < n+4 {
			err = amf0ParseErr("longstring.length", offset+n, err)
			return
		}
		length := int(pio.U32BE(b[n:]))
		n += 4

		if len(b) < n+length {
			err = amf0ParseErr("longstring.body", offset+n, err)
			return
		}
		val = string(b[n:n+length])
		n += length

	default:
		err = amf0ParseErr(fmt.Sprintf("invalidmarker=%d", marker), offset+n, err)
		return
	}

	return
}



================================================
FILE: format/flv/flvio/flvio.go
================================================
package flvio

import (
	"fmt"
	"github.com/nareix/joy4/utils/bits/pio"
	"github.com/nareix/joy4/av"
	"io"
	"time"
)

func TsToTime(ts int32) time.Duration {
	return time.Millisecond * time.Duration(ts)
}

func TimeToTs(tm time.Duration) int32 {
	return int32(tm / time.Millisecond)
}

const MaxTagSubHeaderLength = 16

const (
	TAG_AUDIO      = 8
	TAG_VIDEO      = 9
	TAG_SCRIPTDATA = 18
)

const (
	SOUND_MP3                   = 2
	SOUND_NELLYMOSER_16KHZ_MONO = 4
	SOUND_NELLYMOSER_8KHZ_MONO  = 5
	SOUND_NELLYMOSER            = 6
	SOUND_ALAW                  = 7
	SOUND_MULAW                 = 8
	SOUND_AAC                   = 10
	SOUND_SPEEX                 = 11

	SOUND_5_5Khz = 0
	SOUND_11Khz  = 1
	SOUND_22Khz  = 2
	SOUND_44Khz  = 3

	SOUND_8BIT  = 0
	SOUND_16BIT = 1

	SOUND_MONO   = 0
	SOUND_STEREO = 1

	AAC_SEQHDR = 0
	AAC_RAW    = 1
)

const (
	AVC_SEQHDR = 0
	AVC_NALU   = 1
	AVC_EOS    = 2

	FRAME_KEY   = 1
	FRAME_INTER = 2

	VIDEO_H264 = 7
)

type Tag struct {
	Type uint8

	/*
		SoundFormat: UB[4]
		0 = Linear PCM, platform endian
		1 = ADPCM
		2 = MP3
		3 = Linear PCM, little endian
		4 = Nellymoser 16-kHz mono
		5 = Nellymoser 8-kHz mono
		6 = Nellymoser
		7 = G.711 A-law logarithmic PCM
		8 = G.711 mu-law logarithmic PCM
		9 = reserved
		10 = AAC
		11 = Speex
		14 = MP3 8-Khz
		15 = Device-specific sound
		Formats 7, 8, 14, and 15 are reserved for internal use
		AAC is supported in Flash Player 9,0,115,0 and higher.
		Speex is supported in Flash Player 10 and higher.
	*/
	SoundFormat uint8

	/*
		SoundRate: UB[2]
		Sampling rate
		0 = 5.5-kHz For AAC: always 3
		1 = 11-kHz
		2 = 22-kHz
		3 = 44-kHz
	*/
	SoundRate uint8

	/*
		SoundSize: UB[1]
		0 = snd8Bit
		1 = snd16Bit
		Size of each sample.
		This parameter only pertains to uncompressed formats.
		Compressed formats always decode to 16 bits internally
	*/
	SoundSize uint8

	/*
		SoundType: UB[1]
		0 = sndMono
		1 = sndStereo
		Mono or stereo sound For Nellymoser: always 0
		For AAC: always 1
	*/
	SoundType uint8

	/*
		0: AAC sequence header
		1: AAC raw
	*/
	AACPacketType uint8

	/*
		1: keyframe (for AVC, a seekable frame)
		2: inter frame (for AVC, a non- seekable frame)
		3: disposable inter frame (H.263 only)
		4: generated keyframe (reserved for server use only)
		5: video info/command frame
	*/
	FrameType uint8

	/*
		1: JPEG (currently unused)
		2: Sorenson H.263
		3: Screen video
		4: On2 VP6
		5: On2 VP6 with alpha channel
		6: Screen video version 2
		7: AVC
	*/
	CodecID uint8

	/*
		0: AVC sequence header
		1: AVC NALU
		2: AVC end of sequence (lower level NALU sequence ender is not required or supported)
	*/
	AVCPacketType uint8

	CompositionTime int32

	Data []byte
}

func (self Tag) ChannelLayout() av.ChannelLayout {
	if self.SoundType == SOUND_MONO {
		return av.CH_MONO
	} else {
		return av.CH_STEREO
	}
}

func (self *Tag) audioParseHeader(b []byte) (n int, err error) {
	if len(b) < n+1 {
		err = fmt.Errorf("audiodata: parse invalid")
		return
	}

	flags := b[n]
	n++
	self.SoundFormat = flags >> 4
	self.SoundRate = (flags >> 2) & 0x3
	self.SoundSize = (flags >> 1) & 0x1
	self.SoundType = flags & 0x1

	switch self.SoundFormat {
	case SOUND_AAC:
		if len(b) < n+1 {
			err = fmt.Errorf("audiodata: parse invalid")
			return
		}
		self.AACPacketType = b[n]
		n++
	}

	return
}

func (self Tag) audioFillHeader(b []byte) (n int) {
	var flags uint8
	flags |= self.SoundFormat << 4
	flags |= self.SoundRate << 2
	flags |= self.SoundSize << 1
	flags |= self.SoundType
	b[n] = flags
	n++

	switch self.SoundFormat {
	case SOUND_AAC:
		b[n] = self.AACPacketType
		n++
	}

	return
}

func (self *Tag) videoParseHeader(b []byte) (n int, err error) {
	if len(b) < n+1 {
		err = fmt.Errorf("videodata: parse invalid")
		return
	}
	flags := b[n]
	self.FrameType = flags >> 4
	self.CodecID = flags & 0xf
	n++

	if self.FrameType == FRAME_INTER || self.FrameType == FRAME_KEY {
		if len(b) < n+4 {
			err = fmt.Errorf("videodata: parse invalid")
			return
		}
		self.AVCPacketType = b[n]
		n++

		self.CompositionTime = pio.I24BE(b[n:])
		n += 3
	}

	return
}

func (self Tag) videoFillHeader(b []byte) (n int) {
	flags := self.FrameType<<4 | self.CodecID
	b[n] = flags
	n++
	b[n] = self.AVCPacketType
	n++
	pio.PutI24BE(b[n:], self.CompositionTime)
	n += 3
	return
}

func (self Tag) FillHeader(b []byte) (n int) {
	switch self.Type {
	case TAG_AUDIO:
		return self.audioFillHeader(b)

	case TAG_VIDEO:
		return self.videoFillHeader(b)
	}

	return
}

func (self *Tag) ParseHeader(b []byte) (n int, err error) {
	switch self.Type {
	case TAG_AUDIO:
		return self.audioParseHeader(b)

	case TAG_VIDEO:
		return self.videoParseHeader(b)
	}

	return
}

const (
	// TypeFlagsReserved UB[5]
	// TypeFlagsAudio    UB[1] Audio tags are present
	// TypeFlagsReserved UB[1] Must be 0
	// TypeFlagsVideo    UB[1] Video tags are present
	FILE_HAS_AUDIO = 0x4
	FILE_HAS_VIDEO = 0x1
)

const TagHeaderLength = 11
const TagTrailerLength = 4

func ParseTagHeader(b []byte) (tag Tag, ts int32, datalen int, err error) {
	tagtype := b[0]

	switch tagtype {
	case TAG_AUDIO, TAG_VIDEO, TAG_SCRIPTDATA:
		tag = Tag{Type: tagtype}

	default:
		err = fmt.Errorf("flvio: ReadTag tagtype=%d invalid", tagtype)
		return
	}

	datalen = int(pio.U24BE(b[1:4]))

	var tslo uint32
	var tshi uint8
	tslo = pio.U24BE(b[4:7])
	tshi = b[7]
	ts = int32(tslo | uint32(tshi)<<24)

	return
}

func ReadTag(r io.Reader, b []byte) (tag Tag, ts int32, err error) {
	if _, err = io.ReadFull(r, b[:TagHeaderLength]); err != nil {
		return
	}
	var datalen int
	if tag, ts, datalen, err = ParseTagHeader(b); err != nil {
		return
	}

	data := make([]byte, datalen)
	if _, err = io.ReadFull(r, data); err != nil {
		return
	}

	var n int
	if n, err = (&tag).ParseHeader(data); err != nil {
		return
	}
	tag.Data = data[n:]

	if _, err = io.ReadFull(r, b[:4]); err != nil {
		return
	}
	return
}

func FillTagHeader(b []byte, tagtype uint8, datalen int, ts int32) (n int) {
	b[n] = tagtype
	n++
	pio.PutU24BE(b[n:], uint32(datalen))
	n += 3
	pio.PutU24BE(b[n:], uint32(ts&0xffffff))
	n += 3
	b[n] = uint8(ts >> 24)
	n++
	pio.PutI24BE(b[n:], 0)
	n += 3
	return
}

func FillTagTrailer(b []byte, datalen int) (n int) {
	pio.PutU32BE(b[n:], uint32(datalen+TagHeaderLength))
	n += 4
	return
}

func WriteTag(w io.Writer, tag Tag, ts int32, b []byte) (err error) {
	data := tag.Data

	n := tag.FillHeader(b[TagHeaderLength:])
	datalen := len(data) + n

	n += FillTagHeader(b, tag.Type, datalen, ts)

	if _, err = w.Write(b[:n]); err != nil {
		return
	}

	if _, err = w.Write(data); err != nil {
		return
	}

	n = FillTagTrailer(b, datalen)
	if _, err = w.Write(b[:n]); err != nil {
		return
	}

	return
}

const FileHeaderLength = 9

func FillFileHeader(b []byte, flags uint8) (n int) {
	// 'FLV', version 1
	pio.PutU32BE(b[n:], 0x464c5601)
	n += 4

	b[n] = flags
	n++

	// DataOffset: UI32 Offset in bytes from start of file to start of body (that is, size of header)
	// The DataOffset field usually has a value of 9 for FLV version 1.
	pio.PutU32BE(b[n:], 9)
	n += 4

	// PreviousTagSize0: UI32 Always 0
	pio.PutU32BE(b[n:], 0)
	n += 4

	return
}

func ParseFileHeader(b []byte) (flags uint8, skip int, err error) {
	flv := pio.U24BE(b[0:3])
	if flv != 0x464c56 { // 'FLV'
		err = fmt.Errorf("flvio: file header cc3 invalid")
		return
	}

	flags = b[4]

	skip = int(pio.U32BE(b[5:9])) - 9 + 4
	if skip < 0 {
		err = fmt.Errorf("flvio: file header datasize invalid")
		return
	}

	return
}


================================================
FILE: format/format.go
================================================
package format

import (
	"github.com/nareix/joy4/format/mp4"
	"github.com/nareix/joy4/format/ts"
	"github.com/nareix/joy4/format/rtmp"
	"github.com/nareix/joy4/format/rtsp"
	"github.com/nareix/joy4/format/flv"
	"github.com/nareix/joy4/format/aac"
	"github.com/nareix/joy4/av/avutil"
)

func RegisterAll() {
	avutil.DefaultHandlers.Add(mp4.Handler)
	avutil.DefaultHandlers.Add(ts.Handler)
	avutil.DefaultHandlers.Add(rtmp.Handler)
	avutil.DefaultHandlers.Add(rtsp.Handler)
	avutil.DefaultHandlers.Add(flv.Handler)
	avutil.DefaultHandlers.Add(aac.Handler)
}



================================================
FILE: format/mp4/demuxer.go
================================================
package mp4

import (
	"errors"
	"fmt"
	"io"
	"time"

	"github.com/nareix/joy4/av"
	"github.com/nareix/joy4/codec/aacparser"
	"github.com/nareix/joy4/codec/h264parser"
	"github.com/nareix/joy4/format/mp4/mp4io"
)

type Demuxer struct {
	r         io.ReadSeeker
	streams   []*Stream
	movieAtom *mp4io.Movie
}

func NewDemuxer(r io.ReadSeeker) *Demuxer {
	return &Demuxer{
		r: r,
	}
}

func (self *Demuxer) Streams() (streams []av.CodecData, err error) {
	if err = self.probe(); err != nil {
		return
	}
	for _, stream := range self.streams {
		streams = append(streams, stream.CodecData)
	}
	return
}

func (self *Demuxer) readat(pos int64, b []byte) (err error) {
	if _, err = self.r.Seek(pos, 0); err != nil {
		return
	}
	if _, err = io.ReadFull(self.r, b); err != nil {
		return
	}
	return
}

func (self *Demuxer) probe() (err error) {
	if self.movieAtom != nil {
		return
	}

	var moov *mp4io.Movie
	var atoms []mp4io.Atom

	if atoms, err = mp4io.ReadFileAtoms(self.r); err != nil {
		return
	}
	if _, err = self.r.Seek(0, 0); err != nil {
		return
	}

	for _, atom := range atoms {
		if atom.Tag() == mp4io.MOOV {
			moov = atom.(*mp4io.Movie)
		}
	}

	if moov == nil {
		err = fmt.Errorf("mp4: 'moov' atom not found")
		return
	}

	self.streams = []*Stream{}
	for i, atrack := range moov.Tracks {
		stream := &Stream{
			trackAtom: atrack,
			demuxer:   self,
			idx:       i,
		}
		if atrack.Media != nil && atrack.Media.Info != nil && atrack.Media.Info.Sample != nil {
			stream.sample = atrack.Media.Info.Sample
			stream.timeScale = int64(atrack.Media.Header.TimeScale)
		} else {
			err = fmt.Errorf("mp4: sample table not found")
			return
		}

		if avc1 := atrack.GetAVC1Conf(); avc1 != nil {
			if stream.CodecData, err = h264parser.NewCodecDataFromAVCDecoderConfRecord(avc1.Data); err != nil {
				return
			}
			self.streams = append(self.streams, stream)
		} else if esds := atrack.GetElemStreamDesc(); esds != nil {
			if stream.CodecData, err = aacparser.NewCodecDataFromMPEG4AudioConfigBytes(esds.DecConfig); err != nil {
				return
			}
			self.streams = append(self.streams, stream)
		}
	}

	self.movieAtom = moov
	return
}

func (self *Stream) setSampleIndex(index int) (err error) {
	found := false
	start := 0
	self.chunkGroupIndex = 0

	for self.chunkIndex = range self.sample.ChunkOffset.Entries {
		if self.chunkGroupIndex+1 < len(self.sample.SampleToChunk.Entries) &&
			uint32(self.chunkIndex+1) == self.sample.SampleToChunk.Entries[self.chunkGroupIndex+1].FirstChunk {
			self.chunkGroupIndex++
		}
		n := int(self.sample.SampleToChunk.Entries[self.chunkGroupIndex].SamplesPerChunk)
		if index >= start && index < start+n {
			found = true
			self.sampleIndexInChunk = index - start
			break
		}
		start += n
	}
	if !found {
		err = fmt.Errorf("mp4: stream[%d]: cannot locate sample index in chunk", self.idx)
		return
	}

	if self.sample.SampleSize.SampleSize != 0 {
		self.sampleOffsetInChunk = int64(self.sampleIndexInChunk) * int64(self.sample.SampleSize.SampleSize)
	} else {
		if index >= len(self.sample.SampleSize.Entries) {
			err = fmt.Errorf("mp4: stream[%d]: sample index out of range", self.idx)
			return
		}
		self.sampleOffsetInChunk = int64(0)
		for i := index - self.sampleIndexInChunk; i < index; i++ {
			self.sampleOffsetInChunk += int64(self.sample.SampleSize.Entries[i])
		}
	}

	self.dts = int64(0)
	start = 0
	found = false
	self.sttsEntryIndex = 0
	for self.sttsEntryIndex < len(self.sample.TimeToSample.Entries) {
		entry := self.sample.TimeToSample.Entries[self.sttsEntryIndex]
		n := int(entry.Count)
		if index >= start && index < start+n {
			self.sampleIndexInSttsEntry = index - start
			self.dts += int64(index-start) * int64(entry.Duration)
			found = true
			break
		}
		start += n
		self.dts += int64(n) * int64(entry.Duration)
		self.sttsEntryIndex++
	}
	if !found {
		err = fmt.Errorf("mp4: stream[%d]: cannot locate sample index in stts entry", self.idx)
		return
	}

	if self.sample.CompositionOffset != nil && len(self.sample.CompositionOffset.Entries) > 0 {
		start = 0
		found = false
		self.cttsEntryIndex = 0
		for self.cttsEntryIndex < len(self.sample.CompositionOffset.Entries) {
			n := int(self.sample.CompositionOffset.Entries[self.cttsEntryIndex].Count)
			if index >= start && index < start+n {
				self.sampleIndexInCttsEntry = index - start
				found = true
				break
			}
			start += n
			self.cttsEntryIndex++
		}
		if !found {
			err = fmt.Errorf("mp4: stream[%d]: cannot locate sample index in ctts entry", self.idx)
			return
		}
	}

	if self.sample.SyncSample != nil {
		self.syncSampleIndex = 0
		for self.syncSampleIndex < len(self.sample.SyncSample.Entries)-1 {
			if self.sample.SyncSample.Entries[self.syncSampleIndex+1]-1 > uint32(index) {
				break
			}
			self.syncSampleIndex++
		}
	}

	if false {
		fmt.Printf("mp4: stream[%d]: setSampleIndex chunkGroupIndex=%d chunkIndex=%d sampleOffsetInChunk=%d\n",
			self.idx, self.chunkGroupIndex, self.chunkIndex, self.sampleOffsetInChunk)
	}

	self.sampleIndex = index
	return
}

func (self *Stream) isSampleValid() bool {
	if self.chunkIndex >= len(self.sample.ChunkOffset.Entries) {
		return false
	}
	if self.chunkGroupIndex >= len(self.sample.SampleToChunk.Entries) {
		return false
	}
	if self.sttsEntryIndex >= len(self.sample.TimeToSample.Entries) {
		return false
	}
	if self.sample.CompositionOffset != nil && len(self.sample.CompositionOffset.Entries) > 0 {
		if self.cttsEntryIndex >= len(self.sample.CompositionOffset.Entries) {
			return false
		}
	}
	if self.sample.SyncSample != nil {
		if self.syncSampleIndex >= len(self.sample.SyncSample.Entries) {
			return false
		}
	}
	if self.sample.SampleSize.SampleSize != 0 {
		if self.sampleIndex >= len(self.sample.SampleSize.Entries) {
			return false
		}
	}
	return true
}

func (self *Stream) incSampleIndex() (duration int64) {
	if false {
		fmt.Printf("incSampleIndex sampleIndex=%d sampleOffsetInChunk=%d sampleIndexInChunk=%d chunkGroupIndex=%d chunkIndex=%d\n",
			self.sampleIndex, self.sampleOffsetInChunk, self.sampleIndexInChunk, self.chunkGroupIndex, self.chunkIndex)
	}

	self.sampleIndexInChunk++
	if uint32(self.sampleIndexInChunk) == self.sample.SampleToChunk.Entries[self.chunkGroupIndex].SamplesPerChunk {
		self.chunkIndex++
		self.sampleIndexInChunk = 0
		self.sampleOffsetInChunk = int64(0)
	} else {
		if self.sample.SampleSize.SampleSize != 0 {
			self.sampleOffsetInChunk += int64(self.sample.SampleSize.SampleSize)
		} else {
			self.sampleOffsetInChunk += int64(self.sample.SampleSize.Entries[self.sampleIndex])
		}
	}

	if self.chunkGroupIndex+1 < len(self.sample.SampleToChunk.Entries) &&
		uint32(self.chunkIndex+1) == self.sample.SampleToChunk.Entries[self.chunkGroupIndex+1].FirstChunk {
		self.chunkGroupIndex++
	}

	sttsEntry := self.sample.TimeToSample.Entries[self.sttsEntryIndex]
	duration = int64(sttsEntry.Duration)
	self.sampleIndexInSttsEntry++
	self.dts += duration
	if uint32(self.sampleIndexInSttsEntry) == sttsEntry.Count {
		self.sampleIndexInSttsEntry = 0
		self.sttsEntryIndex++
	}

	if self.sample.CompositionOffset != nil && len(self.sample.CompositionOffset.Entries) > 0 {
		self.sampleIndexInCttsEntry++
		if uint32(self.sampleIndexInCttsEntry) == self.sample.CompositionOffset.Entries[self.cttsEntryIndex].Count {
			self.sampleIndexInCttsEntry = 0
			self.cttsEntryIndex++
		}
	}

	if self.sample.SyncSample != nil {
		entries := self.sample.SyncSample.Entries
		if self.syncSampleIndex+1 < len(entries) && entries[self.syncSampleIndex+1]-1 == uint32(self.sampleIndex+1) {
			self.syncSampleIndex++
		}
	}

	self.sampleIndex++
	return
}

func (self *Stream) sampleCount() int {
	if self.sample.SampleSize.SampleSize == 0 {
		chunkGroupIndex := 0
		count := 0
		for chunkIndex := range self.sample.ChunkOffset.Entries {
			n := int(self.sample.SampleToChunk.Entries[chunkGroupIndex].SamplesPerChunk)
			count += n
			if chunkGroupIndex+1 < len(self.sample.SampleToChunk.Entries) &&
				uint32(chunkIndex+1) == self.sample.SampleToChunk.Entries[chunkGroupIndex+1].FirstChunk {
				chunkGroupIndex++
			}
		}
		return count
	} else {
		return len(self.sample.SampleSize.Entries)
	}
}

func (self *Demuxer) ReadPacket() (pkt av.Packet, err error) {
	if err = self.probe(); err != nil {
		return
	}
	if len(self.streams) == 0 {
		err = errors.New("mp4: no streams available while trying to read a packet")
		return
	}

	var chosen *Stream
	var chosenidx int
	for i, stream := range self.streams {
		if chosen == nil || stream.tsToTime(stream.dts) < chosen.tsToTime(chosen.dts) {
			chosen = stream
			chosenidx = i
		}
	}
	if false {
		fmt.Printf("ReadPacket: chosen index=%v time=%v\n", chosen.idx, chosen.tsToTime(chosen.dts))
	}
	tm := chosen.tsToTime(chosen.dts)
	if pkt, err = chosen.readPacket(); err != nil {
		return
	}
	pkt.Time = tm
	pkt.Idx = int8(chosenidx)
	return
}

func (self *Demuxer) CurrentTime() (tm time.Duration) {
	if len(self.streams) > 0 {
		stream := self.streams[0]
		tm = stream.tsToTime(stream.dts)
	}
	return
}

func (self *Demuxer) SeekToTime(tm time.Duration) (err error) {
	for _, stream := range self.streams {
		if stream.Type().IsVideo() {
			if err = stream.seekToTime(tm); err != nil {
				return
			}
			tm = stream.tsToTime(stream.dts)
			break
		}
	}

	for _, stream := range self.streams {
		if !stream.Type().IsVideo() {
			if err = stream.seekToTime(tm); err != nil {
				return
			}
		}
	}

	return
}

func (self *Stream) readPacket() (pkt av.Packet, err error) {
	if !self.isSampleValid() {
		err = io.EOF
		return
	}
	//fmt.Println("readPacket", self.sampleIndex)

	chunkOffset := self.sample.ChunkOffset.Entries[self.chunkIndex]
	sampleSize := uint32(0)
	if self.sample.SampleSize.SampleSize != 0 {
		sampleSize = self.sample.SampleSize.SampleSize
	} else {
		sampleSize = self.sample.SampleSize.Entries[self.sampleIndex]
	}

	sampleOffset := int64(chunkOffset) + self.sampleOffsetInChunk
	pkt.Data = make([]byte, sampleSize)
	if err = self.demuxer.readat(sampleOffset, pkt.Data); err != nil {
		return
	}

	if self.sample.SyncSample != nil {
		if self.sample.SyncSample.Entries[self.syncSampleIndex]-1 == uint32(self.sampleIndex) {
			pkt.IsKeyFrame = true
		}
	}

	//println("pts/dts", self.ptsEntryIndex, self.dtsEntryIndex)
	if self.sample.CompositionOffset != nil && len(self.sample.CompositionOffset.Entries) > 0 {
		cts := int64(self.sample.CompositionOffset.Entries[self.cttsEntryIndex].Offset)
		pkt.CompositionTime = self.tsToTime(cts)
	}

	self.incSampleIndex()

	return
}

func (self *Stream) seekToTime(tm time.Duration) (err error) {
	index := self.timeToSampleIndex(tm)
	if err = self.setSampleIndex(index); err != nil {
		return
	}
	if false {
		fmt.Printf("stream[%d]: seekToTime index=%v time=%v cur=%v\n", self.idx, index, tm, self.tsToTime(self.dts))
	}
	return
}

func (self *Stream) timeToSampleIndex(tm time.Duration) int {
	targetTs := self.timeToTs(tm)
	targetIndex := 0

	startTs := int64(0)
	endTs := int64(0)
	startIndex := 0
	endIndex := 0
	found := false
	for _, entry := range self.sample.TimeToSample.Entries {
		endTs = startTs + int64(entry.Count*entry.Duration)
		endIndex = startIndex + int(entry.Count)
		if targetTs >= startTs && targetTs < endTs {
			targetIndex = startIndex + int((targetTs-startTs)/int64(entry.Duration))
			found = true
		}
		startTs = endTs
		startIndex = endIndex
	}
	if !found {
		if targetTs < 0 {
			targetIndex = 0
		} else {
			targetIndex = endIndex - 1
		}
	}

	if self.sample.SyncSample != nil {
		entries := self.sample.SyncSample.Entries
		for i := len(entries) - 1; i >= 0; i-- {
			if entries[i]-1 < uint32(targetIndex) {
				targetIndex = int(entries[i] - 1)
				break
			}
		}
	}

	return targetIndex
}


================================================
FILE: format/mp4/handler.go
================================================
package mp4

import (
	"io"
	"github.com/nareix/joy4/av"
	"github.com/nareix/joy4/av/avutil"
)

var CodecTypes = []av.CodecType{av.H264, av.AAC}

func Handler(h *avutil.RegisterHandler) {
	h.Ext = ".mp4"

	h.Probe = func(b []byte) bool {
		switch string(b[4:8]) {
		case "moov","ftyp","free","mdat","moof":
			return true
		}
		return false
	}

	h.ReaderDemuxer = func(r io.Reader) av.Demuxer {
		return NewDemuxer(r.(io.ReadSeeker))
	}

	h.WriterMuxer = func(w io.Writer) av.Muxer {
		return NewMuxer(w.(io.WriteSeeker))
	}

	h.CodecTypes = CodecTypes
}



================================================
FILE: format/mp4/mp4io/atoms.go
================================================
package mp4io

import "github.com/nareix/joy4/utils/bits/pio"
import "time"

const MOOF = Tag(0x6d6f6f66)

func (self MovieFrag) Tag() Tag {
	return MOOF
}

const HDLR = Tag(0x68646c72)

func (self HandlerRefer) Tag() Tag {
	return HDLR
}

const AVC1 = Tag(0x61766331)

func (self AVC1Desc) Tag() Tag {
	return AVC1
}

const URL  = Tag(0x75726c20)

func (self DataReferUrl) Tag() Tag {
	return URL
}

const TREX = Tag(0x74726578)

func (self TrackExtend) Tag() Tag {
	return TREX
}

const ESDS = Tag(0x65736473)

func (self ElemStreamDesc) Tag() Tag {
	return ESDS
}

const MDHD = Tag(0x6d646864)

func (self MediaHeader) Tag() Tag {
	return MDHD
}

const STTS = Tag(0x73747473)

func (self TimeToSample) Tag() Tag {
	return STTS
}

const STSS = Tag(0x73747373)

func (self SyncSample) Tag() Tag {
	return STSS
}

const MFHD = Tag(0x6d666864)

func (self MovieFragHeader) Tag() Tag {
	return MFHD
}

const MVHD = Tag(0x6d766864)

func (self MovieHeader) Tag() Tag {
	return MVHD
}

const MINF = Tag(0x6d696e66)

func (self MediaInfo) Tag() Tag {
	return MINF
}

const MOOV = Tag(0x6d6f6f76)

func (self Movie) Tag() Tag {
	return MOOV
}

const MVEX = Tag(0x6d766578)

func (self MovieExtend) Tag() Tag {
	return MVEX
}

const STSD = Tag(0x73747364)

func (self SampleDesc) Tag() Tag {
	return STSD
}

const MP4A = Tag(0x6d703461)

func (self MP4ADesc) Tag() Tag {
	return MP4A
}

const CTTS = Tag(0x63747473)

func (self CompositionOffset) Tag() Tag {
	return CTTS
}

const STCO = Tag(0x7374636f)

func (self ChunkOffset) Tag() Tag {
	return STCO
}

const TRUN = Tag(0x7472756e)

func (self TrackFragRun) Tag() Tag {
	return TRUN
}

const TRAK = Tag(0x7472616b)

func (self Track) Tag() Tag {
	return TRAK
}

const MDIA = Tag(0x6d646961)

func (self Media) Tag() Tag {
	return MDIA
}

const STSC = Tag(0x73747363)

func (self SampleToChunk) Tag() Tag {
	return STSC
}

const VMHD = Tag(0x766d6864)

func (self VideoMediaInfo) Tag() Tag {
	return VMHD
}

const STBL = Tag(0x7374626c)

func (self SampleTable) Tag() Tag {
	return STBL
}

const AVCC = Tag(0x61766343)

func (self AVC1Conf) Tag() Tag {
	return AVCC
}

const TFDT = Tag(0x74666474)

func (self TrackFragDecodeTime) Tag() Tag {
	return TFDT
}

const DINF = Tag(0x64696e66)

func (self DataInfo) Tag() Tag {
	return DINF
}

const DREF = Tag(0x64726566)

func (self DataRefer) Tag() Tag {
	return DREF
}

const TRAF = Tag(0x74726166)

func (self TrackFrag) Tag() Tag {
	return TRAF
}

const STSZ = Tag(0x7374737a)

func (self SampleSize) Tag() Tag {
	return STSZ
}

const TFHD = Tag(0x74666864)

func (self TrackFragHeader) Tag() Tag {
	return TFHD
}

const TKHD = Tag(0x746b6864)

func (self TrackHeader) Tag() Tag {
	return TKHD
}

const SMHD = Tag(0x736d6864)

func (self SoundMediaInfo) Tag() Tag {
	return SMHD
}

const MDAT = Tag(0x6d646174)

type Movie struct {
	Header		*MovieHeader
	MovieExtend	*MovieExtend
	Tracks		[]*Track
	Unknowns	[]Atom
	AtomPos
}

func (self Movie) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(MOOV))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self Movie) marshal(b []byte) (n int) {
	if self.Header != nil {
		n += self.Header.Marshal(b[n:])
	}
	if self.MovieExtend != nil {
		n += self.MovieExtend.Marshal(b[n:])
	}
	for _, atom := range self.Tracks {
		n += atom.Marshal(b[n:])
	}
	for _, atom := range self.Unknowns {
		n += atom.Marshal(b[n:])
	}
	return
}
func (self Movie) Len() (n int) {
	n += 8
	if self.Header != nil {
		n += self.Header.Len()
	}
	if self.MovieExtend != nil {
		n += self.MovieExtend.Len()
	}
	for _, atom := range self.Tracks {
		n += atom.Len()
	}
	for _, atom := range self.Unknowns {
		n += atom.Len()
	}
	return
}
func (self *Movie) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	for n+8 < len(b) {
		tag := Tag(pio.U32BE(b[n+4:]))
		size := int(pio.U32BE(b[n:]))
		if len(b) < n+size {
			err = parseErr("TagSizeInvalid", n+offset, err)
			return
		}
		switch tag {
		case MVHD:
			{
				atom := &MovieHeader{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("mvhd", n+offset, err)
					return
				}
				self.Header = atom
			}
		case MVEX:
			{
				atom := &MovieExtend{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("mvex", n+offset, err)
					return
				}
				self.MovieExtend = atom
			}
		case TRAK:
			{
				atom := &Track{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("trak", n+offset, err)
					return
				}
				self.Tracks = append(self.Tracks, atom)
			}
		default:
			{
				atom := &Dummy{Tag_: tag, Data: b[n:n+size]}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("", n+offset, err)
					return
				}
				self.Unknowns = append(self.Unknowns, atom)
			}
		}
		n += size
	}
	return
}
func (self Movie) Children() (r []Atom) {
	if self.Header != nil {
		r = append(r, self.Header)
	}
	if self.MovieExtend != nil {
		r = append(r, self.MovieExtend)
	}
	for _, atom := range self.Tracks {
		r = append(r, atom)
	}
	r = append(r, self.Unknowns...)
	return
}

type MovieHeader struct {
	Version			uint8
	Flags			uint32
	CreateTime		time.Time
	ModifyTime		time.Time
	TimeScale		int32
	Duration		int32
	PreferredRate		float64
	PreferredVolume		float64
	Matrix			[9]int32
	PreviewTime		time.Time
	PreviewDuration		time.Time
	PosterTime		time.Time
	SelectionTime		time.Time
	SelectionDuration	time.Time
	CurrentTime		time.Time
	NextTrackId		int32
	AtomPos
}

func (self MovieHeader) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(MVHD))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self MovieHeader) marshal(b []byte) (n int) {
	pio.PutU8(b[n:], self.Version)
	n += 1
	pio.PutU24BE(b[n:], self.Flags)
	n += 3
	PutTime32(b[n:], self.CreateTime)
	n += 4
	PutTime32(b[n:], self.ModifyTime)
	n += 4
	pio.PutI32BE(b[n:], self.TimeScale)
	n += 4
	pio.PutI32BE(b[n:], self.Duration)
	n += 4
	PutFixed32(b[n:], self.PreferredRate)
	n += 4
	PutFixed16(b[n:], self.PreferredVolume)
	n += 2
	n += 10
	for _, entry := range self.Matrix {
		pio.PutI32BE(b[n:], entry)
		n += 4
	}
	PutTime32(b[n:], self.PreviewTime)
	n += 4
	PutTime32(b[n:], self.PreviewDuration)
	n += 4
	PutTime32(b[n:], self.PosterTime)
	n += 4
	PutTime32(b[n:], self.SelectionTime)
	n += 4
	PutTime32(b[n:], self.SelectionDuration)
	n += 4
	PutTime32(b[n:], self.CurrentTime)
	n += 4
	pio.PutI32BE(b[n:], self.NextTrackId)
	n += 4
	return
}
func (self MovieHeader) Len() (n int) {
	n += 8
	n += 1
	n += 3
	n += 4
	n += 4
	n += 4
	n += 4
	n += 4
	n += 2
	n += 10
	n += 4*len(self.Matrix[:])
	n += 4
	n += 4
	n += 4
	n += 4
	n += 4
	n += 4
	n += 4
	return
}
func (self *MovieHeader) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	if len(b) < n+1 {
		err = parseErr("Version", n+offset, err)
		return
	}
	self.Version = pio.U8(b[n:])
	n += 1
	if len(b) < n+3 {
		err = parseErr("Flags", n+offset, err)
		return
	}
	self.Flags = pio.U24BE(b[n:])
	n += 3
	if len(b) < n+4 {
		err = parseErr("CreateTime", n+offset, err)
		return
	}
	self.CreateTime = GetTime32(b[n:])
	n += 4
	if len(b) < n+4 {
		err = parseErr("ModifyTime", n+offset, err)
		return
	}
	self.ModifyTime = GetTime32(b[n:])
	n += 4
	if len(b) < n+4 {
		err = parseErr("TimeScale", n+offset, err)
		return
	}
	self.TimeScale = pio.I32BE(b[n:])
	n += 4
	if len(b) < n+4 {
		err = parseErr("Duration", n+offset, err)
		return
	}
	self.Duration = pio.I32BE(b[n:])
	n += 4
	if len(b) < n+4 {
		err = parseErr("PreferredRate", n+offset, err)
		return
	}
	self.PreferredRate = GetFixed32(b[n:])
	n += 4
	if len(b) < n+2 {
		err = parseErr("PreferredVolume", n+offset, err)
		return
	}
	self.PreferredVolume = GetFixed16(b[n:])
	n += 2
	n += 10
	if len(b) < n+4*len(self.Matrix) {
		err = parseErr("Matrix", n+offset, err)
		return
	}
	for i := range self.Matrix {
		self.Matrix[i] = pio.I32BE(b[n:])
		n += 4
	}
	if len(b) < n+4 {
		err = parseErr("PreviewTime", n+offset, err)
		return
	}
	self.PreviewTime = GetTime32(b[n:])
	n += 4
	if len(b) < n+4 {
		err = parseErr("PreviewDuration", n+offset, err)
		return
	}
	self.PreviewDuration = GetTime32(b[n:])
	n += 4
	if len(b) < n+4 {
		err = parseErr("PosterTime", n+offset, err)
		return
	}
	self.PosterTime = GetTime32(b[n:])
	n += 4
	if len(b) < n+4 {
		err = parseErr("SelectionTime", n+offset, err)
		return
	}
	self.SelectionTime = GetTime32(b[n:])
	n += 4
	if len(b) < n+4 {
		err = parseErr("SelectionDuration", n+offset, err)
		return
	}
	self.SelectionDuration = GetTime32(b[n:])
	n += 4
	if len(b) < n+4 {
		err = parseErr("CurrentTime", n+offset, err)
		return
	}
	self.CurrentTime = GetTime32(b[n:])
	n += 4
	if len(b) < n+4 {
		err = parseErr("NextTrackId", n+offset, err)
		return
	}
	self.NextTrackId = pio.I32BE(b[n:])
	n += 4
	return
}
func (self MovieHeader) Children() (r []Atom) {
	return
}

type Track struct {
	Header		*TrackHeader
	Media		*Media
	Unknowns	[]Atom
	AtomPos
}

func (self Track) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(TRAK))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self Track) marshal(b []byte) (n int) {
	if self.Header != nil {
		n += self.Header.Marshal(b[n:])
	}
	if self.Media != nil {
		n += self.Media.Marshal(b[n:])
	}
	for _, atom := range self.Unknowns {
		n += atom.Marshal(b[n:])
	}
	return
}
func (self Track) Len() (n int) {
	n += 8
	if self.Header != nil {
		n += self.Header.Len()
	}
	if self.Media != nil {
		n += self.Media.Len()
	}
	for _, atom := range self.Unknowns {
		n += atom.Len()
	}
	return
}
func (self *Track) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	for n+8 < len(b) {
		tag := Tag(pio.U32BE(b[n+4:]))
		size := int(pio.U32BE(b[n:]))
		if len(b) < n+size {
			err = parseErr("TagSizeInvalid", n+offset, err)
			return
		}
		switch tag {
		case TKHD:
			{
				atom := &TrackHeader{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("tkhd", n+offset, err)
					return
				}
				self.Header = atom
			}
		case MDIA:
			{
				atom := &Media{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("mdia", n+offset, err)
					return
				}
				self.Media = atom
			}
		default:
			{
				atom := &Dummy{Tag_: tag, Data: b[n:n+size]}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("", n+offset, err)
					return
				}
				self.Unknowns = append(self.Unknowns, atom)
			}
		}
		n += size
	}
	return
}
func (self Track) Children() (r []Atom) {
	if self.Header != nil {
		r = append(r, self.Header)
	}
	if self.Media != nil {
		r = append(r, self.Media)
	}
	r = append(r, self.Unknowns...)
	return
}

type TrackHeader struct {
	Version		uint8
	Flags		uint32
	CreateTime	time.Time
	ModifyTime	time.Time
	TrackId		int32
	Duration	int32
	Layer		int16
	AlternateGroup	int16
	Volume		float64
	Matrix		[9]int32
	TrackWidth	float64
	TrackHeight	float64
	AtomPos
}

func (self TrackHeader) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(TKHD))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self TrackHeader) marshal(b []byte) (n int) {
	pio.PutU8(b[n:], self.Version)
	n += 1
	pio.PutU24BE(b[n:], self.Flags)
	n += 3
	PutTime32(b[n:], self.CreateTime)
	n += 4
	PutTime32(b[n:], self.ModifyTime)
	n += 4
	pio.PutI32BE(b[n:], self.TrackId)
	n += 4
	n += 4
	pio.PutI32BE(b[n:], self.Duration)
	n += 4
	n += 8
	pio.PutI16BE(b[n:], self.Layer)
	n += 2
	pio.PutI16BE(b[n:], self.AlternateGroup)
	n += 2
	PutFixed16(b[n:], self.Volume)
	n += 2
	n += 2
	for _, entry := range self.Matrix {
		pio.PutI32BE(b[n:], entry)
		n += 4
	}
	PutFixed32(b[n:], self.TrackWidth)
	n += 4
	PutFixed32(b[n:], self.TrackHeight)
	n += 4
	return
}
func (self TrackHeader) Len() (n int) {
	n += 8
	n += 1
	n += 3
	n += 4
	n += 4
	n += 4
	n += 4
	n += 4
	n += 8
	n += 2
	n += 2
	n += 2
	n += 2
	n += 4*len(self.Matrix[:])
	n += 4
	n += 4
	return
}
func (self *TrackHeader) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	if len(b) < n+1 {
		err = parseErr("Version", n+offset, err)
		return
	}
	self.Version = pio.U8(b[n:])
	n += 1
	if len(b) < n+3 {
		err = parseErr("Flags", n+offset, err)
		return
	}
	self.Flags = pio.U24BE(b[n:])
	n += 3
	if len(b) < n+4 {
		err = parseErr("CreateTime", n+offset, err)
		return
	}
	self.CreateTime = GetTime32(b[n:])
	n += 4
	if len(b) < n+4 {
		err = parseErr("ModifyTime", n+offset, err)
		return
	}
	self.ModifyTime = GetTime32(b[n:])
	n += 4
	if len(b) < n+4 {
		err = parseErr("TrackId", n+offset, err)
		return
	}
	self.TrackId = pio.I32BE(b[n:])
	n += 4
	n += 4
	if len(b) < n+4 {
		err = parseErr("Duration", n+offset, err)
		return
	}
	self.Duration = pio.I32BE(b[n:])
	n += 4
	n += 8
	if len(b) < n+2 {
		err = parseErr("Layer", n+offset, err)
		return
	}
	self.Layer = pio.I16BE(b[n:])
	n += 2
	if len(b) < n+2 {
		err = parseErr("AlternateGroup", n+offset, err)
		return
	}
	self.AlternateGroup = pio.I16BE(b[n:])
	n += 2
	if len(b) < n+2 {
		err = parseErr("Volume", n+offset, err)
		return
	}
	self.Volume = GetFixed16(b[n:])
	n += 2
	n += 2
	if len(b) < n+4*len(self.Matrix) {
		err = parseErr("Matrix", n+offset, err)
		return
	}
	for i := range self.Matrix {
		self.Matrix[i] = pio.I32BE(b[n:])
		n += 4
	}
	if len(b) < n+4 {
		err = parseErr("TrackWidth", n+offset, err)
		return
	}
	self.TrackWidth = GetFixed32(b[n:])
	n += 4
	if len(b) < n+4 {
		err = parseErr("TrackHeight", n+offset, err)
		return
	}
	self.TrackHeight = GetFixed32(b[n:])
	n += 4
	return
}
func (self TrackHeader) Children() (r []Atom) {
	return
}

type HandlerRefer struct {
	Version	uint8
	Flags	uint32
	Type	[4]byte
	SubType	[4]byte
	Name	[]byte
	AtomPos
}

func (self HandlerRefer) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(HDLR))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self HandlerRefer) marshal(b []byte) (n int) {
	pio.PutU8(b[n:], self.Version)
	n += 1
	pio.PutU24BE(b[n:], self.Flags)
	n += 3
	copy(b[n:], self.Type[:])
	n += len(self.Type[:])
	copy(b[n:], self.SubType[:])
	n += len(self.SubType[:])
	copy(b[n:], self.Name[:])
	n += len(self.Name[:])
	return
}
func (self HandlerRefer) Len() (n int) {
	n += 8
	n += 1
	n += 3
	n += len(self.Type[:])
	n += len(self.SubType[:])
	n += len(self.Name[:])
	return
}
func (self *HandlerRefer) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	if len(b) < n+1 {
		err = parseErr("Version", n+offset, err)
		return
	}
	self.Version = pio.U8(b[n:])
	n += 1
	if len(b) < n+3 {
		err = parseErr("Flags", n+offset, err)
		return
	}
	self.Flags = pio.U24BE(b[n:])
	n += 3
	if len(b) < n+len(self.Type) {
		err = parseErr("Type", n+offset, err)
		return
	}
	copy(self.Type[:], b[n:])
	n += len(self.Type)
	if len(b) < n+len(self.SubType) {
		err = parseErr("SubType", n+offset, err)
		return
	}
	copy(self.SubType[:], b[n:])
	n += len(self.SubType)
	self.Name = b[n:]
	n += len(b[n:])
	return
}
func (self HandlerRefer) Children() (r []Atom) {
	return
}

type Media struct {
	Header		*MediaHeader
	Handler		*HandlerRefer
	Info		*MediaInfo
	Unknowns	[]Atom
	AtomPos
}

func (self Media) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(MDIA))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self Media) marshal(b []byte) (n int) {
	if self.Header != nil {
		n += self.Header.Marshal(b[n:])
	}
	if self.Handler != nil {
		n += self.Handler.Marshal(b[n:])
	}
	if self.Info != nil {
		n += self.Info.Marshal(b[n:])
	}
	for _, atom := range self.Unknowns {
		n += atom.Marshal(b[n:])
	}
	return
}
func (self Media) Len() (n int) {
	n += 8
	if self.Header != nil {
		n += self.Header.Len()
	}
	if self.Handler != nil {
		n += self.Handler.Len()
	}
	if self.Info != nil {
		n += self.Info.Len()
	}
	for _, atom := range self.Unknowns {
		n += atom.Len()
	}
	return
}
func (self *Media) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	for n+8 < len(b) {
		tag := Tag(pio.U32BE(b[n+4:]))
		size := int(pio.U32BE(b[n:]))
		if len(b) < n+size {
			err = parseErr("TagSizeInvalid", n+offset, err)
			return
		}
		switch tag {
		case MDHD:
			{
				atom := &MediaHeader{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("mdhd", n+offset, err)
					return
				}
				self.Header = atom
			}
		case HDLR:
			{
				atom := &HandlerRefer{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("hdlr", n+offset, err)
					return
				}
				self.Handler = atom
			}
		case MINF:
			{
				atom := &MediaInfo{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("minf", n+offset, err)
					return
				}
				self.Info = atom
			}
		default:
			{
				atom := &Dummy{Tag_: tag, Data: b[n:n+size]}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("", n+offset, err)
					return
				}
				self.Unknowns = append(self.Unknowns, atom)
			}
		}
		n += size
	}
	return
}
func (self Media) Children() (r []Atom) {
	if self.Header != nil {
		r = append(r, self.Header)
	}
	if self.Handler != nil {
		r = append(r, self.Handler)
	}
	if self.Info != nil {
		r = append(r, self.Info)
	}
	r = append(r, self.Unknowns...)
	return
}

type MediaHeader struct {
	Version		uint8
	Flags		uint32
	CreateTime	time.Time
	ModifyTime	time.Time
	TimeScale	int32
	Duration	int32
	Language	int16
	Quality		int16
	AtomPos
}

func (self MediaHeader) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(MDHD))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self MediaHeader) marshal(b []byte) (n int) {
	pio.PutU8(b[n:], self.Version)
	n += 1
	pio.PutU24BE(b[n:], self.Flags)
	n += 3
	PutTime32(b[n:], self.CreateTime)
	n += 4
	PutTime32(b[n:], self.ModifyTime)
	n += 4
	pio.PutI32BE(b[n:], self.TimeScale)
	n += 4
	pio.PutI32BE(b[n:], self.Duration)
	n += 4
	pio.PutI16BE(b[n:], self.Language)
	n += 2
	pio.PutI16BE(b[n:], self.Quality)
	n += 2
	return
}
func (self MediaHeader) Len() (n int) {
	n += 8
	n += 1
	n += 3
	n += 4
	n += 4
	n += 4
	n += 4
	n += 2
	n += 2
	return
}
func (self *MediaHeader) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	if len(b) < n+1 {
		err = parseErr("Version", n+offset, err)
		return
	}
	self.Version = pio.U8(b[n:])
	n += 1
	if len(b) < n+3 {
		err = parseErr("Flags", n+offset, err)
		return
	}
	self.Flags = pio.U24BE(b[n:])
	n += 3
	if len(b) < n+4 {
		err = parseErr("CreateTime", n+offset, err)
		return
	}
	self.CreateTime = GetTime32(b[n:])
	n += 4
	if len(b) < n+4 {
		err = parseErr("ModifyTime", n+offset, err)
		return
	}
	self.ModifyTime = GetTime32(b[n:])
	n += 4
	if len(b) < n+4 {
		err = parseErr("TimeScale", n+offset, err)
		return
	}
	self.TimeScale = pio.I32BE(b[n:])
	n += 4
	if len(b) < n+4 {
		err = parseErr("Duration", n+offset, err)
		return
	}
	self.Duration = pio.I32BE(b[n:])
	n += 4
	if len(b) < n+2 {
		err = parseErr("Language", n+offset, err)
		return
	}
	self.Language = pio.I16BE(b[n:])
	n += 2
	if len(b) < n+2 {
		err = parseErr("Quality", n+offset, err)
		return
	}
	self.Quality = pio.I16BE(b[n:])
	n += 2
	return
}
func (self MediaHeader) Children() (r []Atom) {
	return
}

type MediaInfo struct {
	Sound		*SoundMediaInfo
	Video		*VideoMediaInfo
	Data		*DataInfo
	Sample		*SampleTable
	Unknowns	[]Atom
	AtomPos
}

func (self MediaInfo) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(MINF))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self MediaInfo) marshal(b []byte) (n int) {
	if self.Sound != nil {
		n += self.Sound.Marshal(b[n:])
	}
	if self.Video != nil {
		n += self.Video.Marshal(b[n:])
	}
	if self.Data != nil {
		n += self.Data.Marshal(b[n:])
	}
	if self.Sample != nil {
		n += self.Sample.Marshal(b[n:])
	}
	for _, atom := range self.Unknowns {
		n += atom.Marshal(b[n:])
	}
	return
}
func (self MediaInfo) Len() (n int) {
	n += 8
	if self.Sound != nil {
		n += self.Sound.Len()
	}
	if self.Video != nil {
		n += self.Video.Len()
	}
	if self.Data != nil {
		n += self.Data.Len()
	}
	if self.Sample != nil {
		n += self.Sample.Len()
	}
	for _, atom := range self.Unknowns {
		n += atom.Len()
	}
	return
}
func (self *MediaInfo) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	for n+8 < len(b) {
		tag := Tag(pio.U32BE(b[n+4:]))
		size := int(pio.U32BE(b[n:]))
		if len(b) < n+size {
			err = parseErr("TagSizeInvalid", n+offset, err)
			return
		}
		switch tag {
		case SMHD:
			{
				atom := &SoundMediaInfo{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("smhd", n+offset, err)
					return
				}
				self.Sound = atom
			}
		case VMHD:
			{
				atom := &VideoMediaInfo{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("vmhd", n+offset, err)
					return
				}
				self.Video = atom
			}
		case DINF:
			{
				atom := &DataInfo{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("dinf", n+offset, err)
					return
				}
				self.Data = atom
			}
		case STBL:
			{
				atom := &SampleTable{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("stbl", n+offset, err)
					return
				}
				self.Sample = atom
			}
		default:
			{
				atom := &Dummy{Tag_: tag, Data: b[n:n+size]}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("", n+offset, err)
					return
				}
				self.Unknowns = append(self.Unknowns, atom)
			}
		}
		n += size
	}
	return
}
func (self MediaInfo) Children() (r []Atom) {
	if self.Sound != nil {
		r = append(r, self.Sound)
	}
	if self.Video != nil {
		r = append(r, self.Video)
	}
	if self.Data != nil {
		r = append(r, self.Data)
	}
	if self.Sample != nil {
		r = append(r, self.Sample)
	}
	r = append(r, self.Unknowns...)
	return
}

type DataInfo struct {
	Refer		*DataRefer
	Unknowns	[]Atom
	AtomPos
}

func (self DataInfo) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(DINF))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self DataInfo) marshal(b []byte) (n int) {
	if self.Refer != nil {
		n += self.Refer.Marshal(b[n:])
	}
	for _, atom := range self.Unknowns {
		n += atom.Marshal(b[n:])
	}
	return
}
func (self DataInfo) Len() (n int) {
	n += 8
	if self.Refer != nil {
		n += self.Refer.Len()
	}
	for _, atom := range self.Unknowns {
		n += atom.Len()
	}
	return
}
func (self *DataInfo) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	for n+8 < len(b) {
		tag := Tag(pio.U32BE(b[n+4:]))
		size := int(pio.U32BE(b[n:]))
		if len(b) < n+size {
			err = parseErr("TagSizeInvalid", n+offset, err)
			return
		}
		switch tag {
		case DREF:
			{
				atom := &DataRefer{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("dref", n+offset, err)
					return
				}
				self.Refer = atom
			}
		default:
			{
				atom := &Dummy{Tag_: tag, Data: b[n:n+size]}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("", n+offset, err)
					return
				}
				self.Unknowns = append(self.Unknowns, atom)
			}
		}
		n += size
	}
	return
}
func (self DataInfo) Children() (r []Atom) {
	if self.Refer != nil {
		r = append(r, self.Refer)
	}
	r = append(r, self.Unknowns...)
	return
}

type DataRefer struct {
	Version	uint8
	Flags	uint32
	Url	*DataReferUrl
	AtomPos
}

func (self DataRefer) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(DREF))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self DataRefer) marshal(b []byte) (n int) {
	pio.PutU8(b[n:], self.Version)
	n += 1
	pio.PutU24BE(b[n:], self.Flags)
	n += 3
	_childrenNR := 0
	if self.Url != nil {
		_childrenNR++
	}
	pio.PutI32BE(b[n:], int32(_childrenNR))
	n += 4
	if self.Url != nil {
		n += self.Url.Marshal(b[n:])
	}
	return
}
func (self DataRefer) Len() (n int) {
	n += 8
	n += 1
	n += 3
	n += 4
	if self.Url != nil {
		n += self.Url.Len()
	}
	return
}
func (self *DataRefer) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	if len(b) < n+1 {
		err = parseErr("Version", n+offset, err)
		return
	}
	self.Version = pio.U8(b[n:])
	n += 1
	if len(b) < n+3 {
		err = parseErr("Flags", n+offset, err)
		return
	}
	self.Flags = pio.U24BE(b[n:])
	n += 3
	n += 4
	for n+8 < len(b) {
		tag := Tag(pio.U32BE(b[n+4:]))
		size := int(pio.U32BE(b[n:]))
		if len(b) < n+size {
			err = parseErr("TagSizeInvalid", n+offset, err)
			return
		}
		switch tag {
		case URL :
			{
				atom := &DataReferUrl{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("url ", n+offset, err)
					return
				}
				self.Url = atom
			}
		}
		n += size
	}
	return
}
func (self DataRefer) Children() (r []Atom) {
	if self.Url != nil {
		r = append(r, self.Url)
	}
	return
}

type DataReferUrl struct {
	Version	uint8
	Flags	uint32
	AtomPos
}

func (self DataReferUrl) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(URL ))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self DataReferUrl) marshal(b []byte) (n int) {
	pio.PutU8(b[n:], self.Version)
	n += 1
	pio.PutU24BE(b[n:], self.Flags)
	n += 3
	return
}
func (self DataReferUrl) Len() (n int) {
	n += 8
	n += 1
	n += 3
	return
}
func (self *DataReferUrl) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	if len(b) < n+1 {
		err = parseErr("Version", n+offset, err)
		return
	}
	self.Version = pio.U8(b[n:])
	n += 1
	if len(b) < n+3 {
		err = parseErr("Flags", n+offset, err)
		return
	}
	self.Flags = pio.U24BE(b[n:])
	n += 3
	return
}
func (self DataReferUrl) Children() (r []Atom) {
	return
}

type SoundMediaInfo struct {
	Version	uint8
	Flags	uint32
	Balance	int16
	AtomPos
}

func (self SoundMediaInfo) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(SMHD))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self SoundMediaInfo) marshal(b []byte) (n int) {
	pio.PutU8(b[n:], self.Version)
	n += 1
	pio.PutU24BE(b[n:], self.Flags)
	n += 3
	pio.PutI16BE(b[n:], self.Balance)
	n += 2
	n += 2
	return
}
func (self SoundMediaInfo) Len() (n int) {
	n += 8
	n += 1
	n += 3
	n += 2
	n += 2
	return
}
func (self *SoundMediaInfo) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	if len(b) < n+1 {
		err = parseErr("Version", n+offset, err)
		return
	}
	self.Version = pio.U8(b[n:])
	n += 1
	if len(b) < n+3 {
		err = parseErr("Flags", n+offset, err)
		return
	}
	self.Flags = pio.U24BE(b[n:])
	n += 3
	if len(b) < n+2 {
		err = parseErr("Balance", n+offset, err)
		return
	}
	self.Balance = pio.I16BE(b[n:])
	n += 2
	n += 2
	return
}
func (self SoundMediaInfo) Children() (r []Atom) {
	return
}

type VideoMediaInfo struct {
	Version		uint8
	Flags		uint32
	GraphicsMode	int16
	Opcolor		[3]int16
	AtomPos
}

func (self VideoMediaInfo) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(VMHD))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self VideoMediaInfo) marshal(b []byte) (n int) {
	pio.PutU8(b[n:], self.Version)
	n += 1
	pio.PutU24BE(b[n:], self.Flags)
	n += 3
	pio.PutI16BE(b[n:], self.GraphicsMode)
	n += 2
	for _, entry := range self.Opcolor {
		pio.PutI16BE(b[n:], entry)
		n += 2
	}
	return
}
func (self VideoMediaInfo) Len() (n int) {
	n += 8
	n += 1
	n += 3
	n += 2
	n += 2*len(self.Opcolor[:])
	return
}
func (self *VideoMediaInfo) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	if len(b) < n+1 {
		err = parseErr("Version", n+offset, err)
		return
	}
	self.Version = pio.U8(b[n:])
	n += 1
	if len(b) < n+3 {
		err = parseErr("Flags", n+offset, err)
		return
	}
	self.Flags = pio.U24BE(b[n:])
	n += 3
	if len(b) < n+2 {
		err = parseErr("GraphicsMode", n+offset, err)
		return
	}
	self.GraphicsMode = pio.I16BE(b[n:])
	n += 2
	if len(b) < n+2*len(self.Opcolor) {
		err = parseErr("Opcolor", n+offset, err)
		return
	}
	for i := range self.Opcolor {
		self.Opcolor[i] = pio.I16BE(b[n:])
		n += 2
	}
	return
}
func (self VideoMediaInfo) Children() (r []Atom) {
	return
}

type SampleTable struct {
	SampleDesc		*SampleDesc
	TimeToSample		*TimeToSample
	CompositionOffset	*CompositionOffset
	SampleToChunk		*SampleToChunk
	SyncSample		*SyncSample
	ChunkOffset		*ChunkOffset
	SampleSize		*SampleSize
	AtomPos
}

func (self SampleTable) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(STBL))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self SampleTable) marshal(b []byte) (n int) {
	if self.SampleDesc != nil {
		n += self.SampleDesc.Marshal(b[n:])
	}
	if self.TimeToSample != nil {
		n += self.TimeToSample.Marshal(b[n:])
	}
	if self.CompositionOffset != nil {
		n += self.CompositionOffset.Marshal(b[n:])
	}
	if self.SampleToChunk != nil {
		n += self.SampleToChunk.Marshal(b[n:])
	}
	if self.SyncSample != nil {
		n += self.SyncSample.Marshal(b[n:])
	}
	if self.ChunkOffset != nil {
		n += self.ChunkOffset.Marshal(b[n:])
	}
	if self.SampleSize != nil {
		n += self.SampleSize.Marshal(b[n:])
	}
	return
}
func (self SampleTable) Len() (n int) {
	n += 8
	if self.SampleDesc != nil {
		n += self.SampleDesc.Len()
	}
	if self.TimeToSample != nil {
		n += self.TimeToSample.Len()
	}
	if self.CompositionOffset != nil {
		n += self.CompositionOffset.Len()
	}
	if self.SampleToChunk != nil {
		n += self.SampleToChunk.Len()
	}
	if self.SyncSample != nil {
		n += self.SyncSample.Len()
	}
	if self.ChunkOffset != nil {
		n += self.ChunkOffset.Len()
	}
	if self.SampleSize != nil {
		n += self.SampleSize.Len()
	}
	return
}
func (self *SampleTable) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	for n+8 < len(b) {
		tag := Tag(pio.U32BE(b[n+4:]))
		size := int(pio.U32BE(b[n:]))
		if len(b) < n+size {
			err = parseErr("TagSizeInvalid", n+offset, err)
			return
		}
		switch tag {
		case STSD:
			{
				atom := &SampleDesc{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("stsd", n+offset, err)
					return
				}
				self.SampleDesc = atom
			}
		case STTS:
			{
				atom := &TimeToSample{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("stts", n+offset, err)
					return
				}
				self.TimeToSample = atom
			}
		case CTTS:
			{
				atom := &CompositionOffset{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("ctts", n+offset, err)
					return
				}
				self.CompositionOffset = atom
			}
		case STSC:
			{
				atom := &SampleToChunk{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("stsc", n+offset, err)
					return
				}
				self.SampleToChunk = atom
			}
		case STSS:
			{
				atom := &SyncSample{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("stss", n+offset, err)
					return
				}
				self.SyncSample = atom
			}
		case STCO:
			{
				atom := &ChunkOffset{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("stco", n+offset, err)
					return
				}
				self.ChunkOffset = atom
			}
		case STSZ:
			{
				atom := &SampleSize{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("stsz", n+offset, err)
					return
				}
				self.SampleSize = atom
			}
		}
		n += size
	}
	return
}
func (self SampleTable) Children() (r []Atom) {
	if self.SampleDesc != nil {
		r = append(r, self.SampleDesc)
	}
	if self.TimeToSample != nil {
		r = append(r, self.TimeToSample)
	}
	if self.CompositionOffset != nil {
		r = append(r, self.CompositionOffset)
	}
	if self.SampleToChunk != nil {
		r = append(r, self.SampleToChunk)
	}
	if self.SyncSample != nil {
		r = append(r, self.SyncSample)
	}
	if self.ChunkOffset != nil {
		r = append(r, self.ChunkOffset)
	}
	if self.SampleSize != nil {
		r = append(r, self.SampleSize)
	}
	return
}

type SampleDesc struct {
	Version		uint8
	AVC1Desc	*AVC1Desc
	MP4ADesc	*MP4ADesc
	Unknowns	[]Atom
	AtomPos
}

func (self SampleDesc) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(STSD))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self SampleDesc) marshal(b []byte) (n int) {
	pio.PutU8(b[n:], self.Version)
	n += 1
	n += 3
	_childrenNR := 0
	if self.AVC1Desc != nil {
		_childrenNR++
	}
	if self.MP4ADesc != nil {
		_childrenNR++
	}
	_childrenNR += len(self.Unknowns)
	pio.PutI32BE(b[n:], int32(_childrenNR))
	n += 4
	if self.AVC1Desc != nil {
		n += self.AVC1Desc.Marshal(b[n:])
	}
	if self.MP4ADesc != nil {
		n += self.MP4ADesc.Marshal(b[n:])
	}
	for _, atom := range self.Unknowns {
		n += atom.Marshal(b[n:])
	}
	return
}
func (self SampleDesc) Len() (n int) {
	n += 8
	n += 1
	n += 3
	n += 4
	if self.AVC1Desc != nil {
		n += self.AVC1Desc.Len()
	}
	if self.MP4ADesc != nil {
		n += self.MP4ADesc.Len()
	}
	for _, atom := range self.Unknowns {
		n += atom.Len()
	}
	return
}
func (self *SampleDesc) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	if len(b) < n+1 {
		err = parseErr("Version", n+offset, err)
		return
	}
	self.Version = pio.U8(b[n:])
	n += 1
	n += 3
	n += 4
	for n+8 < len(b) {
		tag := Tag(pio.U32BE(b[n+4:]))
		size := int(pio.U32BE(b[n:]))
		if len(b) < n+size {
			err = parseErr("TagSizeInvalid", n+offset, err)
			return
		}
		switch tag {
		case AVC1:
			{
				atom := &AVC1Desc{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("avc1", n+offset, err)
					return
				}
				self.AVC1Desc = atom
			}
		case MP4A:
			{
				atom := &MP4ADesc{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("mp4a", n+offset, err)
					return
				}
				self.MP4ADesc = atom
			}
		default:
			{
				atom := &Dummy{Tag_: tag, Data: b[n:n+size]}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("", n+offset, err)
					return
				}
				self.Unknowns = append(self.Unknowns, atom)
			}
		}
		n += size
	}
	return
}
func (self SampleDesc) Children() (r []Atom) {
	if self.AVC1Desc != nil {
		r = append(r, self.AVC1Desc)
	}
	if self.MP4ADesc != nil {
		r = append(r, self.MP4ADesc)
	}
	r = append(r, self.Unknowns...)
	return
}

type MP4ADesc struct {
	DataRefIdx		int16
	Version			int16
	RevisionLevel		int16
	Vendor			int32
	NumberOfChannels	int16
	SampleSize		int16
	CompressionId		int16
	SampleRate		float64
	Conf			*ElemStreamDesc
	Unknowns		[]Atom
	AtomPos
}

func (self MP4ADesc) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(MP4A))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self MP4ADesc) marshal(b []byte) (n int) {
	n += 6
	pio.PutI16BE(b[n:], self.DataRefIdx)
	n += 2
	pio.PutI16BE(b[n:], self.Version)
	n += 2
	pio.PutI16BE(b[n:], self.RevisionLevel)
	n += 2
	pio.PutI32BE(b[n:], self.Vendor)
	n += 4
	pio.PutI16BE(b[n:], self.NumberOfChannels)
	n += 2
	pio.PutI16BE(b[n:], self.SampleSize)
	n += 2
	pio.PutI16BE(b[n:], self.CompressionId)
	n += 2
	n += 2
	PutFixed32(b[n:], self.SampleRate)
	n += 4
	if self.Conf != nil {
		n += self.Conf.Marshal(b[n:])
	}
	for _, atom := range self.Unknowns {
		n += atom.Marshal(b[n:])
	}
	return
}
func (self MP4ADesc) Len() (n int) {
	n += 8
	n += 6
	n += 2
	n += 2
	n += 2
	n += 4
	n += 2
	n += 2
	n += 2
	n += 2
	n += 4
	if self.Conf != nil {
		n += self.Conf.Len()
	}
	for _, atom := range self.Unknowns {
		n += atom.Len()
	}
	return
}
func (self *MP4ADesc) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	n += 6
	if len(b) < n+2 {
		err = parseErr("DataRefIdx", n+offset, err)
		return
	}
	self.DataRefIdx = pio.I16BE(b[n:])
	n += 2
	if len(b) < n+2 {
		err = parseErr("Version", n+offset, err)
		return
	}
	self.Version = pio.I16BE(b[n:])
	n += 2
	if len(b) < n+2 {
		err = parseErr("RevisionLevel", n+offset, err)
		return
	}
	self.RevisionLevel = pio.I16BE(b[n:])
	n += 2
	if len(b) < n+4 {
		err = parseErr("Vendor", n+offset, err)
		return
	}
	self.Vendor = pio.I32BE(b[n:])
	n += 4
	if len(b) < n+2 {
		err = parseErr("NumberOfChannels", n+offset, err)
		return
	}
	self.NumberOfChannels = pio.I16BE(b[n:])
	n += 2
	if len(b) < n+2 {
		err = parseErr("SampleSize", n+offset, err)
		return
	}
	self.SampleSize = pio.I16BE(b[n:])
	n += 2
	if len(b) < n+2 {
		err = parseErr("CompressionId", n+offset, err)
		return
	}
	self.CompressionId = pio.I16BE(b[n:])
	n += 2
	n += 2
	if len(b) < n+4 {
		err = parseErr("SampleRate", n+offset, err)
		return
	}
	self.SampleRate = GetFixed32(b[n:])
	n += 4
	for n+8 < len(b) {
		tag := Tag(pio.U32BE(b[n+4:]))
		size := int(pio.U32BE(b[n:]))
		if len(b) < n+size {
			err = parseErr("TagSizeInvalid", n+offset, err)
			return
		}
		switch tag {
		case ESDS:
			{
				atom := &ElemStreamDesc{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("esds", n+offset, err)
					return
				}
				self.Conf = atom
			}
		default:
			{
				atom := &Dummy{Tag_: tag, Data: b[n:n+size]}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("", n+offset, err)
					return
				}
				self.Unknowns = append(self.Unknowns, atom)
			}
		}
		n += size
	}
	return
}
func (self MP4ADesc) Children() (r []Atom) {
	if self.Conf != nil {
		r = append(r, self.Conf)
	}
	r = append(r, self.Unknowns...)
	return
}

type AVC1Desc struct {
	DataRefIdx		int16
	Version			int16
	Revision		int16
	Vendor			int32
	TemporalQuality		int32
	SpatialQuality		int32
	Width			int16
	Height			int16
	HorizontalResolution	float64
	VorizontalResolution	float64
	FrameCount		int16
	CompressorName		[32]byte
	Depth			int16
	ColorTableId		int16
	Conf			*AVC1Conf
	Unknowns		[]Atom
	AtomPos
}

func (self AVC1Desc) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(AVC1))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self AVC1Desc) marshal(b []byte) (n int) {
	n += 6
	pio.PutI16BE(b[n:], self.DataRefIdx)
	n += 2
	pio.PutI16BE(b[n:], self.Version)
	n += 2
	pio.PutI16BE(b[n:], self.Revision)
	n += 2
	pio.PutI32BE(b[n:], self.Vendor)
	n += 4
	pio.PutI32BE(b[n:], self.TemporalQuality)
	n += 4
	pio.PutI32BE(b[n:], self.SpatialQuality)
	n += 4
	pio.PutI16BE(b[n:], self.Width)
	n += 2
	pio.PutI16BE(b[n:], self.Height)
	n += 2
	PutFixed32(b[n:], self.HorizontalResolution)
	n += 4
	PutFixed32(b[n:], self.VorizontalResolution)
	n += 4
	n += 4
	pio.PutI16BE(b[n:], self.FrameCount)
	n += 2
	copy(b[n:], self.CompressorName[:])
	n += len(self.CompressorName[:])
	pio.PutI16BE(b[n:], self.Depth)
	n += 2
	pio.PutI16BE(b[n:], self.ColorTableId)
	n += 2
	if self.Conf != nil {
		n += self.Conf.Marshal(b[n:])
	}
	for _, atom := range self.Unknowns {
		n += atom.Marshal(b[n:])
	}
	return
}
func (self AVC1Desc) Len() (n int) {
	n += 8
	n += 6
	n += 2
	n += 2
	n += 2
	n += 4
	n += 4
	n += 4
	n += 2
	n += 2
	n += 4
	n += 4
	n += 4
	n += 2
	n += len(self.CompressorName[:])
	n += 2
	n += 2
	if self.Conf != nil {
		n += self.Conf.Len()
	}
	for _, atom := range self.Unknowns {
		n += atom.Len()
	}
	return
}
func (self *AVC1Desc) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	n += 6
	if len(b) < n+2 {
		err = parseErr("DataRefIdx", n+offset, err)
		return
	}
	self.DataRefIdx = pio.I16BE(b[n:])
	n += 2
	if len(b) < n+2 {
		err = parseErr("Version", n+offset, err)
		return
	}
	self.Version = pio.I16BE(b[n:])
	n += 2
	if len(b) < n+2 {
		err = parseErr("Revision", n+offset, err)
		return
	}
	self.Revision = pio.I16BE(b[n:])
	n += 2
	if len(b) < n+4 {
		err = parseErr("Vendor", n+offset, err)
		return
	}
	self.Vendor = pio.I32BE(b[n:])
	n += 4
	if len(b) < n+4 {
		err = parseErr("TemporalQuality", n+offset, err)
		return
	}
	self.TemporalQuality = pio.I32BE(b[n:])
	n += 4
	if len(b) < n+4 {
		err = parseErr("SpatialQuality", n+offset, err)
		return
	}
	self.SpatialQuality = pio.I32BE(b[n:])
	n += 4
	if len(b) < n+2 {
		err = parseErr("Width", n+offset, err)
		return
	}
	self.Width = pio.I16BE(b[n:])
	n += 2
	if len(b) < n+2 {
		err = parseErr("Height", n+offset, err)
		return
	}
	self.Height = pio.I16BE(b[n:])
	n += 2
	if len(b) < n+4 {
		err = parseErr("HorizontalResolution", n+offset, err)
		return
	}
	self.HorizontalResolution = GetFixed32(b[n:])
	n += 4
	if len(b) < n+4 {
		err = parseErr("VorizontalResolution", n+offset, err)
		return
	}
	self.VorizontalResolution = GetFixed32(b[n:])
	n += 4
	n += 4
	if len(b) < n+2 {
		err = parseErr("FrameCount", n+offset, err)
		return
	}
	self.FrameCount = pio.I16BE(b[n:])
	n += 2
	if len(b) < n+len(self.CompressorName) {
		err = parseErr("CompressorName", n+offset, err)
		return
	}
	copy(self.CompressorName[:], b[n:])
	n += len(self.CompressorName)
	if len(b) < n+2 {
		err = parseErr("Depth", n+offset, err)
		return
	}
	self.Depth = pio.I16BE(b[n:])
	n += 2
	if len(b) < n+2 {
		err = parseErr("ColorTableId", n+offset, err)
		return
	}
	self.ColorTableId = pio.I16BE(b[n:])
	n += 2
	for n+8 < len(b) {
		tag := Tag(pio.U32BE(b[n+4:]))
		size := int(pio.U32BE(b[n:]))
		if len(b) < n+size {
			err = parseErr("TagSizeInvalid", n+offset, err)
			return
		}
		switch tag {
		case AVCC:
			{
				atom := &AVC1Conf{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("avcC", n+offset, err)
					return
				}
				self.Conf = atom
			}
		default:
			{
				atom := &Dummy{Tag_: tag, Data: b[n:n+size]}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("", n+offset, err)
					return
				}
				self.Unknowns = append(self.Unknowns, atom)
			}
		}
		n += size
	}
	return
}
func (self AVC1Desc) Children() (r []Atom) {
	if self.Conf != nil {
		r = append(r, self.Conf)
	}
	r = append(r, self.Unknowns...)
	return
}

type AVC1Conf struct {
	Data	[]byte
	AtomPos
}

func (self AVC1Conf) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(AVCC))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self AVC1Conf) marshal(b []byte) (n int) {
	copy(b[n:], self.Data[:])
	n += len(self.Data[:])
	return
}
func (self AVC1Conf) Len() (n int) {
	n += 8
	n += len(self.Data[:])
	return
}
func (self *AVC1Conf) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	self.Data = b[n:]
	n += len(b[n:])
	return
}
func (self AVC1Conf) Children() (r []Atom) {
	return
}

type TimeToSample struct {
	Version	uint8
	Flags	uint32
	Entries	[]TimeToSampleEntry
	AtomPos
}

func (self TimeToSample) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(STTS))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self TimeToSample) marshal(b []byte) (n int) {
	pio.PutU8(b[n:], self.Version)
	n += 1
	pio.PutU24BE(b[n:], self.Flags)
	n += 3
	pio.PutU32BE(b[n:], uint32(len(self.Entries)))
	n += 4
	for _, entry := range self.Entries {
		PutTimeToSampleEntry(b[n:], entry)
		n += LenTimeToSampleEntry
	}
	return
}
func (self TimeToSample) Len() (n int) {
	n += 8
	n += 1
	n += 3
	n += 4
	n += LenTimeToSampleEntry*len(self.Entries)
	return
}
func (self *TimeToSample) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	if len(b) < n+1 {
		err = parseErr("Version", n+offset, err)
		return
	}
	self.Version = pio.U8(b[n:])
	n += 1
	if len(b) < n+3 {
		err = parseErr("Flags", n+offset, err)
		return
	}
	self.Flags = pio.U24BE(b[n:])
	n += 3
	var _len_Entries uint32
	_len_Entries = pio.U32BE(b[n:])
	n += 4
	self.Entries = make([]TimeToSampleEntry, _len_Entries)
	if len(b) < n+LenTimeToSampleEntry*len(self.Entries) {
		err = parseErr("TimeToSampleEntry", n+offset, err)
		return
	}
	for i := range self.Entries {
		self.Entries[i] = GetTimeToSampleEntry(b[n:])
		n += LenTimeToSampleEntry
	}
	return
}
func (self TimeToSample) Children() (r []Atom) {
	return
}

type TimeToSampleEntry struct {
	Count		uint32
	Duration	uint32
}

func GetTimeToSampleEntry(b []byte) (self TimeToSampleEntry) {
	self.Count = pio.U32BE(b[0:])
	self.Duration = pio.U32BE(b[4:])
	return
}
func PutTimeToSampleEntry(b []byte, self TimeToSampleEntry) {
	pio.PutU32BE(b[0:], self.Count)
	pio.PutU32BE(b[4:], self.Duration)
}

const LenTimeToSampleEntry = 8

type SampleToChunk struct {
	Version	uint8
	Flags	uint32
	Entries	[]SampleToChunkEntry
	AtomPos
}

func (self SampleToChunk) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(STSC))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self SampleToChunk) marshal(b []byte) (n int) {
	pio.PutU8(b[n:], self.Version)
	n += 1
	pio.PutU24BE(b[n:], self.Flags)
	n += 3
	pio.PutU32BE(b[n:], uint32(len(self.Entries)))
	n += 4
	for _, entry := range self.Entries {
		PutSampleToChunkEntry(b[n:], entry)
		n += LenSampleToChunkEntry
	}
	return
}
func (self SampleToChunk) Len() (n int) {
	n += 8
	n += 1
	n += 3
	n += 4
	n += LenSampleToChunkEntry*len(self.Entries)
	return
}
func (self *SampleToChunk) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	if len(b) < n+1 {
		err = parseErr("Version", n+offset, err)
		return
	}
	self.Version = pio.U8(b[n:])
	n += 1
	if len(b) < n+3 {
		err = parseErr("Flags", n+offset, err)
		return
	}
	self.Flags = pio.U24BE(b[n:])
	n += 3
	var _len_Entries uint32
	_len_Entries = pio.U32BE(b[n:])
	n += 4
	self.Entries = make([]SampleToChunkEntry, _len_Entries)
	if len(b) < n+LenSampleToChunkEntry*len(self.Entries) {
		err = parseErr("SampleToChunkEntry", n+offset, err)
		return
	}
	for i := range self.Entries {
		self.Entries[i] = GetSampleToChunkEntry(b[n:])
		n += LenSampleToChunkEntry
	}
	return
}
func (self SampleToChunk) Children() (r []Atom) {
	return
}

type SampleToChunkEntry struct {
	FirstChunk	uint32
	SamplesPerChunk	uint32
	SampleDescId	uint32
}

func GetSampleToChunkEntry(b []byte) (self SampleToChunkEntry) {
	self.FirstChunk = pio.U32BE(b[0:])
	self.SamplesPerChunk = pio.U32BE(b[4:])
	self.SampleDescId = pio.U32BE(b[8:])
	return
}
func PutSampleToChunkEntry(b []byte, self SampleToChunkEntry) {
	pio.PutU32BE(b[0:], self.FirstChunk)
	pio.PutU32BE(b[4:], self.SamplesPerChunk)
	pio.PutU32BE(b[8:], self.SampleDescId)
}

const LenSampleToChunkEntry = 12

type CompositionOffset struct {
	Version	uint8
	Flags	uint32
	Entries	[]CompositionOffsetEntry
	AtomPos
}

func (self CompositionOffset) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(CTTS))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self CompositionOffset) marshal(b []byte) (n int) {
	pio.PutU8(b[n:], self.Version)
	n += 1
	pio.PutU24BE(b[n:], self.Flags)
	n += 3
	pio.PutU32BE(b[n:], uint32(len(self.Entries)))
	n += 4
	for _, entry := range self.Entries {
		PutCompositionOffsetEntry(b[n:], entry)
		n += LenCompositionOffsetEntry
	}
	return
}
func (self CompositionOffset) Len() (n int) {
	n += 8
	n += 1
	n += 3
	n += 4
	n += LenCompositionOffsetEntry*len(self.Entries)
	return
}
func (self *CompositionOffset) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	if len(b) < n+1 {
		err = parseErr("Version", n+offset, err)
		return
	}
	self.Version = pio.U8(b[n:])
	n += 1
	if len(b) < n+3 {
		err = parseErr("Flags", n+offset, err)
		return
	}
	self.Flags = pio.U24BE(b[n:])
	n += 3
	var _len_Entries uint32
	_len_Entries = pio.U32BE(b[n:])
	n += 4
	self.Entries = make([]CompositionOffsetEntry, _len_Entries)
	if len(b) < n+LenCompositionOffsetEntry*len(self.Entries) {
		err = parseErr("CompositionOffsetEntry", n+offset, err)
		return
	}
	for i := range self.Entries {
		self.Entries[i] = GetCompositionOffsetEntry(b[n:])
		n += LenCompositionOffsetEntry
	}
	return
}
func (self CompositionOffset) Children() (r []Atom) {
	return
}

type CompositionOffsetEntry struct {
	Count	uint32
	Offset	uint32
}

func GetCompositionOffsetEntry(b []byte) (self CompositionOffsetEntry) {
	self.Count = pio.U32BE(b[0:])
	self.Offset = pio.U32BE(b[4:])
	return
}
func PutCompositionOffsetEntry(b []byte, self CompositionOffsetEntry) {
	pio.PutU32BE(b[0:], self.Count)
	pio.PutU32BE(b[4:], self.Offset)
}

const LenCompositionOffsetEntry = 8

type SyncSample struct {
	Version	uint8
	Flags	uint32
	Entries	[]uint32
	AtomPos
}

func (self SyncSample) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(STSS))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self SyncSample) marshal(b []byte) (n int) {
	pio.PutU8(b[n:], self.Version)
	n += 1
	pio.PutU24BE(b[n:], self.Flags)
	n += 3
	pio.PutU32BE(b[n:], uint32(len(self.Entries)))
	n += 4
	for _, entry := range self.Entries {
		pio.PutU32BE(b[n:], entry)
		n += 4
	}
	return
}
func (self SyncSample) Len() (n int) {
	n += 8
	n += 1
	n += 3
	n += 4
	n += 4*len(self.Entries)
	return
}
func (self *SyncSample) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	if len(b) < n+1 {
		err = parseErr("Version", n+offset, err)
		return
	}
	self.Version = pio.U8(b[n:])
	n += 1
	if len(b) < n+3 {
		err = parseErr("Flags", n+offset, err)
		return
	}
	self.Flags = pio.U24BE(b[n:])
	n += 3
	var _len_Entries uint32
	_len_Entries = pio.U32BE(b[n:])
	n += 4
	self.Entries = make([]uint32, _len_Entries)
	if len(b) < n+4*len(self.Entries) {
		err = parseErr("uint32", n+offset, err)
		return
	}
	for i := range self.Entries {
		self.Entries[i] = pio.U32BE(b[n:])
		n += 4
	}
	return
}
func (self SyncSample) Children() (r []Atom) {
	return
}

type ChunkOffset struct {
	Version	uint8
	Flags	uint32
	Entries	[]uint32
	AtomPos
}

func (self ChunkOffset) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(STCO))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self ChunkOffset) marshal(b []byte) (n int) {
	pio.PutU8(b[n:], self.Version)
	n += 1
	pio.PutU24BE(b[n:], self.Flags)
	n += 3
	pio.PutU32BE(b[n:], uint32(len(self.Entries)))
	n += 4
	for _, entry := range self.Entries {
		pio.PutU32BE(b[n:], entry)
		n += 4
	}
	return
}
func (self ChunkOffset) Len() (n int) {
	n += 8
	n += 1
	n += 3
	n += 4
	n += 4*len(self.Entries)
	return
}
func (self *ChunkOffset) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	if len(b) < n+1 {
		err = parseErr("Version", n+offset, err)
		return
	}
	self.Version = pio.U8(b[n:])
	n += 1
	if len(b) < n+3 {
		err = parseErr("Flags", n+offset, err)
		return
	}
	self.Flags = pio.U24BE(b[n:])
	n += 3
	var _len_Entries uint32
	_len_Entries = pio.U32BE(b[n:])
	n += 4
	self.Entries = make([]uint32, _len_Entries)
	if len(b) < n+4*len(self.Entries) {
		err = parseErr("uint32", n+offset, err)
		return
	}
	for i := range self.Entries {
		self.Entries[i] = pio.U32BE(b[n:])
		n += 4
	}
	return
}
func (self ChunkOffset) Children() (r []Atom) {
	return
}

type MovieFrag struct {
	Header		*MovieFragHeader
	Tracks		[]*TrackFrag
	Unknowns	[]Atom
	AtomPos
}

func (self MovieFrag) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(MOOF))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self MovieFrag) marshal(b []byte) (n int) {
	if self.Header != nil {
		n += self.Header.Marshal(b[n:])
	}
	for _, atom := range self.Tracks {
		n += atom.Marshal(b[n:])
	}
	for _, atom := range self.Unknowns {
		n += atom.Marshal(b[n:])
	}
	return
}
func (self MovieFrag) Len() (n int) {
	n += 8
	if self.Header != nil {
		n += self.Header.Len()
	}
	for _, atom := range self.Tracks {
		n += atom.Len()
	}
	for _, atom := range self.Unknowns {
		n += atom.Len()
	}
	return
}
func (self *MovieFrag) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	for n+8 < len(b) {
		tag := Tag(pio.U32BE(b[n+4:]))
		size := int(pio.U32BE(b[n:]))
		if len(b) < n+size {
			err = parseErr("TagSizeInvalid", n+offset, err)
			return
		}
		switch tag {
		case MFHD:
			{
				atom := &MovieFragHeader{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("mfhd", n+offset, err)
					return
				}
				self.Header = atom
			}
		case TRAF:
			{
				atom := &TrackFrag{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("traf", n+offset, err)
					return
				}
				self.Tracks = append(self.Tracks, atom)
			}
		default:
			{
				atom := &Dummy{Tag_: tag, Data: b[n:n+size]}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("", n+offset, err)
					return
				}
				self.Unknowns = append(self.Unknowns, atom)
			}
		}
		n += size
	}
	return
}
func (self MovieFrag) Children() (r []Atom) {
	if self.Header != nil {
		r = append(r, self.Header)
	}
	for _, atom := range self.Tracks {
		r = append(r, atom)
	}
	r = append(r, self.Unknowns...)
	return
}

type MovieFragHeader struct {
	Version	uint8
	Flags	uint32
	Seqnum	uint32
	AtomPos
}

func (self MovieFragHeader) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(MFHD))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self MovieFragHeader) marshal(b []byte) (n int) {
	pio.PutU8(b[n:], self.Version)
	n += 1
	pio.PutU24BE(b[n:], self.Flags)
	n += 3
	pio.PutU32BE(b[n:], self.Seqnum)
	n += 4
	return
}
func (self MovieFragHeader) Len() (n int) {
	n += 8
	n += 1
	n += 3
	n += 4
	return
}
func (self *MovieFragHeader) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	if len(b) < n+1 {
		err = parseErr("Version", n+offset, err)
		return
	}
	self.Version = pio.U8(b[n:])
	n += 1
	if len(b) < n+3 {
		err = parseErr("Flags", n+offset, err)
		return
	}
	self.Flags = pio.U24BE(b[n:])
	n += 3
	if len(b) < n+4 {
		err = parseErr("Seqnum", n+offset, err)
		return
	}
	self.Seqnum = pio.U32BE(b[n:])
	n += 4
	return
}
func (self MovieFragHeader) Children() (r []Atom) {
	return
}

type TrackFrag struct {
	Header		*TrackFragHeader
	DecodeTime	*TrackFragDecodeTime
	Run		*TrackFragRun
	Unknowns	[]Atom
	AtomPos
}

func (self TrackFrag) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(TRAF))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self TrackFrag) marshal(b []byte) (n int) {
	if self.Header != nil {
		n += self.Header.Marshal(b[n:])
	}
	if self.DecodeTime != nil {
		n += self.DecodeTime.Marshal(b[n:])
	}
	if self.Run != nil {
		n += self.Run.Marshal(b[n:])
	}
	for _, atom := range self.Unknowns {
		n += atom.Marshal(b[n:])
	}
	return
}
func (self TrackFrag) Len() (n int) {
	n += 8
	if self.Header != nil {
		n += self.Header.Len()
	}
	if self.DecodeTime != nil {
		n += self.DecodeTime.Len()
	}
	if self.Run != nil {
		n += self.Run.Len()
	}
	for _, atom := range self.Unknowns {
		n += atom.Len()
	}
	return
}
func (self *TrackFrag) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	for n+8 < len(b) {
		tag := Tag(pio.U32BE(b[n+4:]))
		size := int(pio.U32BE(b[n:]))
		if len(b) < n+size {
			err = parseErr("TagSizeInvalid", n+offset, err)
			return
		}
		switch tag {
		case TFHD:
			{
				atom := &TrackFragHeader{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("tfhd", n+offset, err)
					return
				}
				self.Header = atom
			}
		case TFDT:
			{
				atom := &TrackFragDecodeTime{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("tfdt", n+offset, err)
					return
				}
				self.DecodeTime = atom
			}
		case TRUN:
			{
				atom := &TrackFragRun{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("trun", n+offset, err)
					return
				}
				self.Run = atom
			}
		default:
			{
				atom := &Dummy{Tag_: tag, Data: b[n:n+size]}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("", n+offset, err)
					return
				}
				self.Unknowns = append(self.Unknowns, atom)
			}
		}
		n += size
	}
	return
}
func (self TrackFrag) Children() (r []Atom) {
	if self.Header != nil {
		r = append(r, self.Header)
	}
	if self.DecodeTime != nil {
		r = append(r, self.DecodeTime)
	}
	if self.Run != nil {
		r = append(r, self.Run)
	}
	r = append(r, self.Unknowns...)
	return
}

type MovieExtend struct {
	Tracks		[]*TrackExtend
	Unknowns	[]Atom
	AtomPos
}

func (self MovieExtend) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(MVEX))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self MovieExtend) marshal(b []byte) (n int) {
	for _, atom := range self.Tracks {
		n += atom.Marshal(b[n:])
	}
	for _, atom := range self.Unknowns {
		n += atom.Marshal(b[n:])
	}
	return
}
func (self MovieExtend) Len() (n int) {
	n += 8
	for _, atom := range self.Tracks {
		n += atom.Len()
	}
	for _, atom := range self.Unknowns {
		n += atom.Len()
	}
	return
}
func (self *MovieExtend) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	for n+8 < len(b) {
		tag := Tag(pio.U32BE(b[n+4:]))
		size := int(pio.U32BE(b[n:]))
		if len(b) < n+size {
			err = parseErr("TagSizeInvalid", n+offset, err)
			return
		}
		switch tag {
		case TREX:
			{
				atom := &TrackExtend{}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("trex", n+offset, err)
					return
				}
				self.Tracks = append(self.Tracks, atom)
			}
		default:
			{
				atom := &Dummy{Tag_: tag, Data: b[n:n+size]}
				if _, err = atom.Unmarshal(b[n:n+size], offset+n); err != nil {
					err = parseErr("", n+offset, err)
					return
				}
				self.Unknowns = append(self.Unknowns, atom)
			}
		}
		n += size
	}
	return
}
func (self MovieExtend) Children() (r []Atom) {
	for _, atom := range self.Tracks {
		r = append(r, atom)
	}
	r = append(r, self.Unknowns...)
	return
}

type TrackExtend struct {
	Version			uint8
	Flags			uint32
	TrackId			uint32
	DefaultSampleDescIdx	uint32
	DefaultSampleDuration	uint32
	DefaultSampleSize	uint32
	DefaultSampleFlags	uint32
	AtomPos
}

func (self TrackExtend) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(TREX))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self TrackExtend) marshal(b []byte) (n int) {
	pio.PutU8(b[n:], self.Version)
	n += 1
	pio.PutU24BE(b[n:], self.Flags)
	n += 3
	pio.PutU32BE(b[n:], self.TrackId)
	n += 4
	pio.PutU32BE(b[n:], self.DefaultSampleDescIdx)
	n += 4
	pio.PutU32BE(b[n:], self.DefaultSampleDuration)
	n += 4
	pio.PutU32BE(b[n:], self.DefaultSampleSize)
	n += 4
	pio.PutU32BE(b[n:], self.DefaultSampleFlags)
	n += 4
	return
}
func (self TrackExtend) Len() (n int) {
	n += 8
	n += 1
	n += 3
	n += 4
	n += 4
	n += 4
	n += 4
	n += 4
	return
}
func (self *TrackExtend) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	if len(b) < n+1 {
		err = parseErr("Version", n+offset, err)
		return
	}
	self.Version = pio.U8(b[n:])
	n += 1
	if len(b) < n+3 {
		err = parseErr("Flags", n+offset, err)
		return
	}
	self.Flags = pio.U24BE(b[n:])
	n += 3
	if len(b) < n+4 {
		err = parseErr("TrackId", n+offset, err)
		return
	}
	self.TrackId = pio.U32BE(b[n:])
	n += 4
	if len(b) < n+4 {
		err = parseErr("DefaultSampleDescIdx", n+offset, err)
		return
	}
	self.DefaultSampleDescIdx = pio.U32BE(b[n:])
	n += 4
	if len(b) < n+4 {
		err = parseErr("DefaultSampleDuration", n+offset, err)
		return
	}
	self.DefaultSampleDuration = pio.U32BE(b[n:])
	n += 4
	if len(b) < n+4 {
		err = parseErr("DefaultSampleSize", n+offset, err)
		return
	}
	self.DefaultSampleSize = pio.U32BE(b[n:])
	n += 4
	if len(b) < n+4 {
		err = parseErr("DefaultSampleFlags", n+offset, err)
		return
	}
	self.DefaultSampleFlags = pio.U32BE(b[n:])
	n += 4
	return
}
func (self TrackExtend) Children() (r []Atom) {
	return
}

type SampleSize struct {
	Version		uint8
	Flags		uint32
	SampleSize	uint32
	Entries		[]uint32
	AtomPos
}

func (self SampleSize) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(STSZ))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self SampleSize) marshal(b []byte) (n int) {
	pio.PutU8(b[n:], self.Version)
	n += 1
	pio.PutU24BE(b[n:], self.Flags)
	n += 3
	pio.PutU32BE(b[n:], self.SampleSize)
	n += 4
	if self.SampleSize != 0 {
		return
	}
	pio.PutU32BE(b[n:], uint32(len(self.Entries)))
	n += 4
	for _, entry := range self.Entries {
		pio.PutU32BE(b[n:], entry)
		n += 4
	}
	return
}
func (self SampleSize) Len() (n int) {
	n += 8
	n += 1
	n += 3
	n += 4
	if self.SampleSize != 0 {
		return
	}
	n += 4
	n += 4*len(self.Entries)
	return
}
func (self *SampleSize) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	if len(b) < n+1 {
		err = parseErr("Version", n+offset, err)
		return
	}
	self.Version = pio.U8(b[n:])
	n += 1
	if len(b) < n+3 {
		err = parseErr("Flags", n+offset, err)
		return
	}
	self.Flags = pio.U24BE(b[n:])
	n += 3
	if len(b) < n+4 {
		err = parseErr("SampleSize", n+offset, err)
		return
	}
	self.SampleSize = pio.U32BE(b[n:])
	n += 4
	if self.SampleSize != 0 {
		return
	}
	var _len_Entries uint32
	_len_Entries = pio.U32BE(b[n:])
	n += 4
	self.Entries = make([]uint32, _len_Entries)
	if len(b) < n+4*len(self.Entries) {
		err = parseErr("uint32", n+offset, err)
		return
	}
	for i := range self.Entries {
		self.Entries[i] = pio.U32BE(b[n:])
		n += 4
	}
	return
}
func (self SampleSize) Children() (r []Atom) {
	return
}

type TrackFragRun struct {
	Version			uint8
	Flags			uint32
	DataOffset		uint32
	FirstSampleFlags	uint32
	Entries			[]TrackFragRunEntry
	AtomPos
}

func (self TrackFragRun) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(TRUN))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self TrackFragRun) marshal(b []byte) (n int) {
	pio.PutU8(b[n:], self.Version)
	n += 1
	pio.PutU24BE(b[n:], self.Flags)
	n += 3
	pio.PutU32BE(b[n:], uint32(len(self.Entries)))
	n += 4
	if self.Flags&TRUN_DATA_OFFSET != 0 {
		{
			pio.PutU32BE(b[n:], self.DataOffset)
			n += 4
		}
	}
	if self.Flags&TRUN_FIRST_SAMPLE_FLAGS != 0 {
		{
			pio.PutU32BE(b[n:], self.FirstSampleFlags)
			n += 4
		}
	}

	for i, entry := range self.Entries {
		var flags uint32
		if i > 0 {
			flags = self.Flags
		} else {
			flags = self.FirstSampleFlags
		}
		if flags&TRUN_SAMPLE_DURATION != 0 {
			pio.PutU32BE(b[n:], entry.Duration)
			n += 4
		}
		if flags&TRUN_SAMPLE_SIZE != 0 {
			pio.PutU32BE(b[n:], entry.Size)
			n += 4
		}
		if flags&TRUN_SAMPLE_FLAGS != 0 {
			pio.PutU32BE(b[n:], entry.Flags)
			n += 4
		}
		if flags&TRUN_SAMPLE_CTS != 0 {
			pio.PutU32BE(b[n:], entry.Cts)
			n += 4
		}
	}
	return
}
func (self TrackFragRun) Len() (n int) {
	n += 8
	n += 1
	n += 3
	n += 4
	if self.Flags&TRUN_DATA_OFFSET != 0 {
		{
			n += 4
		}
	}
	if self.Flags&TRUN_FIRST_SAMPLE_FLAGS != 0 {
		{
			n += 4
		}
	}

	for i := range self.Entries {
		var flags uint32
		if i > 0 {
			flags = self.Flags
		} else {
			flags = self.FirstSampleFlags
		}
		if flags&TRUN_SAMPLE_DURATION != 0 {
			n += 4
		}
		if flags&TRUN_SAMPLE_SIZE != 0 {
			n += 4
		}
		if flags&TRUN_SAMPLE_FLAGS != 0 {
			n += 4
		}
		if flags&TRUN_SAMPLE_CTS != 0 {
			n += 4
		}
	}
	return
}
func (self *TrackFragRun) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	if len(b) < n+1 {
		err = parseErr("Version", n+offset, err)
		return
	}
	self.Version = pio.U8(b[n:])
	n += 1
	if len(b) < n+3 {
		err = parseErr("Flags", n+offset, err)
		return
	}
	self.Flags = pio.U24BE(b[n:])
	n += 3
	var _len_Entries uint32
	_len_Entries = pio.U32BE(b[n:])
	n += 4
	self.Entries = make([]TrackFragRunEntry, _len_Entries)
	if self.Flags&TRUN_DATA_OFFSET != 0 {
		{
			if len(b) < n+4 {
				err = parseErr("DataOffset", n+offset, err)
				return
			}
			self.DataOffset = pio.U32BE(b[n:])
			n += 4
		}
	}
	if self.Flags&TRUN_FIRST_SAMPLE_FLAGS != 0 {
		{
			if len(b) < n+4 {
				err = parseErr("FirstSampleFlags", n+offset, err)
				return
			}
			self.FirstSampleFlags = pio.U32BE(b[n:])
			n += 4
		}
	}

	for i := 0; i < int(_len_Entries); i++ {
		var flags uint32
		if i > 0 {
			flags = self.Flags
		} else {
			flags = self.FirstSampleFlags
		}
		entry := &self.Entries[i]
		if flags&TRUN_SAMPLE_DURATION != 0 {
			entry.Duration = pio.U32BE(b[n:])
			n += 4
		}
		if flags&TRUN_SAMPLE_SIZE != 0 {
			entry.Size = pio.U32BE(b[n:])
			n += 4
		}
		if flags&TRUN_SAMPLE_FLAGS != 0 {
			entry.Flags = pio.U32BE(b[n:])
			n += 4
		}
		if flags&TRUN_SAMPLE_CTS != 0 {
			entry.Cts = pio.U32BE(b[n:])
			n += 4
		}
	}
	return
}
func (self TrackFragRun) Children() (r []Atom) {
	return
}

type TrackFragRunEntry struct {
	Duration	uint32
	Size		uint32
	Flags		uint32
	Cts		uint32
}

func GetTrackFragRunEntry(b []byte) (self TrackFragRunEntry) {
	self.Duration = pio.U32BE(b[0:])
	self.Size = pio.U32BE(b[4:])
	self.Flags = pio.U32BE(b[8:])
	self.Cts = pio.U32BE(b[12:])
	return
}
func PutTrackFragRunEntry(b []byte, self TrackFragRunEntry) {
	pio.PutU32BE(b[0:], self.Duration)
	pio.PutU32BE(b[4:], self.Size)
	pio.PutU32BE(b[8:], self.Flags)
	pio.PutU32BE(b[12:], self.Cts)
}

const LenTrackFragRunEntry = 16

type TrackFragHeader struct {
	Version		uint8
	Flags		uint32
	BaseDataOffset	uint64
	StsdId		uint32
	DefaultDuration	uint32
	DefaultSize	uint32
	DefaultFlags	uint32
	AtomPos
}

func (self TrackFragHeader) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(TFHD))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self TrackFragHeader) marshal(b []byte) (n int) {
	pio.PutU8(b[n:], self.Version)
	n += 1
	pio.PutU24BE(b[n:], self.Flags)
	n += 3
	if self.Flags&TFHD_BASE_DATA_OFFSET != 0 {
		{
			pio.PutU64BE(b[n:], self.BaseDataOffset)
			n += 8
		}
	}
	if self.Flags&TFHD_STSD_ID != 0 {
		{
			pio.PutU32BE(b[n:], self.StsdId)
			n += 4
		}
	}
	if self.Flags&TFHD_DEFAULT_DURATION != 0 {
		{
			pio.PutU32BE(b[n:], self.DefaultDuration)
			n += 4
		}
	}
	if self.Flags&TFHD_DEFAULT_SIZE != 0 {
		{
			pio.PutU32BE(b[n:], self.DefaultSize)
			n += 4
		}
	}
	if self.Flags&TFHD_DEFAULT_FLAGS != 0 {
		{
			pio.PutU32BE(b[n:], self.DefaultFlags)
			n += 4
		}
	}
	return
}
func (self TrackFragHeader) Len() (n int) {
	n += 8
	n += 1
	n += 3
	if self.Flags&TFHD_BASE_DATA_OFFSET != 0 {
		{
			n += 8
		}
	}
	if self.Flags&TFHD_STSD_ID != 0 {
		{
			n += 4
		}
	}
	if self.Flags&TFHD_DEFAULT_DURATION != 0 {
		{
			n += 4
		}
	}
	if self.Flags&TFHD_DEFAULT_SIZE != 0 {
		{
			n += 4
		}
	}
	if self.Flags&TFHD_DEFAULT_FLAGS != 0 {
		{
			n += 4
		}
	}
	return
}
func (self *TrackFragHeader) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	if len(b) < n+1 {
		err = parseErr("Version", n+offset, err)
		return
	}
	self.Version = pio.U8(b[n:])
	n += 1
	if len(b) < n+3 {
		err = parseErr("Flags", n+offset, err)
		return
	}
	self.Flags = pio.U24BE(b[n:])
	n += 3
	if self.Flags&TFHD_BASE_DATA_OFFSET != 0 {
		{
			if len(b) < n+8 {
				err = parseErr("BaseDataOffset", n+offset, err)
				return
			}
			self.BaseDataOffset = pio.U64BE(b[n:])
			n += 8
		}
	}
	if self.Flags&TFHD_STSD_ID != 0 {
		{
			if len(b) < n+4 {
				err = parseErr("StsdId", n+offset, err)
				return
			}
			self.StsdId = pio.U32BE(b[n:])
			n += 4
		}
	}
	if self.Flags&TFHD_DEFAULT_DURATION != 0 {
		{
			if len(b) < n+4 {
				err = parseErr("DefaultDuration", n+offset, err)
				return
			}
			self.DefaultDuration = pio.U32BE(b[n:])
			n += 4
		}
	}
	if self.Flags&TFHD_DEFAULT_SIZE != 0 {
		{
			if len(b) < n+4 {
				err = parseErr("DefaultSize", n+offset, err)
				return
			}
			self.DefaultSize = pio.U32BE(b[n:])
			n += 4
		}
	}
	if self.Flags&TFHD_DEFAULT_FLAGS != 0 {
		{
			if len(b) < n+4 {
				err = parseErr("DefaultFlags", n+offset, err)
				return
			}
			self.DefaultFlags = pio.U32BE(b[n:])
			n += 4
		}
	}
	return
}
func (self TrackFragHeader) Children() (r []Atom) {
	return
}

type TrackFragDecodeTime struct {
	Version	uint8
	Flags	uint32
	Time	time.Time
	AtomPos
}

func (self TrackFragDecodeTime) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(TFDT))
	n += self.marshal(b[8:])+8
	pio.PutU32BE(b[0:], uint32(n))
	return
}
func (self TrackFragDecodeTime) marshal(b []byte) (n int) {
	pio.PutU8(b[n:], self.Version)
	n += 1
	pio.PutU24BE(b[n:], self.Flags)
	n += 3
	if self.Version != 0 {
		PutTime64(b[n:], self.Time)
		n += 8
	} else {

		PutTime32(b[n:], self.Time)
		n += 4
	}
	return
}
func (self TrackFragDecodeTime) Len() (n int) {
	n += 8
	n += 1
	n += 3
	if self.Version != 0 {
		n += 8
	} else {

		n += 4
	}
	return
}
func (self *TrackFragDecodeTime) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	if len(b) < n+1 {
		err = parseErr("Version", n+offset, err)
		return
	}
	self.Version = pio.U8(b[n:])
	n += 1
	if len(b) < n+3 {
		err = parseErr("Flags", n+offset, err)
		return
	}
	self.Flags = pio.U24BE(b[n:])
	n += 3
	if self.Version != 0 {
		self.Time = GetTime64(b[n:])
		n += 8
	} else {

		self.Time = GetTime32(b[n:])
		n += 4
	}
	return
}
func (self TrackFragDecodeTime) Children() (r []Atom) {
	return
}


================================================
FILE: format/mp4/mp4io/gen/gen.go
================================================

package main

import (
	"strings"
	"fmt"
	"os"
	"go/ast"
	"go/parser"
	"go/token"
	"go/printer"
)

func getexprs(e ast.Expr) string {
	if lit, ok := e.(*ast.BasicLit); ok {
		return lit.Value
	}
	if ident, ok := e.(*ast.Ident); ok {
		return ident.Name
	}
	return ""
}

func genatomdecl(origfn *ast.FuncDecl, origname, origtag string) (decls []ast.Decl) {
	fieldslist := &ast.FieldList{}
	typespec := &ast.TypeSpec{
		Name: ast.NewIdent(origname),
		Type: &ast.StructType{Fields: fieldslist},
	}

	for _, _stmt := range origfn.Body.List {
		stmt := _stmt.(*ast.ExprStmt)
		callexpr := stmt.X.(*ast.CallExpr)
		typ := callexpr.Fun.(*ast.Ident).Name

		if strings.HasPrefix(typ, "_") {
			if typ == "_unknowns" {
				fieldslist.List = append(fieldslist.List, &ast.Field{
					Names: []*ast.Ident{ast.NewIdent("Unknowns")},
					Type: ast.NewIdent("[]Atom"),
				})
			}
			continue
		}

		name := getexprs(callexpr.Args[0])

		name2 := ""
		if len(callexpr.Args) > 1 {
			name2 = getexprs(callexpr.Args[1])
		}

		len3 := ""
		if len(callexpr.Args) > 2 {
			len3 = getexprs(callexpr.Args[2])
		}

		if strings.HasPrefix(name, "_") {
			continue
		}

		switch typ {
		case "fixed16":
			typ = "float64"
		case "fixed32":
			typ = "float64"
		case "bytesleft":
			typ = "[]byte"
		case "bytes":
			typ = "["+name2+"]byte"
		case "uint24":
			typ = "uint32"
		case "time64", "time32":
			typ = "time.Time"
		case "atom":
			typ = "*"+name2
		case "atoms":
			typ = "[]*"+name2
		case "slice":
			typ = "[]"+name2
		case "array":
			typ = "["+len3+"]"+name2
		}

		fieldslist.List = append(fieldslist.List, &ast.Field{
			Names: []*ast.Ident{ast.NewIdent(name)},
			Type: ast.NewIdent(typ),
		})
	}

	if origtag != "" {
		fieldslist.List = append(fieldslist.List, &ast.Field{
			Type: ast.NewIdent("AtomPos"),
		})
	}

	gendecl := &ast.GenDecl{
		Tok: token.TYPE,
		Specs: []ast.Spec{
			typespec,
		},
	}
	decls = append(decls, gendecl)
	return
}

func typegetlen(typ string) (n int) {
	switch typ {
	case "uint8":
		n = 1
	case "uint16":
		n = 2
	case "uint24":
		n = 3
	case "uint32":
		n = 4
	case "int16":
		n = 2
	case "int32":
		n = 4
	case "uint64":
		n = 8
	case "time32":
		n = 4
	case "time64":
		n = 8
	case "fixed32":
		n = 4
	case "fixed16":
		n = 2
	}
	return
}

func typegetlens(typ string) string {
	n := typegetlen(typ)
	if n == 0 {
		return "Len"+typ
	} else {
		return fmt.Sprint(n)
	}
}

func typegetvartype(typ string) string {
	switch typ {
	case "uint8":
		return "uint8"
	case "uint16":
		return "uint16"
	case "uint24":
		return "uint32"
	case "uint32":
		return "uint32"
	case "uint64":
		return "uint64"
	case "int16":
		return "int16"
	case "int32":
		return "int32"
	}
	return ""
}

func typegetputfn(typ string) (fn string) {
	fn = typ
	switch typ {
	case "uint8":
		fn = "pio.PutU8"
	case "uint16":
		fn = "pio.PutU16BE"
	case "uint24":
		fn = "pio.PutU24BE"
	case "uint32":
		fn = "pio.PutU32BE"
	case "int16":
		fn = "pio.PutI16BE"
	case "int32":
		fn = "pio.PutI32BE"
	case "uint64":
		fn = "pio.PutU64BE"
	case "time32":
		fn = "PutTime32"
	case "time64":
		fn = "PutTime64"
	case "fixed32":
		fn = "PutFixed32"
	case "fixed16":
		fn = "PutFixed16"
	default:
		fn = "Put"+typ
	}
	return
}

func typegetgetfn(typ string) (fn string) {
	fn = typ
	switch typ {
	case "uint8":
		fn = "pio.U8"
	case "uint16":
		fn = "pio.U16BE"
	case "uint24":
		fn = "pio.U24BE"
	case "uint32":
		fn = "pio.U32BE"
	case "int16":
		fn = "pio.I16BE"
	case "int32":
		fn = "pio.I32BE"
	case "uint64":
		fn = "pio.U64BE"
	case "time32":
		fn = "GetTime32"
	case "time64":
		fn = "GetTime64"
	case "fixed32":
		fn = "GetFixed32"
	case "fixed16":
		fn = "GetFixed16"
	default:
		fn = "Get"+typ
	}
	return
}

func addns(n string) (stmts []ast.Stmt) {
	assign := &ast.AssignStmt{
		Tok: token.ADD_ASSIGN,
		Lhs: []ast.Expr{ast.NewIdent("n")},
		Rhs: []ast.Expr{&ast.BasicLit{Kind: token.INT, Value: n}},
	}
	stmts = append(stmts, assign)
	return
}

func addn(n int) (stmts []ast.Stmt) {
	return addns(fmt.Sprint(n))
}

func simplecall(fun string, args... string) *ast.ExprStmt {
	_args := []ast.Expr{}
	for _, s := range args {
		_args = append(_args, ast.NewIdent(s))
	}
	return &ast.ExprStmt{
		X: &ast.CallExpr{
			Fun: ast.NewIdent(fun),
			Args: _args,
		},
	}
}

func getxx(typ string, pos, name string, conv bool) (stmts []ast.Stmt) {
	fn := typegetgetfn(typ)
	assign := &ast.AssignStmt{
		Tok: token.ASSIGN,
		Lhs: []ast.Expr{ast.NewIdent(name)},
		Rhs: []ast.Expr{simplecall(fn, "b["+pos+":]").X},
	}
	stmts = append(stmts, assign)
	return
}

func putxx(typ string, pos, name string, conv bool) (stmts []ast.Stmt) {
	if conv {
		name = fmt.Sprintf("%s(%s)", typ, name)
	}
	fn := typegetputfn(typ)
	stmts = append(stmts, simplecall(fn, "b["+pos+":]", name))
	return
}

func putxxadd(fn string, name string, conv bool) (stmts []ast.Stmt) {
	n := typegetlen(fn)
	stmts = append(stmts, putxx(fn, "n", name, conv)...)
	stmts = append(stmts, addn(n)...)
	return
}

func newdecl(origname, name string, params, res []*ast.Field, stmts []ast.Stmt) *ast.FuncDecl {
	return &ast.FuncDecl{
		Recv: &ast.FieldList{
			List: []*ast.Field{
				&ast.Field{
					Names: []*ast.Ident{ast.NewIdent("self")},
					Type: ast.NewIdent(origname),
				},
			},
		},
		Name: ast.NewIdent(name),
		Type: &ast.FuncType{
			Params: &ast.FieldList{
				List: params,
			},
			Results: &ast.FieldList{
				List: res,
			},
		},
		Body: &ast.BlockStmt{List: stmts},
	}
}

func getstructputgetlenfn(origfn *ast.FuncDecl, origname string) (decls []ast.Decl) {
	getstmts := []ast.Stmt{}
	putstmts := []ast.Stmt{}
	totlen := 0

	for _, _stmt := range origfn.Body.List {
		stmt := _stmt.(*ast.ExprStmt)
		callexpr := stmt.X.(*ast.CallExpr)
		typ := callexpr.Fun.(*ast.Ident).Name
		name := getexprs(callexpr.Args[0])

		getstmts = append(getstmts, getxx(typ, fmt.Sprint(totlen), "self."+name, false)...)
		putstmts = append(putstmts, putxx(typ, fmt.Sprint(totlen), "self."+name, false)...)
		totlen += typegetlen(typ)
	}

	getstmts = append(getstmts, &ast.ReturnStmt{})

	decls = append(decls, &ast.FuncDecl{
		Name: ast.NewIdent("Get"+origname),
		Type: &ast.FuncType{
			Params: &ast.FieldList{
				List: []*ast.Field{
					&ast.Field{Names: []*ast.Ident{ast.NewIdent("b")}, Type: ast.NewIdent("[]byte")},
				},
			},
			Results: &ast.FieldList{
				List: []*ast.Field{
					&ast.Field{Names: []*ast.Ident{ast.NewIdent("self")}, Type: ast.NewIdent(origname)},
				},
			},
		},
		Body: &ast.BlockStmt{List: getstmts},
	})

	decls = append(decls, &ast.FuncDecl{
		Name: ast.NewIdent("Put"+origname),
		Type: &ast.FuncType{
			Params: &ast.FieldList{
				List: []*ast.Field{
					&ast.Field{Names: []*ast.Ident{ast.NewIdent("b")}, Type: ast.NewIdent("[]byte")},
					&ast.Field{Names: []*ast.Ident{ast.NewIdent("self")}, Type: ast.NewIdent(origname)},
				},
			},
		},
		Body: &ast.BlockStmt{List: putstmts},
	})

	decls = append(decls, &ast.GenDecl{
		Tok: token.CONST,
		Specs: []ast.Spec{
			&ast.ValueSpec{
				Names: []*ast.Ident{ast.NewIdent("Len"+origname)},
				Values: []ast.Expr{ast.NewIdent(fmt.Sprint(totlen))},
			},
		},
	})

	return
}

func cc4decls(name string) (decls []ast.Decl) {
	constdecl := &ast.GenDecl{
		Tok: token.CONST,
		Specs: []ast.Spec{
			&ast.ValueSpec{
				Names: []*ast.Ident{
					ast.NewIdent(strings.ToUpper(name)),
				},
				Values: []ast.Expr{
					&ast.CallExpr{
						Fun: ast.NewIdent("Tag"),
						Args: []ast.Expr{&ast.BasicLit{Kind: token.INT, Value: fmt.Sprintf("0x%x", []byte(name))}},
					},
				},
			},
		},
	}
	decls = append(decls, constdecl)
	return
}

func codeclonereplace(stmts []ast.Stmt, doit []ast.Stmt) (out []ast.Stmt) {
	out = append([]ast.Stmt(nil), stmts...)
	for i := range out {
		if ifstmt, ok := out[i].(*ast.IfStmt); ok {
			newifstmt := &ast.IfStmt{
				Cond: ifstmt.Cond,
				Body: &ast.BlockStmt{
					List: codeclonereplace(ifstmt.Body.List, doit),
				},
			}
			if ifstmt.Else != nil {
				newifstmt.Else = &ast.BlockStmt{
					List: codeclonereplace(ifstmt.Else.(*ast.BlockStmt).List, doit),
				}
			}
			out[i] = newifstmt
		} else if exprstmt, ok := out[i].(*ast.ExprStmt); ok {
			if callexpr, ok := exprstmt.X.(*ast.CallExpr); ok {
				if getexprs(callexpr.Fun) == "doit" {
					out[i] = &ast.BlockStmt{List: doit}
				}
			}
		}
	}
	return
}

func getatommarshalfn(origfn *ast.FuncDecl,
	origname, origtag string,
	tagnamemap map[string]string,
) (decls []ast.Decl) {
	marstmts := []ast.Stmt{}
	unmarstmts := []ast.Stmt{}
	lenstmts := []ast.Stmt{}
	childrenstmts := []ast.Stmt{}

	parseerrreturn := func(debug string) (stmts []ast.Stmt) {
		return []ast.Stmt{
			&ast.AssignStmt{
				Tok: token.ASSIGN,
				Lhs: []ast.Expr{ast.NewIdent("err")},
				Rhs: []ast.Expr{ast.NewIdent(fmt.Sprintf(`parseErr("%s", n+offset, err)`, debug))},
			},
			&ast.ReturnStmt{},
		}
	}

	callmarshal := func(name string) (stmts []ast.Stmt) {
		callexpr := &ast.CallExpr{
			Fun: ast.NewIdent(name+".Marshal"),
			Args: []ast.Expr{ast.NewIdent("b[n:]")},
		}
		assign := &ast.AssignStmt{
			Tok: token.ADD_ASSIGN,
			Lhs: []ast.Expr{ast.NewIdent("n")},
			Rhs: []ast.Expr{callexpr},
		}
		stmts = append(stmts, assign)
		return
	}

	callputstruct := func(typ, name string) (stmts []ast.Stmt) {
		stmts = append(stmts, &ast.ExprStmt{
			X: &ast.CallExpr{
				Fun: ast.NewIdent(typegetputfn(typ)),
				Args: []ast.Expr{ast.NewIdent("b[n:]"), ast.NewIdent(name)},
			},
		})
		stmts = append(stmts, &ast.AssignStmt{
			Tok: token.ADD_ASSIGN,
			Lhs: []ast.Expr{ast.NewIdent("n")},
			Rhs: []ast.Expr{ast.NewIdent(typegetlens(typ))},
		})
		return
	}

	calllenstruct := func(typ, name string) (stmts []ast.Stmt) {
		inc := typegetlens(typ)+"*len("+name+")"
		stmts = append(stmts, &ast.AssignStmt{
			Tok: token.ADD_ASSIGN,
			Lhs: []ast.Expr{ast.NewIdent("n")},
			Rhs: []ast.Expr{ast.NewIdent(inc)},
		})
		return
	}

	calllen := func(name string) (stmts []ast.Stmt) {
		callexpr := &ast.CallExpr{
			Fun: ast.NewIdent(name+".Len"),
			Args: []ast.Expr{},
		}
		assign := &ast.AssignStmt{
			Tok: token.ADD_ASSIGN,
			Lhs: []ast.Expr{ast.NewIdent("n")},
			Rhs: []ast.Expr{callexpr},
		}
		stmts = append(stmts, assign)
		return
	}

	foreach := func(name, field string, block []ast.Stmt) (stmts []ast.Stmt) {
		rangestmt := &ast.RangeStmt{
			Key: ast.NewIdent("_"),
			Value: ast.NewIdent(name),
			Body: &ast.BlockStmt{
				List: block,
			},
			Tok: token.DEFINE,
			X: ast.NewIdent(field),
		}
		stmts = append(stmts, rangestmt)
		return
	}

	foreachatom := func(field string, block []ast.Stmt) (stmts []ast.Stmt) {
		return foreach("atom", field, block)
	}

	foreachentry := func(field string, block []ast.Stmt) (stmts []ast.Stmt) {
		return foreach("entry", field, block)
	}

	foreachi := func(field string, block []ast.Stmt) (stmts []ast.Stmt) {
		rangestmt := &ast.RangeStmt{
			Key: ast.NewIdent("i"),
			Body: &ast.BlockStmt{
				List: block,
			},
			Tok: token.DEFINE,
			X: ast.NewIdent(field),
		}
		stmts = append(stmts, rangestmt)
		return
	}

	foreachunknowns := func(block []ast.Stmt) (stmts []ast.Stmt) {
		return foreachatom("self.Unknowns", block)
	}

	declvar := func(name, typ string) (stmts []ast.Stmt) {
		stmts = append(stmts, &ast.DeclStmt{
			Decl: &ast.GenDecl{
				Tok: token.VAR,
				Specs: []ast.Spec{
					&ast.ValueSpec{
						Names: []*ast.Ident{
							ast.NewIdent(typ),
						},
						Type: ast.NewIdent(name),
					},
				},
			},
		})
		return
	}

	makeslice := func(name, typ, size string) (stmts []ast.Stmt) {
		stmts = append(stmts, &ast.ExprStmt{
			X: ast.NewIdent(fmt.Sprintf("%s = make([]%s, %s)", name, typ, size)),
		})
		return
	}

	simpleassign := func(tok token.Token, l, r string) *ast.AssignStmt {
		return &ast.AssignStmt{
			Tok: tok,
			Lhs: []ast.Expr{ast.NewIdent(l)},
			Rhs: []ast.Expr{ast.NewIdent(r)},
		}
	}

	struct2tag := func(s string) string {
		name := tagnamemap[s]
		return name
	}

	foreachatomsappendchildren := func(field string) (stmts []ast.Stmt) {
		return foreachatom(field, []ast.Stmt{
			simpleassign(token.ASSIGN, "r", "append(r, atom)"),
		})
	}

	var hasunknowns bool
	var atomnames []string
	var atomtypes []string
	var atomarrnames []string
	var atomarrtypes []string
	slicenamemap := map[string]string{}

	unmarshalatom := func(typ, init string) (stmts []ast.Stmt) {
		return []ast.Stmt{
			&ast.AssignStmt{Tok: token.DEFINE,
				Lhs: []ast.Expr{ast.NewIdent("atom")}, Rhs: []ast.Expr{ast.NewIdent("&"+typ+"{"+init+"}")},
			},
			&ast.IfStmt{
				Init: &ast.AssignStmt{
					Tok: token.ASSIGN,
					Lhs: []ast.Expr{ast.NewIdent("_"), ast.NewIdent("err")},
					Rhs: []ast.Expr{ast.NewIdent("atom.Unmarshal(b[n:n+size], offset+n)")},
				},
				Cond: ast.NewIdent("err != nil"),
				Body: &ast.BlockStmt{List: parseerrreturn(struct2tag(typ))},
			},
		}
	}

	unmrashalatoms := func() (stmts []ast.Stmt) {
		blocks := []ast.Stmt{}

		blocks = append(blocks, &ast.AssignStmt{ Tok: token.DEFINE, Lhs: []ast.Expr{ast.NewIdent("tag")},
			Rhs: []ast.Expr{ast.NewIdent("Tag(pio.U32BE(b[n+4:]))")},
		})
		blocks = append(blocks, &ast.AssignStmt{ Tok: token.DEFINE, Lhs: []ast.Expr{ast.NewIdent("size")},
			Rhs: []ast.Expr{ast.NewIdent("int(pio.U32BE(b[n:]))")},
		})
		blocks = append(blocks, &ast.IfStmt{
			Cond: ast.NewIdent("len(b) < n+size"),
			Body: &ast.BlockStmt{List: parseerrreturn("TagSizeInvalid")},
		})

		cases := []ast.Stmt{}

		for i, atom := range atomnames {
			cases = append(cases, &ast.CaseClause{
				List: []ast.Expr{ast.NewIdent(strings.ToUpper(struct2tag(atomtypes[i])))},
				Body: []ast.Stmt{&ast.BlockStmt{
					List: append(unmarshalatom(atomtypes[i], ""), simpleassign(token.ASSIGN, "self."+atom, "atom")),
				}},
			})
		}

		for i, atom := range atomarrnames {
			selfatom := "self."+atom
			cases = append(cases, &ast.CaseClause{
				List: []ast.Expr{ast.NewIdent(strings.ToUpper(struct2tag(atomarrtypes[i])))},
				Body: []ast.Stmt{&ast.BlockStmt{
					List: append(unmarshalatom(atomarrtypes[i], ""),
						simpleassign(token.ASSIGN, selfatom, "append("+selfatom+", atom)")),
				}},
			})
		}

		if hasunknowns {
			init := "Tag_: tag, Data: b[n:n+size]"
			selfatom := "self.Unknowns"
			cases = append(cases, &ast.CaseClause{
				Body: []ast.Stmt{&ast.BlockStmt{
					List: append(unmarshalatom("Dummy", init), simpleassign(token.ASSIGN, selfatom, "append("+selfatom+", atom)")),
				}},
			})
		}

		blocks = append(blocks, &ast.SwitchStmt{
			Tag: ast.NewIdent("tag"),
			Body: &ast.BlockStmt{List: cases},
		})

		blocks = append(blocks, addns("size")...)

		stmts = append(stmts, &ast.ForStmt{
			Cond: ast.NewIdent("n+8 < len(b)"),
			Body: &ast.BlockStmt{List: blocks},
		})
		return
	}

	marshalwrapstmts := func() (stmts []ast.Stmt) {
		stmts = append(stmts, putxx("uint32", "4", strings.ToUpper(origtag), true)...)
		stmts = append(stmts, addns("self.marshal(b[8:])+8")...)
		stmts = append(stmts, putxx("uint32", "0", "n", true)...)
		stmts = append(stmts, &ast.ReturnStmt{})
		return
	}

	ifnotnil := func(name string, block []ast.Stmt) (stmts []ast.Stmt) {
		stmts = append(stmts, &ast.IfStmt{
			Cond: &ast.BinaryExpr{
				X: ast.NewIdent(name),
				Op: token.NEQ,
				Y: ast.NewIdent("nil"),
			},
			Body: &ast.BlockStmt{List: block},
		})
		return
	}

	getchildrennr := func(name string) (stmts []ast.Stmt) {
		stmts = append(stmts, &ast.AssignStmt{
			Tok: token.DEFINE,
			Lhs: []ast.Expr{ast.NewIdent(name)},
			Rhs: []ast.Expr{ast.NewIdent("0")},
		})
		for _, atom := range atomnames {
			stmts = append(stmts, ifnotnil("self."+atom, []ast.Stmt{
				&ast.IncDecStmt{X: ast.NewIdent(name), Tok: token.INC},
			})...)
		}
		if hasunknowns {
			assign := &ast.AssignStmt{
				Tok: token.ADD_ASSIGN,
				Lhs: []ast.Expr{ast.NewIdent("_childrenNR")},
				Rhs: []ast.Expr{ast.NewIdent("len(self.Unknowns)")},
			}
			stmts = append(stmts, assign)
		}
		return
	}

	checkcurlen := func(inc, debug string) (stmts []ast.Stmt) {
		stmts = append(stmts, &ast.IfStmt{
			Cond: &ast.BinaryExpr{
				X: ast.NewIdent("len(b)"),
				Op: token.LSS,
				Y: ast.NewIdent("n+"+inc),
			},
			Body: &ast.BlockStmt{List: parseerrreturn(debug)},
		})
		return
	}

	checklendo := func(typ, name, debug string) (stmts []ast.Stmt) {
		stmts = append(stmts, checkcurlen(typegetlens(typ), debug)...)
		stmts = append(stmts, getxx(typ, "n", name, false)...)
		stmts = append(stmts, addns(typegetlens(typ))...)
		return
	}

	checkstructlendo := func(typ, name, debug string,
		foreach func(string,[]ast.Stmt)[]ast.Stmt,
	) (stmts []ast.Stmt) {
		inc := typegetlens(typ)+"*len("+name+")"
		stmts = append(stmts, checkcurlen(inc, debug)...)
		stmts = append(stmts, foreach(name, append(
			[]ast.Stmt{
				&ast.AssignStmt{
					Tok: token.ASSIGN,
					Lhs: []ast.Expr{
						ast.NewIdent(name+"[i]"),
					},
					Rhs: []ast.Expr{
						&ast.CallExpr{
							Fun: ast.NewIdent(typegetgetfn(typ)),
							Args: []ast.Expr{ast.NewIdent("b[n:]")},
						},
					},
				},
			},
			addns(typegetlens(typ))...,
		))...)
		return
	}

	checklencopy := func(name string) (stmts []ast.Stmt) {
		lens := fmt.Sprintf("len(self.%s)", name)
		stmts = append(stmts, checkcurlen(lens, name)...)
		stmts = append(stmts, simplecall("copy", fmt.Sprintf("self.%s[:]", name), "b[n:]"))
		stmts = append(stmts, addns(lens)...)
		return
	}

	appendcode := func(args []ast.Expr,
		marstmts *[]ast.Stmt, lenstmts *[]ast.Stmt, unmarstmts *[]ast.Stmt,
		defmarstmts []ast.Stmt, deflenstmts []ast.Stmt, defunmarstmts []ast.Stmt,
	) {
		bodylist := func(i int, doit []ast.Stmt) []ast.Stmt {
			return codeclonereplace(args[i].(*ast.FuncLit).Body.List, doit)
		}
		if len(args) == 1 {
			*marstmts = append(*marstmts, bodylist(0, defmarstmts)...)
			*lenstmts = append(*lenstmts, bodylist(0, deflenstmts)...)
			*unmarstmts = append(*unmarstmts, bodylist(0, defunmarstmts)...)
		} else {
			*marstmts = append(*marstmts, bodylist(0, defmarstmts)...)
			*lenstmts = append(*lenstmts, bodylist(1, deflenstmts)...)
			*unmarstmts = append(*unmarstmts, bodylist(2, defunmarstmts)...)
		}
	}

	getdefaultstmts := func(
		typ, name, name2 string,
		marstmts *[]ast.Stmt, lenstmts *[]ast.Stmt,
		unmarstmts *[]ast.Stmt, childrenstmts *[]ast.Stmt,
	) {
		switch typ {
		case "bytes", "bytesleft":
			*marstmts = append(*marstmts, simplecall("copy", "b[n:]", "self."+name+"[:]"))
			*marstmts = append(*marstmts, addns(fmt.Sprintf("len(self.%s[:])", name))...)
			*lenstmts = append(*lenstmts, addns(fmt.Sprintf("len(self.%s[:])", name))...)
			if typ == "bytes" {
				*unmarstmts = append(*unmarstmts, checklencopy(name)...)
			} else {
				*unmarstmts = append(*unmarstmts, simpleassign(token.ASSIGN, "self."+name, "b[n:]"))
				*unmarstmts = append(*unmarstmts, addns("len(b[n:])")...)
			}

		case "array":
			*marstmts = append(*marstmts, foreachentry("self."+name, callputstruct(name2, "entry"))...)
			*lenstmts = append(*lenstmts, calllenstruct(name2, "self."+name+"[:]")...)
			*unmarstmts = append(*unmarstmts, checkstructlendo(name2, "self."+name, name, foreachi)...)

		case "atoms":
			*marstmts = append(*marstmts, foreachatom("self."+name, callmarshal("atom"))...)
			*lenstmts = append(*lenstmts, foreachatom("self."+name, calllen("atom"))...)
			*childrenstmts = append(*childrenstmts, foreachatomsappendchildren("self."+name)...)

		case "slice":
			*marstmts = append(*marstmts, foreachentry("self."+name, callputstruct(name2, "entry"))...)
			*lenstmts = append(*lenstmts, calllenstruct(name2, "self."+name)...)
			*unmarstmts = append(*unmarstmts, checkstructlendo(name2, "self."+name, name2, foreachi)...)

		case "atom":
			*marstmts = append(*marstmts, ifnotnil("self."+name, callmarshal("self."+name))...)
			*lenstmts = append(*lenstmts, ifnotnil("self."+name, calllen("self."+name))...)
			*childrenstmts = append(*childrenstmts, ifnotnil("self."+name, []ast.Stmt{
				simpleassign(token.ASSIGN, "r", fmt.Sprintf("append(r, %s)", "self."+name)),
			})...)

		default:
			*marstmts = append(*marstmts, putxxadd(typ, "self."+name, false)...)
			*lenstmts = append(*lenstmts, addn(typegetlen(typ))...)
			*unmarstmts = append(*unmarstmts, checklendo(typ, "self."+name, name)...)
		}
	}

	for _, _stmt := range origfn.Body.List {
		stmt := _stmt.(*ast.ExprStmt)
		callexpr := stmt.X.(*ast.CallExpr)
		typ := callexpr.Fun.(*ast.Ident).Name
		if typ == "_unknowns" {
			hasunknowns = true
		} else if typ == "atom" {
			name := getexprs(callexpr.Args[0])
			name2 := getexprs(callexpr.Args[1])
			atomnames = append(atomnames, name)
			atomtypes = append(atomtypes, name2)
		} else if typ == "atoms" {
			name := getexprs(callexpr.Args[0])
			name2 := getexprs(callexpr.Args[1])
			atomarrnames = append(atomarrnames, name)
			atomarrtypes = append(atomarrtypes, name2)
		} else if typ == "slice" {
			name := getexprs(callexpr.Args[0])
			name2 := getexprs(callexpr.Args[1])
			slicenamemap[name] = name2
		}
	}

	lenstmts = append(lenstmts, addn(8)...)
	unmarstmts = append(unmarstmts, simplecall("(&self.AtomPos).setPos", "offset", "len(b)"))
	unmarstmts = append(unmarstmts, addn(8)...)

	for _, _stmt := range origfn.Body.List {
		stmt := _stmt.(*ast.ExprStmt)
		callexpr := stmt.X.(*ast.CallExpr)
		typ := callexpr.Fun.(*ast.Ident).Name

		name := ""
		if len(callexpr.Args) > 0 {
			name = getexprs(callexpr.Args[0])
		}

		name2 := ""
		if len(callexpr.Args) > 1 {
			name2 = getexprs(callexpr.Args[1])
		}

		var defmarstmts, deflenstmts, defunmarstmts, defchildrenstmts []ast.Stmt
		getdefaultstmts(typ, name, name2,
			&defmarstmts, &deflenstmts, &defunmarstmts, &defchildrenstmts)

		var code []ast.Expr
		for _, arg := range callexpr.Args {
			if fn, ok := arg.(*ast.CallExpr); ok {
				if getexprs(fn.Fun) == "_code" {
					code = fn.Args
				}
			}
		}
		if code != nil {
			appendcode(code,
				&marstmts, &lenstmts, &unmarstmts,
				defmarstmts, deflenstmts, defunmarstmts,
			)
			continue
		}

		if strings.HasPrefix(typ, "_") {
			if typ == "_unknowns" {
				marstmts = append(marstmts, foreachunknowns(callmarshal("atom"))...)
				lenstmts = append(lenstmts, foreachunknowns(calllen("atom"))...)
				childrenstmts = append(childrenstmts, simpleassign(token.ASSIGN, "r", "append(r, self.Unknowns...)"))
			}
			if typ == "_skip" {
				marstmts = append(marstmts, addns(name)...)
				lenstmts = append(lenstmts, addns(name)...)
				unmarstmts = append(unmarstmts, addns(name)...)
			}
			if typ == "_code" {
				appendcode(callexpr.Args,
					&marstmts, &lenstmts, &unmarstmts,
					defmarstmts, deflenstmts, defunmarstmts,
				)
			}
			continue
		}

		if name == "_childrenNR" {
			marstmts = append(marstmts, getchildrennr(name)...)
			marstmts = append(marstmts, putxxadd(typ, name, true)...)
			lenstmts = append(lenstmts, addn(typegetlen(typ))...)
			unmarstmts = append(unmarstmts, addn(typegetlen(typ))...)
			continue
		}

		if strings.HasPrefix(name, "_len_") {
			field := name[len("_len_"):]
			marstmts = append(marstmts, putxxadd(typ, "len(self."+field+")", true)...)
			lenstmts = append(lenstmts, addn(typegetlen(typ))...)
			unmarstmts = append(unmarstmts, declvar(typegetvartype(typ), name)...)
			unmarstmts = append(unmarstmts, getxx(typ, "n", name, false)...)
			unmarstmts = append(unmarstmts, addn(typegetlen(typ))...)
			unmarstmts = append(unmarstmts, makeslice("self."+field, slicenamemap[field], name)...)
			continue
		}

		marstmts = append(marstmts, defmarstmts...)
		lenstmts = append(lenstmts, deflenstmts...)
		unmarstmts = append(unmarstmts, defunmarstmts...)
		childrenstmts = append(childrenstmts, defchildrenstmts...)
	}

	if len(atomnames) > 0 || len(atomarrnames) > 0 || hasunknowns {
		unmarstmts = append(unmarstmts, unmrashalatoms()...)
	}

	marstmts = append(marstmts, &ast.ReturnStmt{})
	lenstmts = append(lenstmts, &ast.ReturnStmt{})
	unmarstmts = append(unmarstmts, &ast.ReturnStmt{})
	childrenstmts = append(childrenstmts, &ast.ReturnStmt{})

	decls = append(decls, newdecl(origname, "Marshal", []*ast.Field{
		&ast.Field{Names: []*ast.Ident{ast.NewIdent("b")}, Type: ast.NewIdent("[]byte")},
	}, []*ast.Field{
		&ast.Field{Names: []*ast.Ident{ast.NewIdent("n")}, Type: ast.NewIdent("int")},
	}, marshalwrapstmts()))

	decls = append(decls, newdecl(origname, "marshal", []*ast.Field{
		&ast.Field{Names: []*ast.Ident{ast.NewIdent("b")}, Type: ast.NewIdent("[]byte")},
	}, []*ast.Field{
		&ast.Field{Names: []*ast.Ident{ast.NewIdent("n")}, Type: ast.NewIdent("int")},
	}, marstmts))

	decls = append(decls, newdecl(origname, "Len", []*ast.Field{}, []*ast.Field{
		&ast.Field{Names: []*ast.Ident{ast.NewIdent("n")}, Type: ast.NewIdent("int")},
	}, lenstmts))

	decls = append(decls, newdecl("*"+origname, "Unmarshal", []*ast.Field{
		&ast.Field{Names: []*ast.Ident{ast.NewIdent("b")}, Type: ast.NewIdent("[]byte")},
		&ast.Field{Names: []*ast.Ident{ast.NewIdent("offset")}, Type: ast.NewIdent("int")},
	}, []*ast.Field{
		&ast.Field{Names: []*ast.Ident{ast.NewIdent("n")}, Type: ast.NewIdent("int")},
		&ast.Field{Names: []*ast.Ident{ast.NewIdent("err")}, Type: ast.NewIdent("error")},
	}, unmarstmts))

	decls = append(decls, newdecl(origname, "Children", []*ast.Field{}, []*ast.Field{
		&ast.Field{Names: []*ast.Ident{ast.NewIdent("r")}, Type: ast.NewIdent("[]Atom")},
	}, childrenstmts))

	return
}

func genatoms(filename, outfilename string) {
	// Create the AST by parsing src.
	fset := token.NewFileSet() // positions are relative to fset
	file, err := parser.ParseFile(fset, filename, nil, 0)
	if err != nil {
		panic(err)
	}

	gen := &ast.File{}
	gen.Name = ast.NewIdent("mp4io")
	gen.Decls = []ast.Decl{
		&ast.GenDecl{
			Tok: token.IMPORT,
			Specs: []ast.Spec{
				&ast.ImportSpec{Path: &ast.BasicLit{Kind: token.STRING, Value: `"github.com/nareix/joy4/utils/bits/pio"`}},
			},
		},
		&ast.GenDecl{
			Tok: token.IMPORT,
			Specs: []ast.Spec{
				&ast.ImportSpec{Path: &ast.BasicLit{Kind: token.STRING, Value: `"time"`}},
			},
		},
	}

	tagnamemap := map[string]string{}
	tagnamemap["ElemStreamDesc"] = "esds"

	splittagname := func(fnname string) (ok bool, tag, name string) {
		if len(fnname) > 5 && fnname[4] == '_' {
			tag = fnname[0:4]
			tag = strings.Replace(tag, "_", " ", 1)
			name = fnname[5:]
			ok = true
		} else {
			name = fnname
		}
		return
	}

	for _, decl := range file.Decls {
		if fndecl, ok := decl.(*ast.FuncDecl); ok {
			ok, tag, name := splittagname(fndecl.Name.Name)
			if ok {
				tagnamemap[name] = tag
			}
		}
	}

	tagfuncdecl := func(name, tag string) (decls ast.Decl) {
		return newdecl(name, "Tag", []*ast.Field{}, []*ast.Field{
			&ast.Field{Type: ast.NewIdent("Tag")},
		}, []ast.Stmt{
			&ast.ReturnStmt{
				Results: []ast.Expr{ast.NewIdent(strings.ToUpper(tag))}}})
	}

	for k, v := range tagnamemap {
		gen.Decls = append(gen.Decls, cc4decls(v)...)
		gen.Decls = append(gen.Decls, tagfuncdecl(k, v))
	}
	gen.Decls = append(gen.Decls, cc4decls("mdat")...)

	for _, decl := range file.Decls {
		if fndecl, ok := decl.(*ast.FuncDecl); ok {
			ok, tag, name := splittagname(fndecl.Name.Name)
			if ok {
				gen.Decls = append(gen.Decls, genatomdecl(fndecl, name, tag)...)
				gen.Decls = append(gen.Decls, getatommarshalfn(fndecl, name, tag, tagnamemap)...)
			} else {
				gen.Decls = append(gen.Decls, genatomdecl(fndecl, name, tag)...)
				gen.Decls = append(gen.Decls, getstructputgetlenfn(fndecl, name)...)
			}
		}
	}

	outfile, _ := os.Create(outfilename)
	printer.Fprint(outfile, fset, gen)
	outfile.Close()
}

func parse(filename, outfilename string) {
	fset := token.NewFileSet()
	file, err := parser.ParseFile(fset, filename, nil, 0)
	if err != nil {
		panic(err)
	}
	outfile, _ := os.Create(outfilename)
	ast.Fprint(outfile, fset, file, nil)
	outfile.Close()
}

func main() {
	switch os.Args[1] {
	case "parse":
		parse(os.Args[2], os.Args[3])

	case "gen":
		genatoms(os.Args[2], os.Args[3])
	}
}



================================================
FILE: format/mp4/mp4io/gen/pattern.go
================================================
package main

func moov_Movie() {
	atom(Header, MovieHeader)
	atom(MovieExtend, MovieExtend)
	atoms(Tracks, Track)
	_unknowns()
}

func mvhd_MovieHeader() {
	uint8(Version)
	uint24(Flags)
	time32(CreateTime)
	time32(ModifyTime)
	int32(TimeScale)
	int32(Duration)
	fixed32(PreferredRate)
	fixed16(PreferredVolume)
	_skip(10)
	array(Matrix, int32, 9)
	time32(PreviewTime)
	time32(PreviewDuration)
	time32(PosterTime)
	time32(SelectionTime)
	time32(SelectionDuration)
	time32(CurrentTime)
	int32(NextTrackId)
}

func trak_Track() {
	atom(Header, TrackHeader)
	atom(Media, Media)
	_unknowns()
}

func tkhd_TrackHeader() {
	uint8(Version)
	uint24(Flags)
	time32(CreateTime)
	time32(ModifyTime)
	int32(TrackId)
	_skip(4)
	int32(Duration)
	_skip(8)
	int16(Layer)
	int16(AlternateGroup)
	fixed16(Volume)
	_skip(2)
	array(Matrix, int32, 9)
	fixed32(TrackWidth)
	fixed32(TrackHeight)
}

func hdlr_HandlerRefer() {
	uint8(Version)
	uint24(Flags)
	bytes(Type, 4)
	bytes(SubType, 4)
	bytesleft(Name)
}

func mdia_Media() {
	atom(Header, MediaHeader)
	atom(Handler, HandlerRefer)
	atom(Info, MediaInfo)
	_unknowns()
}

func mdhd_MediaHeader() {
	uint8(Version)
	uint24(Flags)
	time32(CreateTime)
	time32(ModifyTime)
	int32(TimeScale)
	int32(Duration)
	int16(Language)
	int16(Quality)
}

func minf_MediaInfo() {
	atom(Sound, SoundMediaInfo)
	atom(Video, VideoMediaInfo)
	atom(Data, DataInfo)
	atom(Sample, SampleTable)
	_unknowns()
}

func dinf_DataInfo() {
	atom(Refer, DataRefer)
	_unknowns()
}

func dref_DataRefer() {
	uint8(Version)
	uint24(Flags)
	int32(_childrenNR)
	atom(Url, DataReferUrl)
}

func url__DataReferUrl() {
	uint8(Version)
	uint24(Flags)
}

func smhd_SoundMediaInfo() {
	uint8(Version)
	uint24(Flags)
	int16(Balance)
	_skip(2)
}

func vmhd_VideoMediaInfo() {
	uint8(Version)
	uint24(Flags)
	int16(GraphicsMode)
	array(Opcolor, int16, 3)
}

func stbl_SampleTable() {
	atom(SampleDesc, SampleDesc)
	atom(TimeToSample, TimeToSample)
	atom(CompositionOffset, CompositionOffset)
	atom(SampleToChunk, SampleToChunk)
	atom(SyncSample, SyncSample)
	atom(ChunkOffset, ChunkOffset)
	atom(SampleSize, SampleSize)
}

func stsd_SampleDesc() {
	uint8(Version)
	_skip(3)
	int32(_childrenNR)
	atom(AVC1Desc, AVC1Desc)
	atom(MP4ADesc, MP4ADesc)
	_unknowns()
}

func mp4a_MP4ADesc() {
	_skip(6)
	int16(DataRefIdx)
	int16(Version)
	int16(RevisionLevel)
	int32(Vendor)
	int16(NumberOfChannels)
	int16(SampleSize)
	int16(CompressionId)
	_skip(2)
	fixed32(SampleRate)
	atom(Conf, ElemStreamDesc)
	_unknowns()
}

func avc1_AVC1Desc() {
	_skip(6)
	int16(DataRefIdx)
	int16(Version)
	int16(Revision)
	int32(Vendor)
	int32(TemporalQuality)
	int32(SpatialQuality)
	int16(Width)
	int16(Height)
	fixed32(HorizontalResolution)
	fixed32(VorizontalResolution)
	_skip(4)
	int16(FrameCount)
	bytes(CompressorName, 32)
	int16(Depth)
	int16(ColorTableId)
	atom(Conf, AVC1Conf)
	_unknowns()
}

func avcC_AVC1Conf() {
	bytesleft(Data)
}

func stts_TimeToSample() {
	uint8(Version)
	uint24(Flags)
	uint32(_len_Entries)
	slice(Entries, TimeToSampleEntry)
}

func TimeToSampleEntry() {
	uint32(Count)
	uint32(Duration)
}

func stsc_SampleToChunk() {
	uint8(Version)
	uint24(Flags)
	uint32(_len_Entries)
	slice(Entries, SampleToChunkEntry)
}

func SampleToChunkEntry() {
	uint32(FirstChunk)
	uint32(SamplesPerChunk)
	uint32(SampleDescId)
}

func ctts_CompositionOffset() {
	uint8(Version)
	uint24(Flags)
	uint32(_len_Entries)
	slice(Entries, CompositionOffsetEntry)
}

func CompositionOffsetEntry() {
	uint32(Count)
	uint32(Offset)
}

func stss_SyncSample() {
	uint8(Version)
	uint24(Flags)
	uint32(_len_Entries)
	slice(Entries, uint32)
}

func stco_ChunkOffset() {
	uint8(Version)
	uint24(Flags)
	uint32(_len_Entries)
	slice(Entries, uint32)
}

func moof_MovieFrag() {
	atom(Header, MovieFragHeader)
	atoms(Tracks, TrackFrag)
	_unknowns()
}

func mfhd_MovieFragHeader() {
	uint8(Version)
	uint24(Flags)
	uint32(Seqnum)
}

func traf_TrackFrag() {
	atom(Header, TrackFragHeader)
	atom(DecodeTime, TrackFragDecodeTime)
	atom(Run, TrackFragRun)
	_unknowns()
}

func mvex_MovieExtend() {
	atoms(Tracks, TrackExtend)
	_unknowns()
}

func trex_TrackExtend() {
	uint8(Version)
	uint24(Flags)
	uint32(TrackId)
	uint32(DefaultSampleDescIdx)
	uint32(DefaultSampleDuration)
	uint32(DefaultSampleSize)
	uint32(DefaultSampleFlags)
}

func stsz_SampleSize() {
	uint8(Version)
	uint24(Flags)
	uint32(SampleSize)
	_code(func() {
		if self.SampleSize != 0 {
			return
		}
	})
	uint32(_len_Entries)
	slice(Entries, uint32)
}

func trun_TrackFragRun() {
	uint8(Version)
	uint24(Flags)
	uint32(_len_Entries)

	uint32(DataOffset, _code(func() {
		if self.Flags&TRUN_DATA_OFFSET != 0 {
			doit()
		}
	}))

	uint32(FirstSampleFlags, _code(func() {
		if self.Flags&TRUN_FIRST_SAMPLE_FLAGS != 0 {
			doit()
		}
	}))

	slice(Entries, TrackFragRunEntry, _code(func() {
		for i, entry := range self.Entries {
			var flags uint32
			if i > 0 {
				flags = self.Flags
			} else {
				flags = self.FirstSampleFlags
			}
			if flags&TRUN_SAMPLE_DURATION != 0 {
				pio.PutU32BE(b[n:], entry.Duration)
				n += 4
			}
			if flags&TRUN_SAMPLE_SIZE != 0 {
				pio.PutU32BE(b[n:], entry.Size)
				n += 4
			}
			if flags&TRUN_SAMPLE_FLAGS != 0 {
				pio.PutU32BE(b[n:], entry.Flags)
				n += 4
			}
			if flags&TRUN_SAMPLE_CTS != 0 {
				pio.PutU32BE(b[n:], entry.Cts)
				n += 4
			}
		}
	}, func() {
		for i := range self.Entries {
			var flags uint32
			if i > 0 {
				flags = self.Flags
			} else {
				flags = self.FirstSampleFlags
			}
			if flags&TRUN_SAMPLE_DURATION != 0 {
				n += 4
			}
			if flags&TRUN_SAMPLE_SIZE != 0 {
				n += 4
			}
			if flags&TRUN_SAMPLE_FLAGS != 0 {
				n += 4
			}
			if flags&TRUN_SAMPLE_CTS != 0 {
				n += 4
			}
		}
	}, func() {
		for i := 0; i < int(_len_Entries); i++ {
			var flags uint32
			if i > 0 {
				flags = self.Flags
			} else {
				flags = self.FirstSampleFlags
			}
			entry := &self.Entries[i]
			if flags&TRUN_SAMPLE_DURATION != 0 {
				entry.Duration = pio.U32BE(b[n:])
				n += 4
			}
			if flags&TRUN_SAMPLE_SIZE != 0 {
				entry.Size = pio.U32BE(b[n:])
				n += 4
			}
			if flags&TRUN_SAMPLE_FLAGS != 0 {
				entry.Flags = pio.U32BE(b[n:])
				n += 4
			}
			if flags&TRUN_SAMPLE_CTS != 0 {
				entry.Cts = pio.U32BE(b[n:])
				n += 4
			}
		}
	}))
}

func TrackFragRunEntry() {
	uint32(Duration)
	uint32(Size)
	uint32(Flags)
	uint32(Cts)
}

func tfhd_TrackFragHeader() {
	uint8(Version)
	uint24(Flags)

	uint64(BaseDataOffset, _code(func() {
		if self.Flags&TFHD_BASE_DATA_OFFSET != 0 {
			doit()
		}
	}))

	uint32(StsdId, _code(func() {
		if self.Flags&TFHD_STSD_ID != 0 {
			doit()
		}
	}))

	uint32(DefaultDuration, _code(func() {
		if self.Flags&TFHD_DEFAULT_DURATION != 0 {
			doit()
		}
	}))

	uint32(DefaultSize, _code(func() {
		if self.Flags&TFHD_DEFAULT_SIZE != 0 {
			doit()
		}
	}))

	uint32(DefaultFlags, _code(func() {
		if self.Flags&TFHD_DEFAULT_FLAGS != 0 {
			doit()
		}
	}))
}

func tfdt_TrackFragDecodeTime() {
	uint8(Version)
	uint24(Flags)
	time64(Time, _code(func() {
		if self.Version != 0 {
			PutTime64(b[n:], self.Time)
			n += 8
		} else {
			PutTime32(b[n:], self.Time)
			n += 4
		}
	}, func() {
		if self.Version != 0 {
			n += 8
		} else {
			n += 4
		}
	}, func() {
		if self.Version != 0 {
			self.Time = GetTime64(b[n:])
			n += 8
		} else {
			self.Time = GetTime32(b[n:])
			n += 4
		}
	}))
}



================================================
FILE: format/mp4/mp4io/mp4io.go
================================================

package mp4io

import (
	"github.com/nareix/joy4/utils/bits/pio"
	"os"
	"io"
	"fmt"
	"time"
	"math"
	"strings"
)

type ParseError struct {
	Debug string
	Offset int
	prev *ParseError
}

func (self *ParseError) Error() string {
	s := []string{}
	for p := self; p != nil; p = p.prev {
		s = append(s, fmt.Sprintf("%s:%d", p.Debug, p.Offset))
	}
	return "mp4io: parse error: "+strings.Join(s, ",")
}

func parseErr(debug string, offset int, prev error) (err error) {
	_prev, _ := prev.(*ParseError)
	return &ParseError{Debug: debug, Offset: offset, prev: _prev}
}

func GetTime32(b []byte) (t time.Time) {
	sec := pio.U32BE(b)
	t = time.Date(1904, time.January, 1, 0, 0, 0, 0, time.UTC)
	t = t.Add(time.Second*time.Duration(sec))
	return
}

func PutTime32(b []byte, t time.Time) {
	dur := t.Sub(time.Date(1904, time.January, 1, 0, 0, 0, 0, time.UTC))
	sec := uint32(dur/time.Second)
	pio.PutU32BE(b, sec)
}

func GetTime64(b []byte) (t time.Time) {
	sec := pio.U64BE(b)
	t = time.Date(1904, time.January, 1, 0, 0, 0, 0, time.UTC)
	t = t.Add(time.Second*time.Duration(sec))
	return
}

func PutTime64(b []byte, t time.Time) {
	dur := t.Sub(time.Date(1904, time.January, 1, 0, 0, 0, 0, time.UTC))
	sec := uint64(dur/time.Second)
	pio.PutU64BE(b, sec)
}

func PutFixed16(b []byte, f float64) {
	intpart, fracpart := math.Modf(f)
	b[0] = uint8(intpart)
	b[1] = uint8(fracpart*256.0)
}

func GetFixed16(b []byte) float64 {
	return float64(b[0])+float64(b[1])/256.0
}

func PutFixed32(b []byte, f float64) {
	intpart, fracpart := math.Modf(f)
	pio.PutU16BE(b[0:2], uint16(intpart))
	pio.PutU16BE(b[2:4], uint16(fracpart*65536.0))
}

func GetFixed32(b []byte) float64 {
	return float64(pio.U16BE(b[0:2]))+float64(pio.U16BE(b[2:4]))/65536.0
}

type Tag uint32

func (self Tag) String() string {
	var b [4]byte
	pio.PutU32BE(b[:], uint32(self))
	for i := 0; i < 4; i++ {
		if b[i] == 0 {
			b[i] = ' '
		}
	}
	return string(b[:])
}

type Atom interface{
	Pos() (int,int)
	Tag() Tag
	Marshal([]byte) int
	Unmarshal([]byte, int) (int,error)
	Len() int
	Children() []Atom
}

type AtomPos struct {
	Offset int
	Size int
}

func (self AtomPos) Pos() (int,int) {
	return self.Offset, self.Size
}

func (self *AtomPos) setPos(offset int, size int) {
	self.Offset, self.Size = offset, size
}

type Dummy struct {
	Data []byte
	Tag_ Tag
	AtomPos
}

func (self Dummy) Children() []Atom {
	return nil
}

func (self Dummy) Tag() Tag {
	return self.Tag_
}

func (self Dummy) Len() int {
	return len(self.Data)
}

func (self Dummy) Marshal(b []byte) int {
	copy(b, self.Data)
	return len(self.Data)
}

func (self *Dummy) Unmarshal(b []byte, offset int) (n int, err error) {
	(&self.AtomPos).setPos(offset, len(b))
	self.Data = b
	n = len(b)
	return
}

func StringToTag(tag string) Tag {
	var b [4]byte
	copy(b[:], []byte(tag))
	return Tag(pio.U32BE(b[:]))
}

func FindChildrenByName(root Atom, tag string) Atom {
	return FindChildren(root, StringToTag(tag))
}

func FindChildren(root Atom, tag Tag) Atom {
	if root.Tag() == tag {
		return root
	}
	for _, child := range root.Children() {
		if r := FindChildren(child, tag); r != nil {
			return r
		}
	}
	return nil
}

const (
	TFHD_BASE_DATA_OFFSET     = 0x01
	TFHD_STSD_ID              = 0x02
	TFHD_DEFAULT_DURATION     = 0x08
	TFHD_DEFAULT_SIZE         = 0x10
	TFHD_DEFAULT_FLAGS        = 0x20
	TFHD_DURATION_IS_EMPTY    = 0x010000
	TFHD_DEFAULT_BASE_IS_MOOF = 0x020000
)

const (
	TRUN_DATA_OFFSET        = 0x01
	TRUN_FIRST_SAMPLE_FLAGS = 0x04
	TRUN_SAMPLE_DURATION    = 0x100
	TRUN_SAMPLE_SIZE        = 0x200
	TRUN_SAMPLE_FLAGS       = 0x400
	TRUN_SAMPLE_CTS         = 0x800
)

const (
	MP4ESDescrTag          = 3
	MP4DecConfigDescrTag   = 4
	MP4DecSpecificDescrTag = 5
)

type ElemStreamDesc struct {
	DecConfig []byte
	TrackId uint16
	AtomPos
}

func (self ElemStreamDesc) Children() []Atom {
	return nil
}

func (self ElemStreamDesc) fillLength(b []byte, length int) (n int) {
	for i := 3; i > 0; i-- {
		b[n] = uint8(length>>uint(7*i))&0x7f|0x80
		n++
	}
	b[n] = uint8(length&0x7f)
	n++
	return
}

func (self ElemStreamDesc) lenDescHdr() (n int) {
	return 5
}

func (self ElemStreamDesc) fillDescHdr(b []byte, tag uint8, datalen int) (n int) {
	b[n] = tag
	n++
	n += self.fillLength(b[n:], datalen)
	return
}

func (self ElemStreamDesc) lenESDescHdr() (n int) {
	return self.lenDescHdr()+3
}

func (self ElemStreamDesc) fillESDescHdr(b []byte, datalen int) (n int) {
	n += self.fillDescHdr(b[n:], MP4ESDescrTag, datalen)
	pio.PutU16BE(b[n:], self.TrackId)
	n += 2
	b[n] = 0 // flags
	n++
	return
}

func (self ElemStreamDesc) lenDecConfigDescHdr() (n int) {
	return self.lenDescHdr()+2+3+4+4+self.lenDescHdr()
}

func (self ElemStreamDesc) fillDecConfigDescHdr(b []byte, datalen int) (n int) {
	n += self.fillDescHdr(b[n:], MP4DecConfigDescrTag, datalen)
	b[n] = 0x40 // objectid
	n++
	b[n] = 0x15 // streamtype
	n++
	// buffer size db
	pio.PutU24BE(b[n:], 0)
	n += 3
	// max bitrage
	pio.PutU32BE(b[n:], uint32(200000))
	n += 4
	// avg bitrage
	pio.PutU32BE(b[n:], uint32(0))
	n += 4
	n += self.fillDescHdr(b[n:], MP4DecSpecificDescrTag, datalen-n)
	return
}

func (self ElemStreamDesc) Len() (n int) {
	return 8+4+self.lenESDescHdr()+self.lenDecConfigDescHdr()+len(self.DecConfig)+self.lenDescHdr()+1
}

// Version(4)
// ESDesc(
//   MP4ESDescrTag
//   ESID(2)
//   ESFlags(1)
//   DecConfigDesc(
//     MP4DecConfigDescrTag
//     objectId streamType bufSize avgBitrate
//     DecSpecificDesc(
//       MP4DecSpecificDescrTag
//       decConfig
//     )
//   )
//   ?Desc(lenDescHdr+1)
// )

func (self ElemStreamDesc) Marshal(b []byte) (n int) {
	pio.PutU32BE(b[4:], uint32(ESDS))
	n += 8
	pio.PutU32BE(b[n:], 0) // Version
	n += 4
	datalen := self.Len()
	n += self.fillESDescHdr(b[n:], datalen-n-self.lenESDescHdr())
	n += self.fillDecConfigDescHdr(b[n:], datalen-n-self.lenDescHdr()-1)
	copy(b[n:], self.DecConfig)
	n += len(self.DecConfig)
	n += self.fillDescHdr(b[n:], 0x06, datalen-n-self.lenDescHdr())
	b[n] = 0x02
	n++
	pio.PutU32BE(b[0:], uint32(n))
	return
}

func (self *ElemStreamDesc) Unmarshal(b []byte, offset int) (n int, err error) {
	if len(b) < n+12 {
		err = parseErr("hdr", offset+n, err)
		return
	}
	(&self.AtomPos).setPos(offset, len(b))
	n += 8
	n += 4
	return self.parseDesc(b[n:], offset+n)
}

func (self *ElemStreamDesc) parseDesc(b []byte, offset int) (n int, err error) {
	var hdrlen int
	var datalen int
	var tag uint8
	if hdrlen, tag, datalen, err = self.parseDescHdr(b, offset); err != nil {
		return
	}
	n += hdrlen

	if len(b) < n+datalen {
		err = parseErr("datalen", offset+n, err)
		return
	}

	switch tag {
	case MP4ESDescrTag:
		if len(b) < n+3 {
			err = parseErr("MP4ESDescrTag", offset+n, err)
			return
		}
		if _, err = self.parseDesc(b[n+3:], offset+n+3); err != nil {
			return
		}

	case MP4DecConfigDescrTag:
		const size = 2+3+4+4
		if len(b) < n+size {
			err = parseErr("MP4DecSpecificDescrTag", offset+n, err)
			return
		}
		if _, err = self.parseDesc(b[n+size:], offset+n+size); err != nil {
			return
		}

	case MP4DecSpecificDescrTag:
		self.DecConfig = b[n:]
	}

	n += datalen
	return
}

func (self *ElemStreamDesc) parseLength(b []byte, offset int) (n int, length int, err error) {
	for n < 4 {
		if len(b) < n+1 {
			err = parseErr("len", offset+n, err)
			return
		}
		c := b[n]
		n++
		length = (length<<7)|(int(c)&0x7f)
		if c&0x80 == 0 {
			break
		}
	}
	return
}

func (self *ElemStreamDesc) parseDescHdr(b []byte, offset int) (n int, tag uint8, datalen int, err error) {
	if len(b) < n+1 {
		err = parseErr("tag", offset+n, err)
		return
	}
	tag = b[n]
	n++
	var lenlen int
	if lenlen, datalen, err = self.parseLength(b[n:], offset+n); err != nil {
		return
	}
	n += lenlen
	return
}

func ReadFileAtoms(r io.ReadSeeker) (atoms []Atom, err error) {
	for {
		offset, _ := r.Seek(0, 1)
		taghdr := make([]byte, 8)
		if _, err = io.ReadFull(r, taghdr); err != nil {
			if err == io.EOF {
				err = nil
			}
			return
		}
		size := pio.U32BE(taghdr[0:])
		tag := Tag(pio.U32BE(taghdr[4:]))

		var atom Atom
		switch tag {
		case MOOV:
			atom = &Movie{}
		case MOOF:
			atom = &MovieFrag{}
		}

		if atom != nil {
			b := make([]byte, int(size))
			if _, err = io.ReadFull(r, b[8:]); err != nil {
				return
			}
			copy(b, taghdr)
			if _, err = atom.Unmarshal(b, int(offset)); err != nil {
				return
			}
			atoms = append(atoms, atom)
		} else {
			dummy := &Dummy{Tag_: tag}
			dummy.setPos(int(offset), int(size))
			if _, err = r.Seek(int64(size)-8, 1); err != nil {
				return
			}
			atoms = append(atoms, dummy)
		}
	}
	return
}

func printatom(out io.Writer, root Atom, depth int) {
	offset, size := root.Pos()

	type stringintf interface {
		String() string
	}

	fmt.Fprintf(out,
		"%s%s offset=%d size=%d",
		strings.Repeat(" ", depth*2), root.Tag(), offset, size,
	)
	if str, ok := root.(stringintf); ok {
		fmt.Fprint(out, " ", str.String())
	}
	fmt.Fprintln(out)

	children := root.Children()
	for _, child := range children {
		printatom(out, child, depth+1)
	}
}

func FprintAtom(out io.Writer, root Atom) {
	printatom(out, root, 0)
}

func PrintAtom(root Atom) {
	FprintAtom(os.Stdout, root)
}

func (self MovieHeader) String() string {
	return fmt.Sprintf("dur=%d", self.Duration)
}

func (self TimeToSample) String() string {
	return fmt.Sprintf("entries=%d", len(self.Entries))
}

func (self SampleToChunk) String() string {
	return fmt.Sprintf("entries=%d", len(self.Entries))
}

func (self SampleSize) String() string {
	return fmt.Sprintf("entries=%d", len(self.Entries))
}

func (self SyncSample) String() string {
	return fmt.Sprintf("entries=%d", len(self.Entries))
}

func (self CompositionOffset) String() string {
	return fmt.Sprintf("entries=%d", len(self.Entries))
}

func (self ChunkOffset) String() string {
	return fmt.Sprintf("entries=%d", len(self.Entries))
}

func (self TrackFragRun) String() string {
	return fmt.Sprintf("dataoffset=%d", self.DataOffset)
}

func (self TrackFragHeader) String() string {
	return fmt.Sprintf("basedataoffset=%d", self.BaseDataOffset)
}

func (self ElemStreamDesc) String() string {
	return fmt.Sprintf("configlen=%d", len(self.DecConfig))
}

func (self *Track) GetAVC1Conf() (conf *AVC1Conf) {
	atom := FindChildren(self, AVCC)
	conf, _ = atom.(*AVC1Conf)
	return
}

func (self *Track) GetElemStreamDesc() (esds *ElemStreamDesc) {
	atom := FindChildren(self, ESDS)
	esds, _ = atom.(*ElemStreamDesc)
	return
}



================================================
FILE: format/mp4/muxer.go
================================================
package mp4

import (
	"fmt"
	"time"
	"github.com/nareix/joy4/av"
	"github.com/nareix/joy4/codec/aacparser"
	"github.com/nareix/joy4/codec/h264parser"
	"github.com/nareix/joy4/format/mp4/mp4io"
	"github.com/nareix/joy4/utils/bits/pio"
	"io"
	"bufio"
)

type Muxer struct {
	w          io.WriteSeeker
	bufw       *bufio.Writer
	wpos       int64
	streams    []*Stream
}

func NewMuxer(w io.WriteSeeker) *Muxer {
	return &Muxer{
		w: w,
		bufw: bufio.NewWriterSize(w, pio.RecommendBufioSize),
	}
}

func (self *Muxer) newStream(codec av.CodecData) (err error) {
	switch codec.Type() {
	case av.H264, av.AAC:

	default:
		err = fmt.Errorf("mp4: codec type=%v is not supported", codec.Type())
		return
	}
	stream := &Stream{CodecData: codec}

	stream.sample = &mp4io.SampleTable{
		SampleDesc:   &mp4io.SampleDesc{},
		TimeToSample: &mp4io.TimeToSample{},
		SampleToChunk: &mp4io.SampleToChunk{
			Entries: []mp4io.SampleToChunkEntry{
				{
					FirstChunk:      1,
					SampleDescId:    1,
					SamplesPerChunk: 1,
				},
			},
		},
		SampleSize:  &mp4io.SampleSize{},
		ChunkOffset: &mp4io.ChunkOffset{},
	}

	stream.trackAtom = &mp4io.Track{
		Header: &mp4io.TrackHeader{
			TrackId:  int32(len(self.streams)+1),
			Flags:    0x0003, // Track enabled | Track in movie
			Duration: 0,      // fill later
			Matrix:   [9]int32{0x10000, 0, 0, 0, 0x10000, 0, 0, 0, 0x40000000},
		},
		Media: &mp4io.Media{
			Header: &mp4io.MediaHeader{
				TimeScale: 0, // fill later
				Duration:  0, // fill later
				Language:  21956,
			},
			Info: &mp4io.MediaInfo{
				Sample: stream.sample,
				Data: &mp4io.DataInfo{
					Refer: &mp4io.DataRefer{
						Url: &mp4io.DataReferUrl{
							Flags: 0x000001, // Self reference
						},
					},
				},
			},
		},
	}

	switch codec.Type() {
	case av.H264:
		stream.sample.SyncSample = &mp4io.SyncSample{}
	}

	stream.timeScale = 90000
	stream.muxer = self
	self.streams = append(self.streams, stream)

	return
}

func (self *Stream) fillTrackAtom() (err error) {
	self.trackAtom.Media.Header.TimeScale = int32(self.timeScale)
	self.trackAtom.Media.Header.Duration = int32(self.duration)

	if self.Type() == av.H264 {
		codec := self.CodecData.(h264parser.CodecData)
		width, height := codec.Width(), codec.Height()
		self.sample.SampleDesc.AVC1Desc = &mp4io.AVC1Desc{
			DataRefIdx:           1,
			HorizontalResolution: 72,
			VorizontalResolution: 72,
			Width:                int16(width),
			Height:               int16(height),
			FrameCount:           1,
			Depth:                24,
			ColorTableId:         -1,
			Conf:                 &mp4io.AVC1Conf{Data: codec.AVCDecoderConfRecordBytes()},
		}
		self.trackAtom.Media.Handler = &mp4io.HandlerRefer{
			SubType: [4]byte{'v','i','d','e'},
			Name:    []byte("Video Media Handler"),
		}
		self.trackAtom.Media.Info.Video = &mp4io.VideoMediaInfo{
			Flags: 0x000001,
		}
		self.trackAtom.Header.TrackWidth = float64(width)
		self.trackAtom.Header.TrackHeight = float64(height)

	} else if self.Type() == av.AAC {
		codec := self.CodecData.(aacparser.CodecData)
		self.sample.SampleDesc.MP4ADesc = &mp4io.MP4ADesc{
			DataRefIdx:       1,
			NumberOfChannels: int16(codec.ChannelLayout().Count()),
			SampleSize:       int16(codec.SampleFormat().BytesPerSample()),
			SampleRate:       float64(codec.SampleRate()),
			Conf: &mp4io.ElemStreamDesc{
				DecConfig: codec.MPEG4AudioConfigBytes(),
			},
		}
		self.trackAtom.Header.Volume = 1
		self.trackAtom.Header.AlternateGroup = 1
		self.trackAtom.Media.Handler = &mp4io.HandlerRefer{
			SubType: [4]byte{'s','o','u','n'},
			Name:    []byte("Sound Handler"),
		}
		self.trackAtom.Media.Info.Sound = &mp4io.SoundMediaInfo{}

	} else {
		err = fmt.Errorf("mp4: codec type=%d invalid", self.Type())
	}

	return
}

func (self *Muxer) WriteHeader(streams []av.CodecData) (err error) {
	self.streams = []*Stream{}
	for _, stream := range streams {
		if err = self.newStream(stream); err != nil {
			return
		}
	}

	taghdr := make([]byte, 8)
	pio.PutU32BE(taghdr[4:], uint32(mp4io.MDAT))
	if _, err = self.w.Write(taghdr); err != nil {
		return
	}
	self.wpos += 8

	for _, stream := range self.streams {
		if stream.Type().IsVideo() {
			stream.sample.CompositionOffset = &mp4io.CompositionOffset{}
		}
	}
	return
}

func (self *Muxer) WritePacket(pkt av.Packet) (err error) {
	stream := self.streams[pkt.Idx]
	if stream.lastpkt != nil {
		if err = stream.writePacket(*stream.lastpkt, pkt.Time-stream.lastpkt.Time); err != nil {
			return
		}
	}
	stream.lastpkt = &pkt
	return
}

func (self *Stream) writePacket(pkt av.Packet, rawdur time.Duration) (err error) {
	if rawdur < 0 {
		err = fmt.Errorf("mp4: stream#%d time=%v < lasttime=%v", pkt.Idx, pkt.Time, self.lastpkt.Time)
		return
	}

	if _, err = self.muxer.bufw.Write(pkt.Data); err != nil {
		return
	}

	if pkt.IsKeyFrame && self.sample.SyncSample != nil {
		self.sample.SyncSample.Entries = append(self.sample.SyncSample.Entries, uint32(self.sampleIndex+1))
	}

	duration := uint32(self.timeToTs(rawdur))
	if self.sttsEntry == nil || duration != self.sttsEntry.Duration {
		self.sample.TimeToSample.Entries = append(self.sample.TimeToSample.Entries, mp4io.TimeToSampleEntry{Duration: duration})
		self.sttsEntry = &self.sample.TimeToSample.Entries[len(self.sample.TimeToSample.Entries)-1]
	}
	self.sttsEntry.Count++

	if self.sample.CompositionOffset != nil {
		offset := uint32(self.timeToTs(pkt.CompositionTime))
		if self.cttsEntry == nil || offset != self.cttsEntry.Offset {
			table := self.sample.CompositionOffset
			table.Entries = append(table.Entries, mp4io.CompositionOffsetEntry{Offset: offset})
			self.cttsEntry = &table.Entries[len(table.Entries)-1]
		}
		self.cttsEntry.Count++
	}

	self.duration += int64(duration)
	self.sampleIndex++
	self.sample.ChunkOffset.Entries = append(self.sample.ChunkOffset.Entries, uint32(self.muxer.wpos))
	self.sample.SampleSize.Entries = append(self.sample.SampleSize.Entries, uint32(len(pkt.Data)))

	self.muxer.wpos += int64(len(pkt.Data))
	return
}

func (self *Muxer) WriteTrailer() (err error) {
	for _, stream := range self.streams {
		if stream.lastpkt != nil {
			if err = stream.writePacket(*stream.lastpkt, 0); err != nil {
				return
			}
			stream.lastpkt = nil
		}
	}

	moov := &mp4io.Movie{}
	moov.Header = &mp4io.MovieHeader{
		PreferredRate:   1,
		PreferredVolume: 1,
		Matrix:          [9]int32{0x10000, 0, 0, 0, 0x10000, 0, 0, 0, 0x40000000},
		NextTrackId:     2,
	}

	maxDur := time.Duration(0)
	timeScale := int64(10000)
	for _, stream := range self.streams {
		if err = stream.fillTrackAtom(); err != nil {
			return
		}
		dur := stream.tsToTime(stream.duration)
		stream.trackAtom.Header.Duration = int32(timeToTs(dur, timeScale))
		if dur > maxDur {
			maxDur = dur
		}
		moov.Tracks = append(moov.Tracks, stream.trackAtom)
	}
	moov.Header.TimeScale = int32(timeScale)
	moov.Header.Duration = int32(timeToTs(maxDur, timeScale))

	if err = self.bufw.Flush(); err != nil {
		return
	}

	var mdatsize int64
	if mdatsize, err = self.w.Seek(0, 1); err != nil {
		return
	}
	if _, err = self.w.Seek(0, 0); err != nil {
		return
	}
	taghdr := make([]byte, 4)
	pio.PutU32BE(taghdr, uint32(mdatsize))
	if _, err = self.w.Write(taghdr); err != nil {
		return
	}

	if _, err = self.w.Seek(0, 2); err != nil {
		return
	}
	b := make([]byte, moov.Len())
	moov.Marshal(b)
	if _, err = self.w.Write(b); err != nil {
		return
	}

	return
}


================================================
FILE: format/mp4/stream.go
================================================
package mp4

import (
	"github.com/nareix/joy4/av"
	"github.com/nareix/joy4/format/mp4/mp4io"
	"time"
)

type Stream struct {
	av.CodecData

	trackAtom *mp4io.Track
	idx       int

	lastpkt *av.Packet

	timeScale int64
	duration  int64

	muxer *Muxer
	demuxer *Demuxer

	sample      *mp4io.SampleTable
	sampleIndex int

	sampleOffsetInChunk int64
	syncSampleIndex     int

	dts                    int64
	sttsEntryIndex         int
	sampleIndexInSttsEntry int

	cttsEntryIndex         int
	sampleIndexInCttsEntry int

	chunkGroupIndex    int
	chunkIndex         int
	sampleIndexInChunk int

	sttsEntry *mp4io.TimeToSampleEntry
	cttsEntry *mp4io.CompositionOffsetEntry
}

func timeToTs(tm time.Duration, timeScale int64) int64 {
	return int64(tm*time.Duration(timeScale) / time.Second)
}

func tsToTime(ts int64, timeScale int64) time.Duration {
	return time.Duration(ts)*time.Second / time.Duration(timeScale)
}

func (self *Stream) timeToTs(tm time.Duration) int64 {
	return int64(tm*time.Duration(self.timeScale) / time.Second)
}

func (self *Stream) tsToTime(ts int64) time.Duration {
	return time.Duration(ts)*time.Second / time.Duration(self.timeScale)
}


================================================
FILE: format/rtmp/rtmp.go
================================================
package rtmp

import (
	"bufio"
	"bytes"
	"crypto/hmac"
	"crypto/rand"
	"crypto/sha256"
	"encoding/hex"
	"fmt"
	"github.com/nareix/joy4/utils/bits/pio"
	"github.com/nareix/joy4/av"
	"github.com/nareix/joy4/av/avutil"
	"github.com/nareix/joy4/format/flv"
	"github.com/nareix/joy4/format/flv/flvio"
	"io"
	"net"
	"net/url"
	"strings"
	"time"
)

var Debug bool

func ParseURL(uri string) (u *url.URL, err error) {
	if u, err = url.Parse(uri); err != nil {
		return
	}
	if _, _, serr := net.SplitHostPort(u.Host); serr != nil {
		u.Host += ":1935"
	}
	return
}

func Dial(uri string) (conn *Conn, err error) {
	return DialTimeout(uri, 0)
}

func DialTimeout(uri string, timeout time.Duration) (conn *Conn, err error) {
	var u *url.URL
	if u, err = ParseURL(uri); err != nil {
		return
	}

	dailer := net.Dialer{Timeout: timeout}
	var netconn net.Conn
	if netconn, err = dailer.Dial("tcp", u.Host); err != nil {
		return
	}

	conn = NewConn(netconn)
	conn.URL = u
	return
}

type Server struct {
	Addr          string
	HandlePublish func(*Conn)
	HandlePlay    func(*Conn)
	HandleConn    func(*Conn)
}

func (self *Server) handleConn(conn *Conn) (err error) {
	if self.HandleConn != nil {
		self.HandleConn(conn)
	} else {
		if err = conn.prepare(stageCommandDone, 0); err != nil {
			return
		}

		if conn.playing {
			if self.HandlePlay != nil {
				self.HandlePlay(conn)
			}
		} else if conn.publishing {
			if self.HandlePublish != nil {
				self.HandlePublish(conn)
			}
		}
	}

	return
}

func (self *Server) ListenAndServe() (err error) {
	addr := self.Addr
	if addr == "" {
		addr = ":1935"
	}
	var tcpaddr *net.TCPAddr
	if tcpaddr, err = net.ResolveTCPAddr("tcp", addr); err != nil {
		err = fmt.Errorf("rtmp: ListenAndServe: %s", err)
		return
	}

	var listener *net.TCPListener
	if listener, err = net.ListenTCP("tcp", tcpaddr); err != nil {
		return
	}

	if Debug {
		fmt.Println("rtmp: server: listening on", addr)
	}

	for {
		var netconn net.Conn
		if netconn, err = listener.Accept(); err != nil {
			return
		}

		if Debug {
			fmt.Println("rtmp: server: accepted")
		}

		conn := NewConn(netconn)
		conn.isserver = true
		go func() {
			err := self.handleConn(conn)
			if Debug {
				fmt.Println("rtmp: server: client closed err:", err)
			}
		}()
	}
}

const (
	stageHandshakeDone = iota + 1
	stageCommandDone
	stageCodecDataDone
)

const (
	prepareReading = iota + 1
	prepareWriting
)

type Conn struct {
	URL             *url.URL
	OnPlayOrPublish func(string, flvio.AMFMap) error

	prober  *flv.Prober
	streams []av.CodecData

	txbytes uint64
	rxbytes uint64

	bufr *bufio.Reader
	bufw *bufio.Writer
	ackn uint32

	writebuf []byte
	readbuf  []byte

	netconn   net.Conn
	txrxcount *txrxcount

	writeMaxChunkSize int
	readMaxChunkSize  int
	readAckSize       uint32
	readcsmap         map[uint32]*chunkStream

	isserver            bool
	publishing, playing bool
	reading, writing    bool
	stage               int

	avmsgsid uint32

	gotcommand     bool
	commandname    string
	commandtransid float64
	commandobj     flvio.AMFMap
	commandparams  []interface{}

	gotmsg      bool
	timestamp   uint32
	msgdata     []byte
	msgtypeid   uint8
	datamsgvals []interface{}
	avtag       flvio.Tag

	eventtype uint16
}

type txrxcount struct {
	io.ReadWriter
	txbytes uint64
	rxbytes uint64
}

func (self *txrxcount) Read(p []byte) (int, error) {
	n, err := self.ReadWriter.Read(p)
	self.rxbytes += uint64(n)
	return n, err
}

func (self *txrxcount) Write(p []byte) (int, error) {
	n, err := self.ReadWriter.Write(p)
	self.txbytes += uint64(n)
	return n, err
}

func NewConn(netconn net.Conn) *Conn {
	conn := &Conn{}
	conn.prober = &flv.Prober{}
	conn.netconn = netconn
	conn.readcsmap = make(map[uint32]*chunkStream)
	conn.readMaxChunkSize = 128
	conn.writeMaxChunkSize = 128
	conn.bufr = bufio.NewReaderSize(netconn, pio.RecommendBufioSize)
	conn.bufw = bufio.NewWriterSize(netconn, pio.RecommendBufioSize)
	conn.txrxcount = &txrxcount{ReadWriter: netconn}
	conn.writebuf = make([]byte, 4096)
	conn.readbuf = make([]byte, 4096)
	return conn
}

type chunkStream struct {
	timenow     uint32
	timedelta   uint32
	hastimeext  bool
	msgsid      uint32
	msgtypeid   uint8
	msgdatalen  uint32
	msgdataleft uint32
	msghdrtype  uint8
	msgdata     []byte
}

func (self *chunkStream) Start() {
	self.msgdataleft = self.msgdatalen
	self.msgdata = make([]byte, self.msgdatalen)
}

const (
	msgtypeidUserControl      = 4
	msgtypeidAck              = 3
	msgtypeidWindowAckSize    = 5
	msgtypeidSetPeerBandwidth = 6
	msgtypeidSetChunkSize     = 1
	msgtypeidCommandMsgAMF0   = 20
	msgtypeidCommandMsgAMF3   = 17
	msgtypeidDataMsgAMF0      = 18
	msgtypeidDataMsgAMF3      = 15
	msgtypeidVideoMsg         = 9
	msgtypeidAudioMsg         = 8
)

const (
	eventtypeStreamBegin      = 0
	eventtypeSetBufferLength  = 3
	eventtypeStreamIsRecorded = 4
)

func (self *Conn) NetConn() net.Conn {
	return self.netconn
}

func (self *Conn) TxBytes() uint64 {
	return self.txrxcount.txbytes
}

func (self *Conn) RxBytes() uint64 {
	return self.txrxcount.rxbytes
}

func (self *Conn) Close() (err error) {
	return self.netconn.Close()
}

func (self *Conn) pollCommand() (err error) {
	for {
		if err = self.pollMsg(); err != nil {
			return
		}
		if self.gotcommand {
			return
		}
	}
}

func (self *Conn) pollAVTag() (tag flvio.Tag, err error) {
	for {
		if err = self.pollMsg(); err != nil {
			return
		}
		switch self.msgtypeid {
		case msgtypeidVideoMsg, msgtypeidAudioMsg:
			tag = self.avtag
			return
		}
	}
}

func (self *Conn) pollMsg() (err error) {
	self.gotmsg = false
	self.gotcommand = false
	self.datamsgvals = nil
	self.avtag = flvio.Tag{}
	for {
		if err = self.readChunk(); err != nil {
			return
		}
		if self.gotmsg {
			return
		}
	}
}

func SplitPath(u *url.URL) (app, stream string) {
	pathsegs := strings.SplitN(u.RequestURI(), "/", 3)
	if len(pathsegs) > 1 {
		app = pathsegs[1]
	}
	if len(pathsegs) > 2 {
		stream = pathsegs[2]
	}
	return
}

func getTcUrl(u *url.URL) string {
	app, _ := SplitPath(u)
	nu := *u
	nu.Path = "/" + app
	return nu.String()
}

func createURL(tcurl, app, play string) (u *url.URL) {
	ps := strings.Split(app+"/"+play, "/")
	out := []string{""}
	for _, s := range ps {
		if len(s) > 0 {
			out = append(out, s)
		}
	}
	if len(out) < 2 {
		out = append(out, "")
	}
	path := strings.Join(out, "/")
	u, _ = url.ParseRequestURI(path)

	if tcurl != "" {
		tu, _ := url.Parse(tcurl)
		if tu != nil {
			u.Host = tu.Host
			u.Scheme = tu.Scheme
		}
	}
	return
}

var CodecTypes = flv.CodecTypes

func (self *Conn) writeBasicConf() (err error) {
	// > SetChunkSize
	if err = self.writeSetChunkSize(1024 * 1024 * 128); err != nil {
		return
	}
	// > WindowAckSize
	if err = self.writeWindowAckSize(5000000); err != nil {
		return
	}
	// > SetPeerBandwidth
	if err = self.writeSetPeerBandwidth(5000000, 2); err != nil {
		return
	}
	return
}

func (self *Conn) readConnect() (err error) {
	var connectpath string

	// < connect("app")
	if err = self.pollCommand(); err != nil {
		return
	}
	if self.commandname != "connect" {
		err = fmt.Errorf("rtmp: first command is not connect")
		return
	}
	if self.commandobj == nil {
		err = fmt.Errorf("rtmp: connect command params invalid")
		return
	}

	var ok bool
	var _app, _tcurl interface{}
	if _app, ok = self.commandobj["app"]; !ok {
		err = fmt.Errorf("rtmp: `connect` params missing `app`")
		return
	}
	connectpath, _ = _app.(string)

	var tcurl string
	if _tcurl, ok = self.commandobj["tcUrl"]; !ok {
		_tcurl, ok = self.commandobj["tcurl"]
	}
	if ok {
		tcurl, _ = _tcurl.(string)
	}
	connectparams := self.commandobj

	if err = self.writeBasicConf(); err != nil {
		return
	}

	// > _result("NetConnection.Connect.Success")
	if err = self.writeCommandMsg(3, 0, "_result", self.commandtransid,
		flvio.AMFMap{
			"fmtVer":       "FMS/3,0,1,123",
			"capabilities": 31,
		},
		flvio.AMFMap{
			"level":          "status",
			"code":           "NetConnection.Connect.Success",
			"description":    "Connection succeeded.",
			"objectEncoding": 3,
		},
	); err != nil {
		return
	}

	if err = self.flushWrite(); err != nil {
		return
	}

	for {
		if err = self.pollMsg(); err != nil {
			return
		}
		if self.gotcommand {
			switch self.commandname {

			// < createStream
			case "createStream":
				self.avmsgsid = uint32(1)
				// > _result(streamid)
				if err = self.writeCommandMsg(3, 0, "_result", self.commandtransid, nil, self.avmsgsid); err != nil {
					return
				}
				if err = self.flushWrite(); err != nil {
					return
				}

			// < publish("path")
			case "publish":
				if Debug {
					fmt.Println("rtmp: < publish")
				}

				if len(self.commandparams) < 1 {
					err = fmt.Errorf("rtmp: publish params invalid")
					return
				}
				publishpath, _ := self.commandparams[0].(string)

				var cberr error
				if self.OnPlayOrPublish != nil {
					cberr = self.OnPlayOrPublish(self.commandname, connectparams)
				}

				// > onStatus()
				if err = self.writeCommandMsg(5, self.avmsgsid,
					"onStatus", self.commandtransid, nil,
					flvio.AMFMap{
						"level":       "status",
						"code":        "NetStream.Publish.Start",
						"description": "Start publishing",
					},
				); err != nil {
					return
				}
				if err = self.flushWrite(); err != nil {
					return
				}

				if cberr != nil {
					err = fmt.Errorf("rtmp: OnPlayOrPublish check failed")
					return
				}

				self.URL = createURL(tcurl, connectpath, publishpath)
				self.publishing = true
				self.reading = true
				self.stage++
				return

			// < play("path")
			case "play":
				if Debug {
					fmt.Println("rtmp: < play")
				}

				if len(self.commandparams) < 1 {
					err = fmt.Errorf("rtmp: command play params invalid")
					return
				}
				playpath, _ := self.commandparams[0].(string)

				// > streamBegin(streamid)
				if err = self.writeStreamBegin(self.avmsgsid); err != nil {
					return
				}

				// > onStatus()
				if err = self.writeCommandMsg(5, self.avmsgsid,
					"onStatus", self.commandtransid, nil,
					flvio.AMFMap{
						"level":       "status",
						"code":        "NetStream.Play.Start",
						"description": "Start live",
					},
				); err != nil {
					return
				}

				// > |RtmpSampleAccess()
				if err = self.writeDataMsg(5, self.avmsgsid,
					"|RtmpSampleAccess", true, true,
				); err != nil {
					return
				}

				if err = self.flushWrite(); err != nil {
					return
				}

				self.URL = createURL(tcurl, connectpath, playpath)
				self.playing = true
				self.writing = true
				self.stage++
				return
			}

		}
	}

	return
}

func (self *Conn) checkConnectResult() (ok bool, errmsg string) {
	if len(self.commandparams) < 1 {
		errmsg = "params length < 1"
		return
	}

	obj, _ := self.commandparams[0].(flvio.AMFMap)
	if obj == nil {
		errmsg = "params[0] not object"
		return
	}

	_code, _ := obj["code"]
	if _code == nil {
		errmsg = "code invalid"
		return
	}

	code, _ := _code.(string)
	if code != "NetConnection.Connect.Success" {
		errmsg = "code != NetConnection.Connect.Success"
		return
	}

	ok = true
	return
}

func (self *Conn) checkCreateStreamResult() (ok bool, avmsgsid uint32) {
	if len(self.commandparams) < 1 {
		return
	}

	ok = true
	_avmsgsid, _ := self.commandparams[0].(float64)
	avmsgsid = uint32(_avmsgsid)
	return
}

func (self *Conn) probe() (err error) {
	for !self.prober.Probed() {
		var tag flvio.Tag
		if tag, err = self.pollAVTag(); err != nil {
			return
		}
		if err = self.prober.PushTag(tag, int32(self.timestamp)); err != nil {
			return
		}
	}

	self.streams = self.prober.Streams
	self.stage++
	return
}

func (self *Conn) writeConnect(path string) (err error) {
	if err = self.writeBasicConf(); err != nil {
		return
	}

	// > connect("app")
	if Debug {
		fmt.Printf("rtmp: > connect('%s') host=%s\n", path, self.URL.Host)
	}
	if err = self.writeCommandMsg(3, 0, "connect", 1,
		flvio.AMFMap{
			"app":           path,
			"flashVer":      "MAC 22,0,0,192",
			"tcUrl":         getTcUrl(self.URL),
			"fpad":          false,
			"capabilities":  15,
			"audioCodecs":   4071,
			"videoCodecs":   252,
			"videoFunction": 1,
		},
	); err != nil {
		return
	}

	if err = self.flushWrite(); err != nil {
		return
	}

	for {
		if err = self.pollMsg(); err != nil {
			return
		}
		if self.gotcommand {
			// < _result("NetConnection.Connect.Success")
			if self.commandname == "_result" {
				var ok bool
				var errmsg string
				if ok, errmsg = self.checkConnectResult(); !ok {
					err = fmt.Errorf("rtmp: command connect failed: %s", errmsg)
					return
				}
				if Debug {
					fmt.Printf("rtmp: < _result() of connect\n")
				}
				break
			}
		} else {
			if self.msgtypeid == msgtypeidWindowAckSize {
				if len(self.msgdata) == 4 {
					self.readAckSize = pio.U32BE(self.msgdata)
				}
				if err = self.writeWindowAckSize(0xffffffff); err != nil {
					return
				}
			}
		}
	}

	return
}

func (self *Conn) connectPublish() (err error) {
	connectpath, publishpath := SplitPath(self.URL)

	if err = self.writeConnect(connectpath); err != nil {
		return
	}

	transid := 2

	// > createStream()
	if Debug {
		fmt.Printf("rtmp: > createStream()\n")
	}
	if err = self.writeCommandMsg(3, 0, "createStream", transid, nil); err != nil {
		return
	}
	transid++

	if err = self.flushWrite(); err != nil {
		return
	}

	for {
		if err = self.pollMsg(); err != nil {
			return
		}
		if self.gotcommand {
			// < _result(avmsgsid) of createStream
			if self.commandname == "_result" {
				var ok bool
				if ok, self.avmsgsid = self.checkCreateStreamResult(); !ok {
					err = fmt.Errorf("rtmp: createStream command failed")
					return
				}
				break
			}
		}
	}

	// > publish('app')
	if Debug {
		fmt.Printf("rtmp: > publish('%s')\n", publishpath)
	}
	if err = self.writeCommandMsg(8, self.avmsgsid, "publish", transid, nil, publishpath); err != nil {
		return
	}
	transid++

	if err = self.flushWrite(); err != nil {
		return
	}

	self.writing = true
	self.publishing = true
	self.stage++
	return
}

func (self *Conn) connectPlay() (err error) {
	connectpath, playpath := SplitPath(self.URL)

	if err = self.writeConnect(connectpath); err != nil {
		return
	}

	// > createStream()
	if Debug {
		fmt.Printf("rtmp: > createStream()\n")
	}
	if err = self.writeCommandMsg(3, 0, "createStream", 2, nil); err != nil {
		return
	}

	// > SetBufferLength 0,100ms
	if err = self.writeSetBufferLength(0, 100); err != nil {
		return
	}

	if err = self.flushWrite(); err != nil {
		return
	}

	for {
		if err = self.pollMsg(); err != nil {
			return
		}
		if self.gotcommand {
			// < _result(avmsgsid) of createStream
			if self.commandname == "_result" {
				var ok bool
				if ok, self.avmsgsid = self.checkCreateStreamResult(); !ok {
					err = fmt.Errorf("rtmp: createStream command failed")
					return
				}
				break
			}
		}
	}

	// > play('app')
	if Debug {
		fmt.Printf("rtmp: > play('%s')\n", playpath)
	}
	if err = self.writeCommandMsg(8, self.avmsgsid, "play", 0, nil, playpath); err != nil {
		return
	}
	if err = self.flushWrite(); err != nil {
		return
	}

	self.reading = true
	self.playing = true
	self.stage++
	return
}

func (self *Conn) ReadPacket() (pkt av.Packet, err error) {
	if err = self.prepare(stageCodecDataDone, prepareReading); err != nil {
		return
	}

	if !self.prober.Empty() {
		pkt = self.prober.PopPacket()
		return
	}

	for {
		var tag flvio.Tag
		if tag, err = self.pollAVTag(); err != nil {
			return
		}

		var ok bool
		if pkt, ok = self.prober.TagToPacket(tag, int32(self.timestamp)); ok {
			return
		}
	}

	return
}

func (self *Conn) Prepare() (err error) {
	return self.prepare(stageCommandDone, 0)
}

func (self *Conn) prepare(stage int, flags int) (err error) {
	for self.stage < stage {
		switch self.stage {
		case 0:
			if self.isserver {
				if err = self.handshakeServer(); err != nil {
					return
				}
			} else {
				if err = self.handshakeClient(); err != nil {
					return
				}
			}

		case stageHandshakeDone:
			if self.isserver {
				if err = self.readConnect(); err != nil {
					return
				}
			} else {
				if flags == prepareReading {
					if err = self.connectPlay(); err != nil {
						return
					}
				} else {
					if err = self.connectPublish(); err != nil {
						return
					}
				}
			}

		case stageCommandDone:
			if flags == prepareReading {
				if err = self.probe(); err != nil {
					return
				}
			} else {
				err = fmt.Errorf("rtmp: call WriteHeader() before WritePacket()")
				return
			}
		}
	}
	return
}

func (self *Conn) Streams() (streams []av.CodecData, err error) {
	if err = self.prepare(stageCodecDataDone, prepareReading); err != nil {
		return
	}
	streams = self.streams
	return
}

func (self *Conn) WritePacket(pkt av.Packet) (err error) {
	if err = self.prepare(stageCodecDataDone, prepareWriting); err != nil {
		return
	}

	stream := self.streams[pkt.Idx]
	tag, timestamp := flv.PacketToTag(pkt, stream)

	if Debug {
		fmt.Println("rtmp: WritePacket", pkt.Idx, pkt.Time, pkt.CompositionTime)
	}

	if err = self.writeAVTag(tag, int32(timestamp)); err != nil {
		return
	}

	return
}

func (self *Conn) WriteTrailer() (err error) {
	if err = self.flushWrite(); err != nil {
		return
	}
	return
}

func (self *Conn) WriteHeader(streams []av.CodecData) (err error) {
	if err = self.prepare(stageCommandDone, prepareWriting); err != nil {
		return
	}

	var metadata flvio.AMFMap
	if metadata, err = flv.NewMetadataByStreams(streams); err != nil {
		return
	}

	// > onMetaData()
	if err = self.writeDataMsg(5, self.avmsgsid, "onMetaData", metadata); err != nil {
		return
	}

	// > Videodata(decoder config)
	// > Audiodata(decoder config)
	for _, stream := range streams {
		var ok bool
		var tag flvio.Tag
		if tag, ok, err = flv.CodecDataToTag(stream); err != nil {
			return
		}
		if ok {
			if err = self.writeAVTag(tag, 0); err != nil {
				return
			}
		}
	}

	self.streams = streams
	self.stage++
	return
}

func (self *Conn) tmpwbuf(n int) []byte {
	if len(self.writebuf) < n {
		self.writebuf = make([]byte, n)
	}
	return self.writebuf
}

func (self *Conn) writeSetChunkSize(size int) (err error) {
	self.writeMaxChunkSize = size
	b := self.tmpwbuf(chunkHeaderLength + 4)
	n := self.fillChunkHeader(b, 2, 0, msgtypeidSetChunkSize, 0, 4)
	pio.PutU32BE(b[n:], uint32(size))
	n += 4
	_, err = self.bufw.Write(b[:n])
	return
}

func (self *Conn) writeAck(seqnum uint32) (err error) {
	b := self.tmpwbuf(chunkHeaderLength + 4)
	n := self.fillChunkHeader(b, 2, 0, msgtypeidAck, 0, 4)
	pio.PutU32BE(b[n:], seqnum)
	n += 4
	_, err = self.bufw.Write(b[:n])
	return
}

func (self *Conn) writeWindowAckSize(size uint32) (err error) {
	b := self.tmpwbuf(chunkHeaderLength + 4)
	n := self.fillChunkHeader(b, 2, 0, msgtypeidWindowAckSize, 0, 4)
	pio.PutU32BE(b[n:], size)
	n += 4
	_, err = self.bufw.Write(b[:n])
	return
}

func (self *Conn) writeSetPeerBandwidth(acksize uint32, limittype uint8) (err error) {
	b := self.tmpwbuf(chunkHeaderLength + 5)
	n := self.fillChunkHeader(b, 2, 0, msgtypeidSetPeerBandwidth, 0, 5)
	pio.PutU32BE(b[n:], acksize)
	n += 4
	b[n] = limittype
	n++
	_, err = self.bufw.Write(b[:n])
	return
}

func (self *Conn) writeCommandMsg(csid, msgsid uint32, args ...interface{}) (err error) {
	return self.writeAMF0Msg(msgtypeidCommandMsgAMF0, csid, msgsid, args...)
}

func (self *Conn) writeDataMsg(csid, msgsid uint32, args ...interface{}) (err error) {
	return self.writeAMF0Msg(msgtypeidDataMsgAMF0, csid, msgsid, args...)
}

func (self *Conn) writeAMF0Msg(msgtypeid uint8, csid, msgsid uint32, args ...interface{}) (err error) {
	size := 0
	for _, arg := range args {
		size += flvio.LenAMF0Val(arg)
	}

	b := self.tmpwbuf(chunkHeaderLength + size)
	n := self.fillChunkHeader(b, csid, 0, msgtypeid, msgsid, size)
	for _, arg := range args {
		n += flvio.FillAMF0Val(b[n:], arg)
	}

	_, err = self.bufw.Write(b[:n])
	return
}

func (self *Conn) writeAVTag(tag flvio.Tag, ts int32) (err error) {
	var msgtypeid uint8
	var csid uint32
	var data []byte

	switch tag.Type {
	case flvio.TAG_AUDIO:
		msgtypeid = msgtypeidAudioMsg
		csid = 6
		data = tag.Data

	case flvio.TAG_VIDEO:
		msgtypeid = msgtypeidVideoMsg
		csid = 7
		data = tag.Data
	}

	actualChunkHeaderLength := chunkHeaderLength
	if uint32(ts) > FlvTimestampMax {
		actualChunkHeaderLength += 4
	}

	b := self.tmpwbuf(actualChunkHeaderLength + flvio.MaxTagSubHeaderLength)
	hdrlen := tag.FillHeader(b[actualChunkHeaderLength:])
	self.fillChunkHeader(b, csid, ts, msgtypeid, self.avmsgsid, hdrlen+len(data))
	n := hdrlen + actualChunkHeaderLength

	if n+len(data) > self.writeMaxChunkSize {
		if err = self.writeSetChunkSize(n + len(data)); err != nil {
			return
		}
	}

	if _, err = self.bufw.Write(b[:n]); err != nil {
		return
	}
	_, err = self.bufw.Write(data)
	return
}

func (self *Conn) writeStreamBegin(msgsid uint32) (err error) {
	b := self.tmpwbuf(chunkHeaderLength + 6)
	n := self.fillChunkHeader(b, 2, 0, msgtypeidUserControl, 0, 6)
	pio.PutU16BE(b[n:], eventtypeStreamBegin)
	n += 2
	pio.PutU32BE(b[n:], msgsid)
	n += 4
	_, err = self.bufw.Write(b[:n])
	return
}

func (self *Conn) writeSetBufferLength(msgsid uint32, timestamp uint32) (err error) {
	b := self.tmpwbuf(chunkHeaderLength + 10)
	n := self.fillChunkHeader(b, 2, 0, msgtypeidUserControl, 0, 10)
	pio.PutU16BE(b[n:], eventtypeSetBufferLength)
	n += 2
	pio.PutU32BE(b[n:], msgsid)
	n += 4
	pio.PutU32BE(b[n:], timestamp)
	n += 4
	_, err = self.bufw.Write(b[:n])
	return
}

const chunkHeaderLength = 12
const FlvTimestampMax = 0xFFFFFF

func (self *Conn) fillChunkHeader(b []byte, csid uint32, timestamp int32, msgtypeid uint8, msgsid uint32, msgdatalen int) (n int) {
	//  0                   1                   2                   3
	//  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	// |                   timestamp                   |message length |
	// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	// |     message length (cont)     |message type id| msg stream id |
	// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	// |           message stream id (cont)            |
	// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	//
	//       Figure 9 Chunk Message Header – Type 0

	b[n] = byte(csid) & 0x3f
	n++
	if uint32(timestamp) <= FlvTimestampMax {
		pio.PutU24BE(b[n:], uint32(timestamp))
	} else {
		pio.PutU24BE(b[n:], FlvTimestampMax)
	}
	n += 3
	pio.PutU24BE(b[n:], uint32(msgdatalen))
	n += 3
	b[n] = msgtypeid
	n++
	pio.PutU32LE(b[n:], msgsid)
	n += 4
	if uint32(timestamp) > FlvTimestampMax {
		pio.PutU32BE(b[n:], uint32(timestamp))
		n += 4
	}

	if Debug {
		fmt.Printf("rtmp: write chunk msgdatalen=%d msgsid=%d\n", msgdatalen, msgsid)
	}

	return
}

func (self *Conn) flushWrite() (err error) {
	if err = self.bufw.Flush(); err != nil {
		return
	}
	return
}

func (self *Conn) readChunk() (err error) {
	b := self.readbuf
	n := 0
	if _, err = io.ReadFull(self.bufr, b[:1]); err != nil {
		return
	}
	header := b[0]
	n += 1

	var msghdrtype uint8
	var csid uint32

	msghdrtype = header >> 6

	csid = uint32(header) & 0x3f
	switch csid {
	default: // Chunk basic header 1
	case 0: // Chunk basic header 2
		if _, err = io.ReadFull(self.bufr, b[:1]); err != nil {
			return
		}
		n += 1
		csid = uint32(b[0]) + 64
	case 1: // Chunk basic header 3
		if _, err = io.ReadFull(self.bufr, b[:2]); err != nil {
			return
		}
		n += 2
		csid = uint32(pio.U16BE(b)) + 64
	}

	cs := self.readcsmap[csid]
	if cs == nil {
		cs = &chunkStream{}
		self.readcsmap[csid] = cs
	}

	var timestamp uint32

	switch msghdrtype {
	case 0:
		//  0                   1                   2                   3
		//  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
		// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
		// |                   timestamp                   |message length |
		// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
		// |     message length (cont)     |message type id| msg stream id |
		// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
		// |           message stream id (cont)            |
		// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
		//
		//       Figure 9 Chunk Message Header – Type 0
		if cs.msgdataleft != 0 {
			err = fmt.Errorf("rtmp: chunk msgdataleft=%d invalid", cs.msgdataleft)
			return
		}
		h := b[:11]
		if _, err = io.ReadFull(self.bufr, h); err != nil {
			return
		}
		n += len(h)
		timestamp = pio.U24BE(h[0:3])
		cs.msghdrtype = msghdrtype
		cs.msgdatalen = pio.U24BE(h[3:6])
		cs.msgtypeid = h[6]
		cs.msgsid = pio.U32LE(h[7:11])
		if timestamp == 0xffffff {
			if _, err = io.ReadFull(self.bufr, b[:4]); err != nil {
				return
			}
			n += 4
			timestamp = pio.U32BE(b)
			cs.hastimeext = true
		} else {
			cs.hastimeext = false
		}
		cs.timenow = timestamp
		cs.Start()

	case 1:
		//  0                   1                   2                   3
		//  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
		// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
		// |                timestamp delta                |message length |
		// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
		// |     message length (cont)     |message type id|
		// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
		//
		//       Figure 10 Chunk Message Header – Type 1
		if cs.msgdataleft != 0 {
			err = fmt.Errorf("rtmp: chunk msgdataleft=%d invalid", cs.msgdataleft)
			return
		}
		h := b[:7]
		if _, err = io.ReadFull(self.bufr, h); err != nil {
			return
		}
		n += len(h)
		timestamp = pio.U24BE(h[0:3])
		cs.msghdrtype = msghdrtype
		cs.msgdatalen = pio.U24BE(h[3:6])
		cs.msgtypeid = h[6]
		if timestamp == 0xffffff {
			if _, err = io.ReadFull(self.bufr, b[:4]); err != nil {
				return
			}
			n += 4
			timestamp = pio.U32BE(b)
			cs.hastimeext = true
		} else {
			cs.hastimeext = false
		}
		cs.timedelta = timestamp
		cs.timenow += timestamp
		cs.Start()

	case 2:
		//  0                   1                   2
		//  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
		// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
		// |                timestamp delta                |
		// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
		//
		//       Figure 11 Chunk Message Header – Type 2
		if cs.msgdataleft != 0 {
			err = fmt.Errorf("rtmp: chunk msgdataleft=%d invalid", cs.msgdataleft)
			return
		}
		h := b[:3]
		if _, err = io.ReadFull(self.bufr, h); err != nil {
			return
		}
		n += len(h)
		cs.msghdrtype = msghdrtype
		timestamp = pio.U24BE(h[0:3])
		if timestamp == 0xffffff {
			if _, err = io.ReadFull(self.bufr, b[:4]); err != nil {
				return
			}
			n += 4
			timestamp = pio.U32BE(b)
			cs.hastimeext = true
		} else {
			cs.hastimeext = false
		}
		cs.timedelta = timestamp
		cs.timenow += timestamp
		cs.Start()

	case 3:
		if cs.msgdataleft == 0 {
			switch cs.msghdrtype {
			case 0:
				if cs.hastimeext {
					if _, err = io.ReadFull(self.bufr, b[:4]); err != nil {
						return
					}
					n += 4
					timestamp = pio.U32BE(b)
					cs.timenow = timestamp
				}
			case 1, 2:
				if cs.hastimeext {
					if _, err = io.ReadFull(self.bufr, b[:4]); err != nil {
						return
					}
					n += 4
					timestamp = pio.U32BE(b)
				} else {
					timestamp = cs.timedelta
				}
				cs.timenow += timestamp
			}
			cs.Start()
		}

	default:
		err = fmt.Errorf("rtmp: invalid chunk msg header type=%d", msghdrtype)
		return
	}

	size := int(cs.msgdataleft)
	if size > self.readMaxChunkSize {
		size = self.readMaxChunkSize
	}
	off := cs.msgdatalen - cs.msgdataleft
	buf := cs.msgdata[off : int(off)+size]
	if _, err = io.ReadFull(self.bufr, buf); err != nil {
		return
	}
	n += len(buf)
	cs.msgdataleft -= uint32(size)

	if Debug {
		fmt.Printf("rtmp: chunk msgsid=%d msgtypeid=%d msghdrtype=%d len=%d left=%d\n",
			cs.msgsid, cs.msgtypeid, cs.msghdrtype, cs.msgdatalen, cs.msgdataleft)
	}

	if cs.msgdataleft == 0 {
		if Debug {
			fmt.Println("rtmp: chunk data")
			fmt.Print(hex.Dump(cs.msgdata))
		}

		if err = self.handleMsg(cs.timenow, cs.msgsid, cs.msgtypeid, cs.msgdata); err != nil {
			return
		}
	}

	self.ackn += uint32(n)
	if self.readAckSize != 0 && self.ackn > self.readAckSize {
		if err = self.writeAck(self.ackn); err != nil {
			return
		}
		self.ackn = 0
	}

	return
}

func (self *Conn) handleCommandMsgAMF0(b []byte) (n int, err error) {
	var name, transid, obj interface{}
	var size int

	if name, size, err = flvio.ParseAMF0Val(b[n:]); err != nil {
		return
	}
	n += size
	if transid, size, err = flvio.ParseAMF0Val(b[n:]); err != nil {
		return
	}
	n += size
	if obj, size, err = flvio.ParseAMF0Val(b[n:]); err != nil {
		return
	}
	n += size

	var ok bool
	if self.commandname, ok = name.(string); !ok {
		err = fmt.Errorf("rtmp: CommandMsgAMF0 command is not string")
		return
	}
	self.commandtransid, _ = transid.(float64)
	self.commandobj, _ = obj.(flvio.AMFMap)
	self.commandparams = []interface{}{}

	for n < len(b) {
		if obj, size, err = flvio.ParseAMF0Val(b[n:]); err != nil {
			return
		}
		n += size
		self.commandparams = append(self.commandparams, obj)
	}
	if n < len(b) {
		err = fmt.Errorf("rtmp: CommandMsgAMF0 left bytes=%d", len(b)-n)
		return
	}

	self.gotcommand = true
	return
}

func (self *Conn) handleMsg(timestamp uint32, msgsid uint32, msgtypeid uint8, msgdata []byte) (err error) {
	self.msgdata = msgdata
	self.msgtypeid = msgtypeid
	self.timestamp = timestamp

	switch msgtypeid {
	case msgtypeidCommandMsgAMF0:
		if _, err = self.handleCommandMsgAMF0(msgdata); err != nil {
			return
		}

	case msgtypeidCommandMsgAMF3:
		if len(msgdata) < 1 {
			err = fmt.Errorf("rtmp: short packet of CommandMsgAMF3")
			return
		}
		// skip first byte
		if _, err = self.handleCommandMsgAMF0(msgdata[1:]); err != nil {
			return
		}

	case msgtypeidUserControl:
		if len(msgdata) < 2 {
			err = fmt.Errorf("rtmp: short packet of UserControl")
			return
		}
		self.eventtype = pio.U16BE(msgdata)

	case msgtypeidDataMsgAMF0:
		b := msgdata
		n := 0
		for n < len(b) {
			var obj interface{}
			var size int
			if obj, size, err = flvio.ParseAMF0Val(b[n:]); err != nil {
				return
			}
			n += size
			self.datamsgvals = append(self.datamsgvals, obj)
		}
		if n < len(b) {
			err = fmt.Errorf("rtmp: DataMsgAMF0 left bytes=%d", len(b)-n)
			return
		}

	case msgtypeidVideoMsg:
		if len(msgdata) == 0 {
			return
		}
		tag := flvio.Tag{Type: flvio.TAG_VIDEO}
		var n int
		if n, err = (&tag).ParseHeader(msgdata); err != nil {
			return
		}
		if !(tag.FrameType == flvio.FRAME_INTER || tag.FrameType == flvio.FRAME_KEY) {
			return
		}
		tag.Data = msgdata[n:]
		self.avtag = tag

	case msgtypeidAudioMsg:
		if len(msgdata) == 0 {
			return
		}
		tag := flvio.Tag{Type: flvio.TAG_AUDIO}
		var n int
		if n, err = (&tag).ParseHeader(msgdata); err != nil {
			return
		}
		tag.Data = msgdata[n:]
		self.avtag = tag

	case msgtypeidSetChunkSize:
		if len(msgdata) < 4 {
			err = fmt.Errorf("rtmp: short packet of SetChunkSize")
			return
		}
		self.readMaxChunkSize = int(pio.U32BE(msgdata))
		return
	}

	self.gotmsg = true
	return
}

var (
	hsClientFullKey = []byte{
		'G', 'e', 'n', 'u', 'i', 'n', 'e', ' ', 'A', 'd', 'o', 'b', 'e', ' ',
		'F', 'l', 'a', 's', 'h', ' ', 'P', 'l', 'a', 'y', 'e', 'r', ' ',
		'0', '0', '1',
		0xF0, 0xEE, 0xC2, 0x4A, 0x80, 0x68, 0xBE, 0xE8, 0x2E, 0x00, 0xD0, 0xD1,
		0x02, 0x9E, 0x7E, 0x57, 0x6E, 0xEC, 0x5D, 0x2D, 0x29, 0x80, 0x6F, 0xAB,
		0x93, 0xB8, 0xE6, 0x36, 0xCF, 0xEB, 0x31, 0xAE,
	}
	hsServerFullKey = []byte{
		'G', 'e', 'n', 'u', 'i', 'n', 'e', ' ', 'A', 'd', 'o', 'b', 'e', ' ',
		'F', 'l', 'a', 's', 'h', ' ', 'M', 'e', 'd', 'i', 'a', ' ',
		'S', 'e', 'r', 'v', 'e', 'r', ' ',
		'0', '0', '1',
		0xF0, 0xEE, 0xC2, 0x4A, 0x80, 0x68, 0xBE, 0xE8, 0x2E, 0x00, 0xD0, 0xD1,
		0x02, 0x9E, 0x7E, 0x57, 0x6E, 0xEC, 0x5D, 0x2D, 0x29, 0x80, 0x6F, 0xAB,
		0x93, 0xB8, 0xE6, 0x36, 0xCF, 0xEB, 0x31, 0xAE,
	}
	hsClientPartialKey = hsClientFullKey[:30]
	hsServerPartialKey = hsServerFullKey[:36]
)

func hsMakeDigest(key []byte, src []byte, gap int) (dst []byte) {
	h := hmac.New(sha256.New, key)
	if gap <= 0 {
		h.Write(src)
	} else {
		h.Write(src[:gap])
		h.Write(src[gap+32:])
	}
	return h.Sum(nil)
}

func hsCalcDigestPos(p []byte, base int) (pos int) {
	for i := 0; i < 4; i++ {
		pos += int(p[base+i])
	}
	pos = (pos % 728) + base + 4
	return
}

func hsFindDigest(p []byte, key []byte, base int) int {
	gap := hsCalcDigestPos(p, base)
	digest := hsMakeDigest(key, p, gap)
	if bytes.Compare(p[gap:gap+32], digest) != 0 {
		return -1
	}
	return gap
}

func hsParse1(p []byte, peerkey []byte, key []byte) (ok bool, digest []byte) {
	var pos int
	if pos = hsFindDigest(p, peerkey, 772); pos == -1 {
		if pos = hsFindDigest(p, peerkey, 8); pos == -1 {
			return
		}
	}
	ok = true
	digest = hsMakeDigest(key, p[pos:pos+32], -1)
	return
}

func hsCreate01(p []byte, time uint32, ver uint32, key []byte) {
	p[0] = 3
	p1 := p[1:]
	rand.Read(p1[8:])
	pio.PutU32BE(p1[0:4], time)
	pio.PutU32BE(p1[4:8], ver)
	gap := hsCalcDigestPos(p1, 8)
	digest := hsMakeDigest(key, p1, gap)
	copy(p1[gap:], digest)
}

func hsCreate2(p []byte, key []byte) {
	rand.Read(p)
	gap := len(p) - 32
	digest := hsMakeDigest(key, p, gap)
	copy(p[gap:], digest)
}

func (self *Conn) handshakeClient() (err error) {
	var random [(1 + 1536*2) * 2]byte

	C0C1C2 := random[:1536*2+1]
	C0 := C0C1C2[:1]
	//C1 := C0C1C2[1:1536+1]
	C0C1 := C0C1C2[:1536+1]
	C2 := C0C1C2[1536+1:]

	S0S1S2 := random[1536*2+1:]
	//S0 := S0S1S2[:1]
	S1 := S0S1S2[1 : 1536+1]
	//S0S1 := S0S1S2[:1536+1]
	//S2 := S0S1S2[1536+1:]

	C0[0] = 3
	//hsCreate01(C0C1, hsClientFullKey)

	// > C0C1
	if _, err = self.bufw.Write(C0C1); err != nil {
		return
	}
	if err = self.bufw.Flush(); err != nil {
		return
	}

	// < S0S1S2
	if _, err = io.ReadFull(self.bufr, S0S1S2); err != nil {
		return
	}

	if Debug {
		fmt.Println("rtmp: handshakeClient: server version", S1[4], S1[5], S1[6], S1[7])
	}

	if ver := pio.U32BE(S1[4:8]); ver != 0 {
		C2 = S1
	} else {
		C2 = S1
	}

	// > C2
	if _, err = self.bufw.Write(C2); err != nil {
		return
	}

	self.stage++
	return
}

func (self *Conn) handshakeServer() (err error) {
	var random [(1 + 1536*2) * 2]byte

	C0C1C2 := random[:1536*2+1]
	C0 := C0C1C2[:1]
	C1 := C0C1C2[1 : 1536+1]
	C0C1 := C0C1C2[:1536+1]
	C2 := C0C1C2[1536+1:]

	S0S1S2 := random[1536*2+1:]
	S0 := S0S1S2[:1]
	S1 := S0S1S2[1 : 1536+1]
	S0S1 := S0S1S2[:1536+1]
	S2 := S0S1S2[1536+1:]

	// < C0C1
	if _, err = io.ReadFull(self.bufr, C0C1); err != nil {
		return
	}
	if C0[0] != 3 {
		err = fmt.Errorf("rtmp: handshake version=%d invalid", C0[0])
		return
	}

	S0[0] = 3

	clitime := pio.U32BE(C1[0:4])
	srvtime := clitime
	srvver := uint32(0x0d0e0a0d)
	cliver := pio.U32BE(C1[4:8])

	if cliver != 0 {
		var ok bool
		var digest []byte
		if ok, digest = hsParse1(C1, hsClientPartialKey, hsServerFullKey); !ok {
			err = fmt.Errorf("rtmp: handshake server: C1 invalid")
			return
		}
		hsCreate01(S0S1, srvtime, srvver, hsServerPartialKey)
		hsCreate2(S2, digest)
	} else {
		copy(S1, C1)
		copy(S2, C2)
	}

	// > S0S1S2
	if _, err = self.bufw.Write(S0S1S2); err != nil {
		return
	}
	if err = self.bufw.Flush(); err != nil {
		return
	}

	// < C2
	if _, err = io.ReadFull(self.bufr, C2); err != nil {
		return
	}

	self.stage++
	return
}

type closeConn struct {
	*Conn
	waitclose chan bool
}

func (self closeConn) Close() error {
	self.waitclose <- true
	return nil
}

func Handler(h *avutil.RegisterHandler) {
	h.UrlDemuxer = func(uri string) (ok bool, demuxer av.DemuxCloser, err error) {
		if !strings.HasPrefix(uri, "rtmp://") {
			return
		}
		ok = true
		demuxer, err = Dial(uri)
		return
	}

	h.UrlMuxer = func(uri string) (ok bool, muxer av.MuxCloser, err error) {
		if !strings.HasPrefix(uri, "rtmp://") {
			return
		}
		ok = true
		muxer, err = Dial(uri)
		return
	}

	h.ServerMuxer = func(uri string) (ok bool, muxer av.MuxCloser, err error) {
		if !strings.HasPrefix(uri, "rtmp://") {
			return
		}
		ok = true

		var u *url.URL
		if u, err = ParseURL(uri); err != nil {
			return
		}
		server := &Server{
			Addr: u.Host,
		}

		waitstart := make(chan error)
		waitconn := make(chan *Conn)
		waitclose := make(chan bool)

		server.HandlePlay = func(conn *Conn) {
			waitconn <- conn
			<-waitclose
		}

		go func() {
			waitstart <- server.ListenAndServe()
		}()

		select {
		case err = <-waitstart:
			if err != nil {
				return
			}

		case conn := <-waitconn:
			muxer = closeConn{Conn: conn, waitclose: waitclose}
			return
		}

		return
	}

	h.ServerDemuxer = func(uri string) (ok bool, demuxer av.DemuxCloser, err error) {
		if !strings.HasPrefix(uri, "rtmp://") {
			return
		}
		ok = true

		var u *url.URL
		if u, err = ParseURL(uri); err != nil {
			return
		}
		server := &Server{
			Addr: u.Host,
		}

		waitstart := make(chan error)
		waitconn := make(chan *Conn)
		waitclose := make(chan bool)

		server.HandlePublish = func(conn *Conn) {
			waitconn <- conn
			<-waitclose
		}

		go func() {
			waitstart <- server.ListenAndServe()
		}()

		select {
		case err = <-waitstart:
			if err != nil {
				return
			}

		case conn := <-waitconn:
			demuxer = closeConn{Conn: conn, waitclose: waitclose}
			return
		}

		return
	}

	h.CodecTypes = CodecTypes
}


================================================
FILE: format/rtsp/client.go
================================================
package rtsp

import (
	"bufio"
	"bytes"
	"crypto/md5"
	"encoding/base64"
	"encoding/binary"
	"encoding/hex"
	"fmt"
	"github.com/nareix/joy4/utils/bits/pio"
	"github.com/nareix/joy4/av"
	"github.com/nareix/joy4/av/avutil"
	"github.com/nareix/joy4/codec"
	"github.com/nareix/joy4/codec/aacparser"
	"github.com/nareix/joy4/codec/h264parser"
	"github.com/nareix/joy4/format/rtsp/sdp"
	"io"
	"net"
	"net/textproto"
	"net/url"
	"strconv"
	"strings"
	"time"
)

var ErrCodecDataChange = fmt.Errorf("rtsp: codec data change, please call HandleCodecDataChange()")

var DebugRtp = false
var DebugRtsp = false
var SkipErrRtpBlock = false

const (
	stageDescribeDone = iota+1
	stageSetupDone
	stageWaitCodecData
	stageCodecDataDone
)

type Client struct {
	DebugRtsp bool
	DebugRtp bool
	Headers   []string

	SkipErrRtpBlock bool

	RtspTimeout          time.Duration
	RtpTimeout           time.Duration
	RtpKeepAliveTimeout  time.Duration
	rtpKeepaliveTimer    time.Time
	rtpKeepaliveEnterCnt int

	stage int

	setupIdx    []int
	setupMap    []int

	authHeaders func(method string) []string

	url        *url.URL
	conn       *connWithTimeout
	brconn      *bufio.Reader
	requestUri string
	cseq       uint
	streams    []*Stream
	streamsintf []av.CodecData
	session    string
	body       io.Reader
}

type Request struct {
	Header []string
	Uri    string
	Method string
}

type Response struct {
	StatusCode    int
	Headers        textproto.MIMEHeader
	ContentLength int
	Body          []byte

	Block []byte
}

func DialTimeout(uri string, timeout time.Duration) (self *Client, err error) {
	var URL *url.URL
	if URL, err = url.Parse(uri); err != nil {
		return
	}

	if _, _, err := net.SplitHostPort(URL.Host); err != nil {
		URL.Host = URL.Host + ":554"
	}

	dailer := net.Dialer{Timeout: timeout}
	var conn net.Conn
	if conn, err = dailer.Dial("tcp", URL.Host); err != nil {
		return
	}

	u2 := *URL
	u2.User = nil

	connt := &connWithTimeout{Conn: conn}

	self = &Client{
		conn:       connt,
		brconn:     bufio.NewReaderSize(connt, 256),
		url:        URL,
		requestUri: u2.String(),
		DebugRtp:   DebugRtp,
		DebugRtsp:  DebugRtsp,
		SkipErrRtpBlock: SkipErrRtpBlock,
	}
	return
}

func Dial(uri string) (self *Client, err error) {
	return DialTimeout(uri, 0)
}

func (self *Client) allCodecDataReady() bool {
	for _, si:= range self.setupIdx {
		stream := self.streams[si]
		if stream.CodecData == nil {
			return false
		}
	}
	return true
}

func (self *Client) probe() (err error) {
	for {
		if self.allCodecDataReady() {
			break
		}
		if _, err = self.readPacket(); err != nil {
			return
		}
	}
	self.stage = stageCodecDataDone
	return
}

func (self *Client) prepare(stage int) (err error) {
	for self.stage < stage {
		switch self.stage {
		case 0:
			if _, err = self.Describe(); err != nil {
				return
			}

		case stageDescribeDone:
			if err = self.SetupAll(); err != nil {
				return
			}

		case stageSetupDone:
			if err = self.Play(); err != nil {
				return
			}

		case stageWaitCodecData:
			if err = self.probe(); err != nil {
				return
			}
		}
	}
	return
}

func (self *Client) Streams() (streams []av.CodecData, err error) {
	if err = self.prepare(stageCodecDataDone); err != nil {
		return
	}
	for _, si := range self.setupIdx {
		stream := self.streams[si]
		streams = append(streams, stream.CodecData)
	}
	return
}

func (self *Client) SendRtpKeepalive() (err error) {
	if self.RtpKeepAliveTimeout > 0 {
		if self.rtpKeepaliveTimer.IsZero() {
			self.rtpKeepaliveTimer = time.Now()
		} else if time.Now().Sub(self.rtpKeepaliveTimer) > self.RtpKeepAliveTimeout {
			self.rtpKeepaliveTimer = time.Now()
			if self.DebugRtsp {
				fmt.Println("rtp: keep alive")
			}
			req := Request{
				Method: "OPTIONS",
				Uri:    self.requestUri,
			}
			if err = self.WriteRequest(req); err != nil {
				return
			}
		}
	}
	return
}

func (self *Client) WriteRequest(req Request) (err error) {
	self.conn.Timeout = self.RtspTimeout
	self.cseq++

	buf := &bytes.Buffer{}

	fmt.Fprintf(buf, "%s %s RTSP/1.0\r\n", req.Method, req.Uri)
	fmt.Fprintf(buf, "CSeq: %d\r\n", self.cseq)

	if self.authHeaders != nil {
		headers := self.authHeaders(req.Method)
		for _, s := range headers {
			io.WriteString(buf, s)
			io.WriteString(buf, "\r\n")
		}
	}
	for _, s := range req.Header {
		io.WriteString(buf, s)
		io.WriteString(buf, "\r\n")
	}
	for _, s := range self.Headers {
		io.WriteString(buf, s)
		io.WriteString(buf, "\r\n")
	}
	io.WriteString(buf, "\r\n")

	bufout := buf.Bytes()

	if self.DebugRtsp {
		fmt.Print("> ", string(bufout))
	}

	if _, err = self.conn.Write(bufout); err != nil {
		return
	}

	return
}

func (self *Client) parseBlockHeader(h []byte) (length int, no int, valid bool) {
	length = int(h[2])<<8 + int(h[3])
	no = int(h[1])
	if no/2 >= len(self.streams) {
		return
	}

	if no%2 == 0 { // rtp
		if length < 8 {
			return
		}

		// V=2
		if h[4]&0xc0 != 0x80 {
			return
		}

		stream := self.streams[no/2]
		if int(h[5]&0x7f) != stream.Sdp.PayloadType {
			return
		}

		timestamp := binary.BigEndian.Uint32(h[8:12])
		if stream.firsttimestamp != 0 {
			timestamp -= stream.firsttimestamp
			if timestamp < stream.timestamp {
				return
			} else if timestamp - stream.timestamp > uint32(stream.timeScale()*60*60) {
				return
			}
		}
	} else { // rtcp
	}

	valid = true
	return
}

func (self *Client) parseHeaders(b []byte) (statusCode int, headers textproto.MIMEHeader, err error) {
	var line string
	r := textproto.NewReader(bufio.NewReader(bytes.NewReader(b)))
	if line, err = r.ReadLine(); err != nil {
		err = fmt.Errorf("rtsp: header invalid")
		return
	}

	if codes := strings.Split(line, " "); len(codes) >= 2 {
		if statusCode, err = strconv.Atoi(codes[1]); err != nil {
			err = fmt.Errorf("rtsp: header invalid: %s", err)
			return
		}
	}

	headers, _ = r.ReadMIMEHeader()
	return
}

func (self *Client) handleResp(res *Response) (err error) {
	if sess := res.Headers.Get("Session"); sess != "" && self.session == "" {
		if fields := strings.Split(sess, ";"); len(fields) > 0 {
			self.session = fields[0]
		}
	}
	if res.StatusCode == 401 {
		if err = self.handle401(res); err != nil {
			return
		}
	}
	return
}

func (self *Client) handle401(res *Response) (err error) {
	/*
		RTSP/1.0 401 Unauthorized
		CSeq: 2
		Date: Wed, May 04 2016 10:10:51 GMT
		WWW-Authenticate: Digest realm="LIVE555 Streaming Media", nonce="c633aaf8b83127633cbe98fac1d20d87"
	*/
	authval := res.Headers.Get("WWW-Authenticate")
	hdrval := strings.SplitN(authval, " ", 2)
	var realm, nonce string

	if len(hdrval) == 2 {
		for _, field := range strings.Split(hdrval[1], ",") {
			field = strings.Trim(field, ", ")
			if keyval := strings.Split(field, "="); len(keyval) == 2 {
				key := keyval[0]
				val := strings.Trim(keyval[1], `"`)
				switch key {
				case "realm":
					realm = val
				case "nonce":
					nonce = val
				}
			}
		}

		if realm != "" {
			var username string
			var password string

			if self.url.User == nil {
				err = fmt.Errorf("rtsp: no username")
				return
			}
			username = self.url.User.Username()
			password, _ = self.url.User.Password()

			self.authHeaders = func(method string) []string {
				var headers []string
				if nonce == "" {
					headers = []string{
						fmt.Sprintf(`Authorization: Basic %s`, base64.StdEncoding.EncodeToString([]byte(username+":"+password))),
					}
				} else {
					hs1 := md5hash(username + ":" + realm + ":" + password)
					hs2 := md5hash(method + ":" + self.requestUri)
					response := md5hash(hs1 + ":" + nonce + ":" + hs2)
					headers = []string{fmt.Sprintf(
						`Authorization: Digest username="%s", realm="%s", nonce="%s", uri="%s", response="%s"`,
						username, realm, nonce, self.requestUri, response)}
				}
				return headers
			}
		}
	}

	return
}

func (self *Client) findRTSP() (block []byte, data []byte, err error) {
	const (
		R = iota+1
		T
		S
		Header
		Dollar
	)
	var _peek [8]byte
	peek := _peek[0:0]
	stat := 0

	for i := 0;; i++ {
		var b byte
		if b, err = self.brconn.ReadByte(); err != nil {
			return
		}
		switch b {
		case 'R':
			if stat == 0 {
				stat = R
			}
		case 'T':
			if stat == R {
				stat = T
			}
		case 'S':
			if stat == T {
				stat = S
			}
		case 'P':
			if stat == S {
				stat = Header
			}
		case '$':
			if stat != Dollar {
				stat = Dollar
				peek = _peek[0:0]
			}
		default:
			if stat != Dollar {
				stat = 0
				peek = _peek[0:0]
			}
		}

		if false && self.DebugRtp {
			fmt.Println("rtsp: findRTSP", i, b)
		}

		if stat != 0 {
			peek = append(peek, b)
		}
		if stat == Header {
			data = peek
			return
		}

		if stat == Dollar && len(peek) >= 12 {
			if self.DebugRtp {
				fmt.Println("rtsp: dollar at", i, len(peek))
			}
			if blocklen, _, ok := self.parseBlockHeader(peek); ok {
				left := blocklen+4-len(peek)
				block = append(peek, make([]byte, left)...)
				if _, err = io.ReadFull(self.brconn, block[len(peek):]); err != nil {
					return
				}
				return
			}
			stat = 0
			peek = _peek[0:0]
		}
	}

	return
}

func (self *Client) readLFLF() (block []byte, data []byte, err error) {
	const (
		LF = iota+1
		LFLF
	)
	peek := []byte{}
	stat := 0
	dollarpos := -1
	lpos := 0
	pos := 0

	for {
		var b byte
		if b, err = self.brconn.ReadByte(); err != nil {
			return
		}
		switch b {
		case '\n':
			if stat == 0 {
				stat = LF
				lpos = pos
			} else if stat == LF {
				if pos - lpos <= 2 {
					stat = LFLF
				} else {
					lpos = pos
				}
			}
		case '$':
			dollarpos = pos
		}
		peek = append(peek, b)

		if stat == LFLF {
			data = peek
			return
		} else if dollarpos != -1 && dollarpos - pos >= 12 {
			hdrlen := dollarpos-pos
			start := len(peek)-hdrlen
			if blocklen, _, ok := self.parseBlockHeader(peek[start:]); ok {
				block = append(peek[start:], make([]byte, blocklen+4-hdrlen)...)
				if _, err = io.ReadFull(self.brconn, block[hdrlen:]); err != nil {
					return
				}
				return
			}
			dollarpos = -1
		}

		pos++
	}

	return
}

func (self *Client) readResp(b []byte) (res Response, err error) {
	if res.StatusCode, res.Headers, err = self.parseHeaders(b); err != nil {
		return
	}
	res.ContentLength, _ = strconv.Atoi(res.Headers.Get("Content-Length"))
	if res.ContentLength > 0 {
		res.Body = make([]byte, res.ContentLength)
		if _, err = io.ReadFull(self.brconn, res.Body); err != nil {
			return
		}
	}
	if err = self.handleResp(&res); err != nil {
		return
	}
	return
}

func (self *Client) poll() (res Response, err error) {
	var block []byte
	var rtsp []byte
	var headers []byte

	self.conn.Timeout = self.RtspTimeout
	for {
		if block, rtsp, err = self.findRTSP(); err != nil {
			return
		}
		if len(block) > 0 {
			res.Block = block
			return
		} else {
			if block, headers, err = self.readLFLF(); err != nil {
				return
			}
			if len(block) > 0 {
				res.Block = block
				return
			}
			if res, err = self.readResp(append(rtsp, headers...)); err != nil {
				return
			}
		}
		return
	}

	return
}

func (self *Client) ReadResponse() (res Response, err error) {
	for {
		if res, err = self.poll(); err != nil {
			return
		}
		if res.StatusCode > 0 {
			return
		}
	}
	return
}

func (self *Client) SetupAll() (err error) {
	idx := []int{}
	for i := range self.streams {
		idx = append(idx, i)
	}
	return self.Setup(idx)
}

func (self *Client) Setup(idx []int) (err error) {
	if err = self.prepare(stageDescribeDone); err != nil {
		return
	}

	self.setupMap = make([]int, len(self.streams))
	for i := range self.setupMap {
		self.setupMap[i] = -1
	}
	self.setupIdx = idx

	for i, si := range idx {
		self.setupMap[si] = i

		uri := ""
		control := self.streams[si].Sdp.Control
		if strings.HasPrefix(control, "rtsp://") {
			uri = control
		} else {
			uri = self.requestUri + "/" + control
		}
		req := Request{Method: "SETUP", Uri: uri}
		req.Header = append(req.Header, fmt.Sprintf("Transport: RTP/AVP/TCP;unicast;interleaved=%d-%d", si*2, si*2+1))
		if self.session != "" {
			req.Header = append(req.Header, "Session: "+self.session)
		}
		if err = self.WriteRequest(req); err != nil {
			return
		}
		if _, err = self.ReadResponse(); err != nil {
			return
		}
	}

	if self.stage == stageDescribeDone {
		self.stage = stageSetupDone
	}
	return
}

func md5hash(s string) string {
	h := md5.Sum([]byte(s))
	return hex.EncodeToString(h[:])
}

func (self *Client) Describe() (streams []sdp.Media, err error) {
	var res Response

	for i := 0; i < 2; i++ {
		req := Request{
			Method: "DESCRIBE",
			Uri:    self.requestUri,
			Header: []string{"Accept: application/sdp"},
		}
		if err = self.WriteRequest(req); err != nil {
			return
		}
		if res, err = self.ReadResponse(); err != nil {
			return
		}
		if res.StatusCode == 200 {
			break
		}
	}
	if res.ContentLength == 0 {
		err = fmt.Errorf("rtsp: Describe failed, StatusCode=%d", res.StatusCode)
		return
	}

	body := string(res.Body)

	if self.DebugRtsp {
		fmt.Println("<", body)
	}

	_, medias := sdp.Parse(body)

	self.streams = []*Stream{}
	for _, media := range medias {
		stream := &Stream{Sdp: media, client: self}
		stream.makeCodecData()
		self.streams = append(self.streams, stream)
		streams = append(streams, media)
	}

	if self.stage == 0 {
		self.stage = stageDescribeDone
	}
	return
}

func (self *Client) Options() (err error) {
	req := Request{
		Method: "OPTIONS",
		Uri:    self.requestUri,
	}
	if self.session != "" {
		req.Header = append(req.Header, "Session: "+self.session)
	}
	if err = self.WriteRequest(req); err != nil {
		return
	}
	if _, err = self.ReadResponse(); err != nil {
		return
	}
	return
}

func (self *Client) HandleCodecDataChange() (_newcli *Client, err error) {
	newcli := &Client{}
	*newcli = *self

	newcli.streams = []*Stream{}
	for _, stream := range self.streams {
		newstream := &Stream{}
		*newstream = *stream
		newstream.client = newcli

		if newstream.isCodecDataChange() {
			if err = newstream.makeCodecData(); err != nil {
				return
			}
			newstream.clearCodecDataChange()
		}
		newcli.streams = append(newcli.streams, newstream)
	}

	_newcli = newcli
	return
}

func (self *Stream) clearCodecDataChange() {
	self.spsChanged = false
	self.ppsChanged = false
}

func (self *Stream) isCodecDataChange() bool {
	if self.spsChanged && self.ppsChanged {
		return true
	}
	return false
}

func (self *Stream) timeScale() int {
	t := self.Sdp.TimeScale
	if t == 0 {
		// https://tools.ietf.org/html/rfc5391
		t = 8000
	}
	return t
}

func (self *Stream) makeCodecData() (err error) {
	media := self.Sdp

	if media.PayloadType >= 96 && media.PayloadType <= 127 {
		switch media.Type {
		case av.H264:
			for _, nalu := range media.SpropParameterSets {
				if len(nalu) > 0 {
					self.handleH264Payload(0, nalu)
				}
			}

			if len(self.sps) == 0 || len(self.pps) == 0 {
				if nalus, typ := h264parser.SplitNALUs(media.Config); typ != h264parser.NALU_RAW {
					for _, nalu := range nalus {
						if len(nalu) > 0 {
							self.handleH264Payload(0, nalu)
						}
					}
				}
			}

			if len(self.sps) > 0 && len(self.pps) > 0 {
				if self.CodecData, err = h264parser.NewCodecDataFromSPSAndPPS(self.sps, self.pps); err != nil {
					err = fmt.Errorf("rtsp: h264 sps/pps invalid: %s", err)
					return
				}
			} else {
				err = fmt.Errorf("rtsp: missing h264 sps or pps")
				return
			}

		case av.AAC:
			if len(media.Config) == 0 {
				err = fmt.Errorf("rtsp: aac sdp config missing")
				return
			}
			if self.CodecData, err = aacparser.NewCodecDataFromMPEG4AudioConfigBytes(media.Config); err != nil {
				err = fmt.Errorf("rtsp: aac sdp config invalid: %s", err)
				return
			}
		}
	} else {
		switch media.PayloadType {
		case 0:
			self.CodecData = codec.NewPCMMulawCodecData()

		case 8:
			self.CodecData = codec.NewPCMAlawCodecData()

		default:
			err = fmt.Errorf("rtsp: PayloadType=%d unsupported", media.PayloadType)
			return
		}
	}

	return
}

func (self *Stream) handleBuggyAnnexbH264Packet(timestamp uint32, packet []byte) (isBuggy bool, err error) {
	if len(packet) >= 4 && packet[0] == 0 && packet[1] == 0 && packet[2] == 0 && packet[3] == 1 {
		isBuggy = true
		if nalus, typ := h264parser.SplitNALUs(packet); typ != h264parser.NALU_RAW {
			for _, nalu := range nalus {
				if len(nalu) > 0 {
					if err = self.handleH264Payload(timestamp, nalu); err != nil {
						return
					}
				}
			}
		}
	}
	return
}

func (self *Stream) handleH264Payload(timestamp uint32, packet []byte) (err error) {
	if len(packet) < 2 {
		err = fmt.Errorf("rtp: h264 packet too short")
		return
	}

	var isBuggy bool
	if isBuggy, err = self.handleBuggyAnnexbH264Packet(timestamp, packet); isBuggy {
		return
	}

	naluType := packet[0]&0x1f

	/*
		Table 7-1 – NAL unit type codes
		1   Coded slice of a non-IDR picture
		5    Coded slice of an IDR picture
		6    Supplemental enhancement information (SEI)
		7    Sequence parameter set
		8    Picture parameter set
		1-23     NAL unit  Single NAL unit packet             5.6
		24       STAP-A    Single-time aggregation packet     5.7.1
		25       STAP-B    Single-time aggregation packet     5.7.1
		26       MTAP16    Multi-time aggregation packet      5.7.2
		27       MTAP24    Multi-time aggregation packet      5.7.2
		28       FU-A      Fragmentation unit                 5.8
		29       FU-B      Fragmentation unit                 5.8
		30-31    reserved                                     -
	*/
	switch {
	case naluType >= 1 && naluType <= 5:
			if naluType == 5 {
				self.pkt.IsKeyFrame = true
			}
			self.gotpkt = true
			// raw nalu to avcc
			b := make([]byte, 4+len(packet))
			pio.PutU32BE(b[0:4], uint32(len(packet)))
			copy(b[4:], packet)
			self.pkt.Data = b
			self.timestamp = timestamp

	case naluType == 7: // sps
		if self.client != nil && self.client.DebugRtp {
			fmt.Println("rtsp: got sps")
		}
		if len(self.sps) == 0 {
			self.sps = packet
			self.makeCodecData()
		} else if bytes.Compare(self.sps, packet) != 0 {
			self.spsChanged = true
			self.sps = packet
			if self.client != nil && self.client.DebugRtp {
				fmt.Println("rtsp: sps changed")
			}
		}

	case naluType == 8: // pps
		if self.client != nil && self.client.DebugRtp {
			fmt.Println("rtsp: got pps")
		}
		if len(self.pps) == 0 {
			self.pps = packet
			self.makeCodecData()
		} else if bytes.Compare(self.pps, packet) != 0 {
			self.ppsChanged = true
			self.pps = packet
			if self.client != nil && self.client.DebugRtp {
				fmt.Println("rtsp: pps changed")
			}
		}

	case naluType == 28: // FU-A
		/*
			0                   1                   2                   3
			0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
			+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
			| FU indicator  |   FU header   |                               |
			+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               |
			|                                                               |
			|                         FU payload                            |
			|                                                               |
			|                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
			|                               :...OPTIONAL RTP padding        |
			+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
			Figure 14.  RTP payload format for FU-A

			The FU indicator octet has the following format:
			+---------------+
			|0|1|2|3|4|5|6|7|
			+-+-+-+-+-+-+-+-+
			|F|NRI|  Type   |
			+---------------+


			The FU header has the following format:
			+---------------+
			|0|1|2|3|4|5|6|7|
			+-+-+-+-+-+-+-+-+
			|S|E|R|  Type   |
			+---------------+

			S: 1 bit
			When set to one, the Start bit indicates the start of a fragmented
			NAL unit.  When the following FU payload is not the start of a
			fragmented NAL unit payload, the Start bit is set to zero.

			E: 1 bit
			When set to one, the End bit indicates the end of a fragmented NAL
			unit, i.e., the last byte of the payload is also the last byte of
			the fragmented NAL unit.  When the following FU payload is not the
			last fragment of a fragmented NAL unit, the End bit is set to
			zero.

			R: 1 bit
			The Reserved bit MUST be equal to 0 and MUST be ignored by the
			receiver.

			Type: 5 bits
			The NAL unit payload type as defined in table 7-1 of [1].
		*/
		fuIndicator := packet[0]
		fuHeader := packet[1]
		isStart := fuHeader&0x80 != 0
		isEnd := fuHeader&0x40 != 0
		if isStart {
			self.fuStarted = true
			self.fuBuffer = []byte{fuIndicator&0xe0 | fuHeader&0x1f}
		}
		if self.fuStarted {
			self.fuBuffer = append(self.fuBuffer, packet[2:]...)
			if isEnd {
				self.fuStarted = false
				if err = self.handleH264Payload(timestamp, self.fuBuffer); err != nil {
					return
				}
			}
		}

	case naluType == 24: // STAP-A
		/*
		0                   1                   2                   3
		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
		|                          RTP Header                           |
		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
		|STAP-A NAL HDR |         NALU 1 Size           | NALU 1 HDR    |
		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
		|                         NALU 1 Data                           |
		:                                                               :
		+               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
		|               | NALU 2 Size                   | NALU 2 HDR    |
		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
		|                         NALU 2 Data                           |
		:                                                               :
		|                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
		|                               :...OPTIONAL RTP padding        |
		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

		Figure 7.  An example of an RTP packet including an STAP-A
		containing two single-time aggregation units
		*/
		packet = packet[1:]
		for len(packet) >= 2 {
			size := int(packet[0])<<8|int(packet[1])
			if size+2 > len(packet) {
				break
			}
			if err = self.handleH264Payload(timestamp, packet[2:size+2]); err != nil {
				return
			}
			packet = packet[size+2:]
		}
		return

	case naluType >= 6 && naluType <= 23: // other single NALU packet
	case naluType == 25: // STAB-B
	case naluType == 26: // MTAP-16
	case naluType == 27: // MTAP-24
	case naluType == 28: // FU-B

	default:
		err = fmt.Errorf("rtsp: unsupported H264 naluType=%d", naluType)
		return
	}

	return
}

func (self *Stream) handleRtpPacket(packet []byte) (err error) {
	if self.isCodecDataChange() {
		err = ErrCodecDataChange
		return
	}

	if self.client != nil && self.client.DebugRtp {
		fmt.Println("rtp: packet", self.CodecData.Type(), "len", len(packet))
		dumpsize := len(packet)
		if dumpsize > 32 {
			dumpsize = 32
		}
		fmt.Print(hex.Dump(packet[:dumpsize]))
	}

	/*
		0                   1                   2                   3
		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
		|V=2|P|X|  CC   |M|     PT      |       sequence number         |
		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
		|                           timestamp                           |
		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
		|           synchronization source (SSRC) identifier            |
		+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+
		|            contributing source (CSRC) identifiers             |
		|                             ....                              |
		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	*/
	if len(packet) < 8 {
		err = fmt.Errorf("rtp: packet too short")
		return
	}
	payloadOffset := 12 + int(packet[0]&0xf)*4
	if payloadOffset > len(packet) {
		err = fmt.Errorf("rtp: packet too short")
		return
	}
	timestamp := binary.BigEndian.Uint32(packet[4:8])
	payload := packet[payloadOffset:]

	/*
		PT 	Encoding Name 	Audio/Video (A/V) 	Clock Rate (Hz) 	Channels 	Reference
		0	PCMU	A	8000	1	[RFC3551]
		1	Reserved
		2	Reserved
		3	GSM	A	8000	1	[RFC3551]
		4	G723	A	8000	1	[Vineet_Kumar][RFC3551]
		5	DVI4	A	8000	1	[RFC3551]
		6	DVI4	A	16000	1	[RFC3551]
		7	LPC	A	8000	1	[RFC3551]
		8	PCMA	A	8000	1	[RFC3551]
		9	G722	A	8000	1	[RFC3551]
		10	L16	A	44100	2	[RFC3551]
		11	L16	A	44100	1	[RFC3551]
		12	QCELP	A	8000	1	[RFC3551]
		13	CN	A	8000	1	[RFC3389]
		14	MPA	A	90000		[RFC3551][RFC2250]
		15	G728	A	8000	1	[RFC3551]
		16	DVI4	A	11025	1	[Joseph_Di_Pol]
		17	DVI4	A	22050	1	[Joseph_Di_Pol]
		18	G729	A	8000	1	[RFC3551]
		19	Reserved	A
		20	Unassigned	A
		21	Unassigned	A
		22	Unassigned	A
		23	Unassigned	A
		24	Unassigned	V
		25	CelB	V	90000		[RFC2029]
		26	JPEG	V	90000		[RFC2435]
		27	Unassigned	V
		28	nv	V	90000		[RFC3551]
		29	Unassigned	V
		30	Unassigned	V
		31	H261	V	90000		[RFC4587]
		32	MPV	V	90000		[RFC2250]
		33	MP2T	AV	90000		[RFC2250]
		34	H263	V	90000		[Chunrong_Zhu]
		35-71	Unassigned	?
		72-76	Reserved for RTCP conflict avoidance				[RFC3551]
		77-95	Unassigned	?
		96-127	dynamic	?			[RFC3551]
	*/
	//payloadType := packet[1]&0x7f

	switch self.Sdp.Type {
	case av.H264:
		if err = self.handleH264Payload(timestamp, payload); err != nil {
			return
		}

	case av.AAC:
		if len(payload) < 4 {
			err = fmt.Errorf("rtp: aac packet too short")
			return
		}
		payload = payload[4:] // TODO: remove this hack
		self.gotpkt = true
		self.pkt.Data = payload
		self.timestamp = timestamp

	default:
		self.gotpkt = true
		self.pkt.Data = payload
		self.timestamp = timestamp
	}

	return
}

func (self *Client) Play() (err error) {
	req := Request{
		Method: "PLAY",
		Uri:    self.requestUri,
	}
	req.Header = append(req.Header, "Session: "+self.session)
	if err = self.WriteRequest(req); err != nil {
		return
	}

	if self.allCodecDataReady() {
		self.stage = stageCodecDataDone
	} else {
		self.stage = stageWaitCodecData
	}
	return
}

func (self *Client) Teardown() (err error) {
	req := Request{
		Method: "TEARDOWN",
		Uri:    self.requestUri,
	}
	req.Header = append(req.Header, "Session: "+self.session)
	if err = self.WriteRequest(req); err != nil {
		return
	}
	return
}

func (self *Client) Close() (err error) {
	return self.conn.Conn.Close()
}

func (self *Client) handleBlock(block []byte) (pkt av.Packet, ok bool, err error) {
	_, blockno, _ := self.parseBlockHeader(block)
	if blockno%2 != 0 {
		if self.DebugRtp {
			fmt.Println("rtsp: rtcp block len", len(block)-4)
		}
		return
	}

	i := blockno/2
	if i >= len(self.streams) {
		err = fmt.Errorf("rtsp: block no=%d invalid", blockno)
		return
	}
	stream := self.streams[i]

	herr := stream.handleRtpPacket(block[4:])
	if herr != nil {
		if !self.SkipErrRtpBlock {
			err = herr
			return
		}
	}

	if stream.gotpkt {
		/*
		TODO: sync AV by rtcp NTP timestamp
		TODO: handle timestamp overflow
		https://tools.ietf.org/html/rfc3550
		A receiver can then synchronize presentation of the audio and video packets by relating 
		their RTP timestamps using the timestamp pairs in RTCP SR packets.
		*/
		if stream.firsttimestamp == 0 {
			stream.firsttimestamp = stream.timestamp
		}
		stream.timestamp -= stream.firsttimestamp

		ok = true
		pkt = stream.pkt
		pkt.Time = time.Duration(stream.timestamp)*time.Second / time.Duration(stream.timeScale())
		pkt.Idx = int8(self.setupMap[i])

		if pkt.Time < stream.lasttime || pkt.Time - stream.lasttime > time.Minute*30 {
			err = fmt.Errorf("rtp: time invalid stream#%d time=%v lasttime=%v", pkt.Idx, pkt.Time, stream.lasttime)
			return
		}
		stream.lasttime = pkt.Time

		if self.DebugRtp {
			fmt.Println("rtp: pktout", pkt.Idx, pkt.Time, len(pkt.Data))
		}

		stream.pkt = av.Packet{}
		stream.gotpkt = false
	}

	return
}

func (self *Client) readPacket() (pkt av.Packet, err error) {
	if err = self.SendRtpKeepalive(); err != nil {
		return
	}

	for {
		var res Response
		for {
			if res, err = self.poll(); err != nil {
				return
			}
			if len(res.Block) > 0 {
				break
			}
		}

		var ok bool
		if pkt, ok, err = self.handleBlock(res.Block); err != nil {
			return
		}
		if ok {
			return
		}
	}

	return
}

func (self *Client) ReadPacket() (pkt av.Packet, err error) {
	if err = self.prepare(stageCodecDataDone); err != nil {
		return
	}
	return self.readPacket()
}

func Handler(h *avutil.RegisterHandler) {
	h.UrlDemuxer = func(uri string) (ok bool, demuxer av.DemuxCloser, err error) {
		if !strings.HasPrefix(uri, "rtsp://") {
			return
		}
		ok = true
		demuxer, err = Dial(uri)
		return
	}
}



================================================
FILE: format/rtsp/conn.go
================================================
package rtsp

import (
	"net"
	"time"
)

type connWithTimeout struct {
	Timeout time.Duration
	net.Conn
}

func (self connWithTimeout) Read(p []byte) (n int, err error) {
	if self.Timeout > 0 {
		self.Conn.SetReadDeadline(time.Now().Add(self.Timeout))
	}
	return self.Conn.Read(p)
}

func (self connWithTimeout) Write(p []byte) (n int, err error) {
	if self.Timeout > 0 {
		self.Conn.SetWriteDeadline(time.Now().Add(self.Timeout))
	}
	return self.Conn.Write(p)
}


================================================
FILE: format/rtsp/sdp/parser.go
================================================
package sdp

import (
	"encoding/base64"
	"encoding/hex"
	"fmt"
	"github.com/nareix/joy4/av"
	"strconv"
	"strings"
)

type Session struct {
	Uri string
}

type Media struct {
	AVType             string
	Type               av.CodecType
	TimeScale          int
	Control            string
	Rtpmap             int
	Config             []byte
	SpropParameterSets [][]byte
	PayloadType        int
	SizeLength         int
	IndexLength        int
}

func Parse(content string) (sess Session, medias []Media) {
	var media *Media

	for _, line := range strings.Split(content, "\n") {
		line = strings.TrimSpace(line)
		typeval := strings.SplitN(line, "=", 2)
		if len(typeval) == 2 {
			fields := strings.SplitN(typeval[1], " ", 2)

			switch typeval[0] {
			case "m":
				if len(fields) > 0 {
					switch fields[0] {
					case "audio", "video":
						medias = append(medias, Media{AVType: fields[0]})
						media = &medias[len(medias)-1]
						mfields := strings.Split(fields[1], " ")
						if len(mfields) >= 3 {
							media.PayloadType, _ = strconv.Atoi(mfields[2])
						}
					}
				}

			case "u":
				sess.Uri = typeval[1]

			case "a":
				if media != nil {
					for _, field := range fields {
						keyval := strings.SplitN(field, ":", 2)
						if len(keyval) >= 2 {
							key := keyval[0]
							val := keyval[1]
							switch key {
							case "control":
								media.Control = val
							case "rtpmap":
								media.Rtpmap, _ = strconv.Atoi(val)
							}
						}
						keyval = strings.Split(field, "/")
						if len(keyval) >= 2 {
							key := keyval[0]
							switch strings.ToUpper(key) {
							case "MPEG4-GENERIC":
								media.Type = av.AAC
							case "H264":
								media.Type = av.H264
							}
							if i, err := strconv.Atoi(keyval[1]); err == nil {
								media.TimeScale = i
							}
							if false {
								fmt.Println("sdp:", keyval[1], media.TimeScale)
							}
						}
						keyval = strings.Split(field, ";")
						if len(keyval) > 1 {
							for _, field := range keyval {
								keyval := strings.SplitN(field, "=", 2)
								if len(keyval) == 2 {
									key := strings.TrimSpace(keyval[0])
									val := keyval[1]
									switch key {
									case "config":
										media.Config, _ = hex.DecodeString(val)
									case "sizelength":
										media.SizeLength, _ = strconv.Atoi(val)
									case "indexlength":
										media.IndexLength, _ = strconv.Atoi(val)
									case "sprop-parameter-sets":
										fields := strings.Split(val, ",")
										for _, field := range fields {
											val, _ := base64.StdEncoding.DecodeString(field)
											media.SpropParameterSets = append(media.SpropParameterSets, val)
										}
									}
								}
							}
						}
					}
				}

			}
		}
	}
	return
}


================================================
FILE: format/rtsp/sdp/parser_test.go
================================================
package sdp

import (
	"testing"
)

func TestParse(t *testing.T) {
	infos := Decode(`
v=0
o=- 1459325504777324 1 IN IP4 192.168.0.123
s=RTSP/RTP stream from Network Video Server
i=mpeg4cif
t=0 0
a=tool:LIVE555 Streaming Media v2009.09.28
a=type:broadcast
a=control:*
a=range:npt=0-
a=x-qt-text-nam:RTSP/RTP stream from Network Video Server
a=x-qt-text-inf:mpeg4cif
m=video 0 RTP/AVP 96
c=IN IP4 0.0.0.0
b=AS:300
a=rtpmap:96 H264/90000
a=fmtp:96 profile-level-id=420029; packetization-mode=1; sprop-parameter-sets=Z00AHpWoKA9k,aO48gA==
a=x-dimensions: 720, 480
a=x-framerate: 15
a=control:track1
m=audio 0 RTP/AVP 96
c=IN IP4 0.0.0.0
b=AS:256
a=rtpmap:96 MPEG4-GENERIC/16000/2
a=fmtp:96 streamtype=5;profile-level-id=1;mode=AAC-hbr;sizelength=13;indexlength=3;indexdeltalength=3;config=1408
a=control:track2
m=audio 0 RTP/AVP 0
c=IN IP4 0.0.0.0
b=AS:50
a=recvonly
a=control:rtsp://109.195.127.207:554/mpeg4cif/trackID=2
a=rtpmap:0 PCMU/8000
a=Media_header:MEDIAINFO=494D4B48010100000400010010710110401F000000FA000000000000000000000000000000000000;
a=appversion:1.0
`)
	t.Logf("%v", infos)
}


================================================
FILE: format/rtsp/stream.go
================================================
package rtsp

import (
	"github.com/nareix/joy4/av"
	"github.com/nareix/joy4/format/rtsp/sdp"
	"time"
)

type Stream struct {
	av.CodecData
	Sdp    sdp.Media
	client *Client

	// h264
	fuStarted  bool
	fuBuffer   []byte
	sps        []byte
	pps        []byte
	spsChanged bool
	ppsChanged bool

	gotpkt    bool
	pkt       av.Packet
	timestamp uint32
	firsttimestamp uint32

	lasttime time.Duration
}



================================================
FILE: format/ts/demuxer.go
================================================
package ts

import (
	"bufio"
	"fmt"
	"time"
	"github.com/nareix/joy4/utils/bits/pio"
	"github.com/nareix/joy4/av"
	"github.com/nareix/joy4/format/ts/tsio"
	"github.com/nareix/joy4/codec/aacparser"
	"github.com/nareix/joy4/codec/h264parser"
	"io"
)

type Demuxer struct {
	r *bufio.Reader

	pkts []av.Packet

	pat     *tsio.PAT
	pmt     *tsio.PMT
	streams []*Stream
	tshdr   []byte

	stage int
}

func NewDemuxer(r io.Reader) *Demuxer {
	return &Demuxer{
		tshdr: make([]byte, 188),
		r: bufio.NewReaderSize(r, pio.RecommendBufioSize),
	}
}

func (self *Demuxer) Streams() (streams []av.CodecData, err error) {
	if err = self.probe(); err != nil {
		return
	}
	for _, stream := range self.streams {
		streams = append(streams, stream.CodecData)
	}
	return
}

func (self *Demuxer) probe() (err error) {
	if self.stage == 0 {
		for {
			if self.pmt != nil {
				n := 0
				for _, stream := range self.streams {
					if stream.CodecData != nil {
						n++
					}
				}
				if n == len(self.streams) {
					break
				}
			}
			if err = self.poll(); err != nil {
				return
			}
		}
		self.stage++
	}
	return
}

func (self *Demuxer) ReadPacket() (pkt av.Packet, err error) {
	if err = self.probe(); err != nil {
		return
	}

	for len(self.pkts) == 0 {
		if err = self.poll(); err != nil {
			return
		}
	}

	pkt = self.pkts[0]
	self.pkts = self.pkts[1:]
	return
}

func (self *Demuxer) poll() (err error) {
	if err = self.readTSPacket(); err == io.EOF {
		var n int
		if n, err = self.payloadEnd(); err != nil {
			return
		}
		if n == 0 {
			err = io.EOF
		}
	}
	return
}

func (self *Demuxer) initPMT(payload []byte) (err error) {
	var psihdrlen int
	var datalen int
	if _, _, psihdrlen, datalen, err = tsio.ParsePSI(payload); err != nil {
		return
	}
	self.pmt = &tsio.PMT{}
	if _, err = self.pmt.Unmarshal(payload[psihdrlen:psihdrlen+datalen]); err != nil {
		return
	}

	self.streams = []*Stream{}
	for i, info := range self.pmt.ElementaryStreamInfos {
		stream := &Stream{}
		stream.idx = i
		stream.demuxer = self
		stream.pid = info.ElementaryPID
		stream.streamType = info.StreamType
		switch info.StreamType {
		case tsio.ElementaryStreamTypeH264:
			self.streams = append(self.streams, stream)
		case tsio.ElementaryStreamTypeAdtsAAC:
			self.streams = append(self.streams, stream)
		}
	}
	return
}

func (self *Demuxer) payloadEnd() (n int, err error) {
	for _, stream := range self.streams {
		var i int
		if i, err = stream.payloadEnd(); err != nil {
			return
		}
		n += i
	}
	return
}

func (self *Demuxer) readTSPacket() (err error) {
	var hdrlen int
	var pid uint16
	var start bool
	var iskeyframe bool

	if _, err = io.ReadFull(self.r, self.tshdr); err != nil {
		return
	}

	if pid, start, iskeyframe, hdrlen, err = tsio.ParseTSHeader(self.tshdr); err != nil {
		return
	}
	payload := self.tshdr[hdrlen:]

	if self.pat == nil {
		if pid == 0 {
			var psihdrlen int
			var datalen int
			if _, _, psihdrlen, datalen, err = tsio.ParsePSI(payload); err != nil {
				return
			}
			self.pat = &tsio.PAT{}
			if _, err = self.pat.Unmarshal(payload[psihdrlen:psihdrlen+datalen]); err != nil {
				return
			}
		}
	} else if self.pmt == nil {
		for _, entry := range self.pat.Entries {
			if entry.ProgramMapPID == pid {
				if err = self.initPMT(payload); err != nil {
					return
				}
				break
			}
		}
	} else {
		for _, stream := range self.streams {
			if pid == stream.pid {
				if err = stream.handleTSPacket(start, iskeyframe, payload); err != nil {
					return
				}
				break
			}
		}
	}

	return
}

func (self *Stream) addPacket(payload []byte, timedelta time.Duration) {
	dts := self.dts
	pts := self.pts
	if dts == 0 {
		dts = pts
	}

	demuxer := self.demuxer
	pkt := av.Packet{
		Idx: int8(self.idx),
		IsKeyFrame: self.iskeyframe,
		Time: dts+timedelta,
		Data: payload,
	}
	if pts != dts {
		pkt.CompositionTime = pts-dts
	}
	demuxer.pkts = append(demuxer.pkts, pkt)
}

func (self *Stream) payloadEnd() (n int, err error) {
	payload := self.data
	if payload == nil {
		return
	}
	if self.datalen != 0 && len(payload) != self.datalen {
		err = fmt.Errorf("ts: packet size mismatch size=%d correct=%d", len(payload), self.datalen)
		return
	}
	self.data = nil

	switch self.streamType {
	case tsio.ElementaryStreamTypeAdtsAAC:
		var config aacparser.MPEG4AudioConfig

		delta := time.Duration(0)
		for len(payload) > 0 {
			var hdrlen, framelen, samples int
			if config, hdrlen, framelen, samples, err = aacparser.ParseADTSHeader(payload); err != nil {
				return
			}
			if self.CodecData == nil {
				if self.CodecData, err = aacparser.NewCodecDataFromMPEG4AudioConfig(config); err != nil {
					return
				}
			}
			self.addPacket(payload[hdrlen:framelen], delta)
			n++
			delta += time.Duration(samples) * time.Second / time.Duration(config.SampleRate)
			payload = payload[framelen:]
		}

	case tsio.ElementaryStreamTypeH264:
		nalus, _ := h264parser.SplitNALUs(payload)
		var sps, pps []byte
		for _, nalu := range nalus {
			if len(nalu) > 0 {
				naltype := nalu[0] & 0x1f
				switch {
				case naltype == 7:
					sps = nalu
				case naltype == 8:
					pps = nalu
				case h264parser.IsDataNALU(nalu):
					// raw nalu to avcc
					b := make([]byte, 4+len(nalu))
					pio.PutU32BE(b[0:4], uint32(len(nalu)))
					copy(b[4:], nalu)
					self.addPacket(b, time.Duration(0))
					n++
				}
			}
		}

		if self.CodecData == nil && len(sps) > 0 && len(pps) > 0 {
			if self.CodecData, err = h264parser.NewCodecDataFromSPSAndPPS(sps, pps); err != nil {
				return
			}
		}
	}

	return
}

func (self *Stream) handleTSPacket(start bool, iskeyframe bool, payload []byte) (err error) {
	if start {
		if _, err = self.payloadEnd(); err != nil {
			return
		}
		var hdrlen int
		if hdrlen, _, self.datalen, self.pts, self.dts, err = tsio.ParsePESHeader(payload); err != nil {
			return
		}
		self.iskeyframe = iskeyframe
		if self.datalen == 0 {
			self.data = make([]byte, 0, 4096)
		} else {
			self.data = make([]byte, 0, self.datalen)
		}
		self.data = append(self.data, payload[hdrlen:]...)
	} else {
		self.data = append(self.data, payload...)
	}
	return
}


================================================
FILE: format/ts/handler.go
================================================
package ts

import (
	"io"
	"github.com/nareix/joy4/av"
	"github.com/nareix/joy4/av/avutil"
)

func Handler(h *avutil.RegisterHandler) {
	h.Ext = ".ts"

	h.Probe = func(b []byte) bool {
		return b[0] == 0x47 && b[188] == 0x47
	}

	h.ReaderDemuxer = func(r io.Reader) av.Demuxer {
		return NewDemuxer(r)
	}

	h.WriterMuxer = func(w io.Writer) av.Muxer {
		return NewMuxer(w)
	}

	h.CodecTypes = CodecTypes
}



================================================
FILE: format/ts/muxer.go
================================================
package ts

import (
	"fmt"
	"github.com/nareix/joy4/av"
	"github.com/nareix/joy4/codec/aacparser"
	"github.com/nareix/joy4/codec/h264parser"
	"github.com/nareix/joy4/format/ts/tsio"
	"io"
	"time"
)

var CodecTypes = []av.CodecType{av.H264, av.AAC}

type Muxer struct {
	w                        io.Writer
	streams                  []*Stream
	PaddingToMakeCounterCont bool

	psidata []byte
	peshdr  []byte
	tshdr   []byte
	adtshdr []byte
	datav   [][]byte
	nalus   [][]byte

	tswpat, tswpmt *tsio.TSWriter
}

func NewMuxer(w io.Writer) *Muxer {
	return &Muxer{
		w:       w,
		psidata: make([]byte, 188),
		peshdr:  make([]byte, tsio.MaxPESHeaderLength),
		tshdr:   make([]byte, tsio.MaxTSHeaderLength),
		adtshdr: make([]byte, aacparser.ADTSHeaderLength),
		nalus:   make([][]byte, 16),
		datav:   make([][]byte, 16),
		tswpmt:  tsio.NewTSWriter(tsio.PMT_PID),
		tswpat:  tsio.NewTSWriter(tsio.PAT_PID),
	}
}

func (self *Muxer) newStream(codec av.CodecData) (err error) {
	ok := false
	for _, c := range CodecTypes {
		if codec.Type() == c {
			ok = true
			break
		}
	}
	if !ok {
		err = fmt.Errorf("ts: codec type=%s is not supported", codec.Type())
		return
	}

	pid := uint16(len(self.streams) + 0x100)
	stream := &Stream{
		muxer:     self,
		CodecData: codec,
		pid:       pid,
		tsw:       tsio.NewTSWriter(pid),
	}
	self.streams = append(self.streams, stream)
	return
}

func (self *Muxer) writePaddingTSPackets(tsw *tsio.TSWriter) (err error) {
	for tsw.ContinuityCounter&0xf != 0x0 {
		if err = tsw.WritePackets(self.w, self.datav[:0], 0, false, true); err != nil {
			return
		}
	}
	return
}

func (self *Muxer) WriteTrailer() (err error) {
	if self.PaddingToMakeCounterCont {
		for _, stream := range self.streams {
			if err = self.writePaddingTSPackets(stream.tsw); err != nil {
				return
			}
		}
	}
	return
}

func (self *Muxer) SetWriter(w io.Writer) {
	self.w = w
	return
}

func (self *Muxer) WritePATPMT() (err error) {
	pat := tsio.PAT{
		Entries: []tsio.PATEntry{
			{ProgramNumber: 1, ProgramMapPID: tsio.PMT_PID},
		},
	}
	patlen := pat.Marshal(self.psidata[tsio.PSIHeaderLength:])
	n := tsio.FillPSI(self.psidata, tsio.TableIdPAT, tsio.TableExtPAT, patlen)
	self.datav[0] = self.psidata[:n]
	if err = self.tswpat.WritePackets(self.w, self.datav[:1], 0, false, true); err != nil {
		return
	}

	var elemStreams []tsio.ElementaryStreamInfo
	for _, stream := range self.streams {
		switch stream.Type() {
		case av.AAC:
			elemStreams = append(elemStreams, tsio.ElementaryStreamInfo{
				StreamType:    tsio.ElementaryStreamTypeAdtsAAC,
				ElementaryPID: stream.pid,
			})
		case av.H264:
			elemStreams = append(elemStreams, tsio.ElementaryStreamInfo{
				StreamType:    tsio.ElementaryStreamTypeH264,
				ElementaryPID: stream.pid,
			})
		}
	}

	pmt := tsio.PMT{
		PCRPID:                0x100,
		ElementaryStreamInfos: elemStreams,
	}
	pmtlen := pmt.Len()
	if pmtlen+tsio.PSIHeaderLength > len(self.psidata) {
		err = fmt.Errorf("ts: pmt too large")
		return
	}
	pmt.Marshal(self.psidata[tsio.PSIHeaderLength:])
	n = tsio.FillPSI(self.psidata, tsio.TableIdPMT, tsio.TableExtPMT, pmtlen)
	self.datav[0] = self.psidata[:n]
	if err = self.tswpmt.WritePackets(self.w, self.datav[:1], 0, false, true); err != nil {
		return
	}

	return
}

func (self *Muxer) WriteHeader(streams []av.CodecData) (err error) {
	self.streams = []*Stream{}
	for _, stream := range streams {
		if err = self.newStream(stream); err != nil {
			return
		}
	}

	if err = self.WritePATPMT(); err != nil {
		return
	}
	return
}

func (self *Muxer) WritePacket(pkt av.Packet) (err error) {
	stream := self.streams[pkt.Idx]
	pkt.Time += time.Second

	switch stream.Type() {
	case av.AAC:
		codec := stream.CodecData.(aacparser.CodecData)

		n := tsio.FillPESHeader(self.peshdr, tsio.StreamIdAAC, len(self.adtshdr)+len(pkt.Data), pkt.Time, 0)
		self.datav[0] = self.peshdr[:n]
		aacparser.FillADTSHeader(self.adtshdr, codec.Config, 1024, len(pkt.Data))
		self.datav[1] = self.adtshdr
		self.datav[2] = pkt.Data

		if err = stream.tsw.WritePackets(self.w, self.datav[:3], pkt.Time, true, false); err != nil {
			return
		}

	case av.H264:
		codec := stream.CodecData.(h264parser.CodecData)

		nalus := self.nalus[:0]
		if pkt.IsKeyFrame {
			nalus = append(nalus, codec.SPS())
			nalus = append(nalus, codec.PPS())
		}
		pktnalus, _ := h264parser.SplitNALUs(pkt.Data)
		for _, nalu := range pktnalus {
			nalus = append(nalus, nalu)
		}

		datav := self.datav[:1]
		for i, nalu := range nalus {
			if i == 0 {
				datav = append(datav, h264parser.AUDBytes)
			} else {
				datav = append(datav, h264parser.StartCodeBytes)
			}
			datav = append(datav, nalu)
		}

		n := tsio.FillPESHeader(self.peshdr, tsio.StreamIdH264, -1, pkt.Time+pkt.CompositionTime, pkt.Time)
		datav[0] = self.peshdr[:n]

		if err = stream.tsw.WritePackets(self.w, datav, pkt.Time, pkt.IsKeyFrame, false); err != nil {
			return
		}
	}

	return
}


================================================
FILE: format/ts/stream.go
================================================
package ts

import (
	"time"
	"github.com/nareix/joy4/av"
	"github.com/nareix/joy4/format/ts/tsio"
)

type Stream struct {
	av.CodecData

	demuxer *Demuxer
	muxer   *Muxer

	pid    uint16
	streamId   uint8
	streamType uint8

	tsw       *tsio.TSWriter
	idx  int

	iskeyframe bool
	pts, dts time.Duration
	data []byte
	datalen int
}



================================================
FILE: format/ts/tsio/checksum.go
================================================
package tsio

var ieeeCrc32Tbl = []uint32{
	0x00000000, 0xB71DC104, 0x6E3B8209, 0xD926430D, 0xDC760413, 0x6B6BC517,
	0xB24D861A, 0x0550471E, 0xB8ED0826, 0x0FF0C922, 0xD6D68A2F, 0x61CB4B2B,
	0x649B0C35, 0xD386CD31, 0x0AA08E3C, 0xBDBD4F38, 0x70DB114C, 0xC7C6D048,
	0x1EE09345, 0xA9FD5241, 0xACAD155F, 0x1BB0D45B, 0xC2969756, 0x758B5652,
	0xC836196A, 0x7F2BD86E, 0xA60D9B63, 0x11105A67, 0x14401D79, 0xA35DDC7D,
	0x7A7B9F70, 0xCD665E74, 0xE0B62398, 0x57ABE29C, 0x8E8DA191, 0x39906095,
	0x3CC0278B, 0x8BDDE68F, 0x52FBA582, 0xE5E66486, 0x585B2BBE, 0xEF46EABA,
	0x3660A9B7, 0x817D68B3, 0x842D2FAD, 0x3330EEA9, 0xEA16ADA4, 0x5D0B6CA0,
	0x906D32D4, 0x2770F3D0, 0xFE56B0DD, 0x494B71D9, 0x4C1B36C7, 0xFB06F7C3,
	0x2220B4CE, 0x953D75CA, 0x28803AF2, 0x9F9DFBF6, 0x46BBB8FB, 0xF1A679FF,
	0xF4F63EE1, 0x43EBFFE5, 0x9ACDBCE8, 0x2DD07DEC, 0x77708634, 0xC06D4730,
	0x194B043D, 0xAE56C539, 0xAB068227, 0x1C1B4323, 0xC53D002E, 0x7220C12A,
	0xCF9D8E12, 0x78804F16, 0xA1A60C1B, 0x16BBCD1F, 0x13EB8A01, 0xA4F64B05,
	0x7DD00808, 0xCACDC90C, 0x07AB9778, 0xB0B6567C, 0x69901571, 0xDE8DD475,
	0xDBDD936B, 0x6CC0526F, 0xB5E61162, 0x02FBD066, 0xBF469F5E, 0x085B5E5A,
	0xD17D1D57, 0x6660DC53, 0x63309B4D, 0xD42D5A49, 0x0D0B1944, 0xBA16D840,
	0x97C6A5AC, 0x20DB64A8, 0xF9FD27A5, 0x4EE0E6A1, 0x4BB0A1BF, 0xFCAD60BB,
	0x258B23B6, 0x9296E2B2, 0x2F2BAD8A, 0x98366C8E, 0x41102F83, 0xF60DEE87,
	0xF35DA999, 0x4440689D, 0x9D662B90, 0x2A7BEA94, 0xE71DB4E0, 0x500075E4,
	0x892636E9, 0x3E3BF7ED, 0x3B6BB0F3, 0x8C7671F7, 0x555032FA, 0xE24DF3FE,
	0x5FF0BCC6, 0xE8ED7DC2, 0x31CB3ECF, 0x86D6FFCB, 0x8386B8D5, 0x349B79D1,
	0xEDBD3ADC, 0x5AA0FBD8, 0xEEE00C69, 0x59FDCD6D, 0x80DB8E60, 0x37C64F64,
	0x3296087A, 0x858BC97E, 0x5CAD8A73, 0xEBB04B77, 0x560D044F, 0xE110C54B,
	0x38368646, 0x8F2B4742, 0x8A7B005C, 0x3D66C158, 0xE4408255, 0x535D4351,
	0x9E3B1D25, 0x2926DC21, 0xF0009F2C, 0x471D5E28, 0x424D1936, 0xF550D832,
	0x2C769B3F, 0x9B6B5A3B, 0x26D61503, 0x91CBD407, 0x48ED970A, 0xFFF0560E,
	0xFAA01110, 0x4DBDD014, 0x949B9319, 0x2386521D, 0x0E562FF1, 0xB94BEEF5,
	0x606DADF8, 0xD7706CFC, 0xD2202BE2, 0x653DEAE6, 0xBC1BA9EB, 0x0B0668EF,
	0xB6BB27D7, 0x01A6E6D3, 0xD880A5DE, 0x6F9D64DA, 0x6ACD23C4, 0xDDD0E2C0,
	0x04F6A1CD, 0xB3EB60C9, 0x7E8D3EBD, 0xC990FFB9, 0x10B6BCB4, 0xA7AB7DB0,
	0xA2FB3AAE, 0x15E6FBAA, 0xCCC0B8A7, 0x7BDD79A3, 0xC660369B, 0x717DF79F,
	0xA85BB492, 0x1F467596, 0x1A163288, 0xAD0BF38C, 0x742DB081, 0xC3307185,
	0x99908A5D, 0x2E8D4B59, 0xF7AB0854, 0x40B6C950, 0x45E68E4E, 0xF2FB4F4A,
	0x2BDD0C47, 0x9CC0CD43, 0x217D827B, 0x9660437F, 0x4F460072, 0xF85BC176,
	0xFD0B8668, 0x4A16476C, 0x93300461, 0x242DC565, 0xE94B9B11, 0x5E565A15,
	0x87701918, 0x306DD81C, 0x353D9F02, 0x82205E06, 0x5B061D0B, 0xEC1BDC0F,
	0x51A69337, 0xE6BB5233, 0x3F9D113E, 0x8880D03A, 0x8DD09724, 0x3ACD5620,
	0xE3EB152D, 0x54F6D429, 0x7926A9C5, 0xCE3B68C1, 0x171D2BCC, 0xA000EAC8,
	0xA550ADD6, 0x124D6CD2, 0xCB6B2FDF, 0x7C76EEDB, 0xC1CBA1E3, 0x76D660E7,
	0xAFF023EA, 0x18EDE2EE, 0x1DBDA5F0, 0xAAA064F4, 0x738627F9, 0xC49BE6FD,
	0x09FDB889, 0xBEE0798D, 0x67C63A80, 0xD0DBFB84, 0xD58BBC9A, 0x62967D9E,
	0xBBB03E93, 0x0CADFF97, 0xB110B0AF, 0x060D71AB, 0xDF2B32A6, 0x6836F3A2,
	0x6D66B4BC, 0xDA7B75B8, 0x035D36B5, 0xB440F7B1, 0x00000001,
}

func calcCRC32(crc uint32, data []byte) uint32 {
	for _, b := range data {
		crc = ieeeCrc32Tbl[b^byte(crc)] ^ (crc >> 8)
	}
	return crc
}



================================================
FILE: format/ts/tsio/tsio.go
================================================

package tsio

import (
	"io"
	"time"
	"fmt"
	"github.com/nareix/joy4/utils/bits/pio"
)

const (
	StreamIdH264 = 0xe0
	StreamIdAAC  = 0xc0
)

const (
	PAT_PID = 0
	PMT_PID = 0x1000
)

const TableIdPMT = 2
const TableExtPMT = 1

const TableIdPAT = 0
const TableExtPAT = 1

const MaxPESHeaderLength = 19
const MaxTSHeaderLength = 12

var ErrPESHeader = fmt.Errorf("invalid PES header")
var ErrPSIHeader = fmt.Errorf("invalid PSI header")
var ErrParsePMT = fmt.Errorf("invalid PMT")
var ErrParsePAT = fmt.Errorf("invalid PAT")

const (
	ElementaryStreamTypeH264    = 0x1B
	ElementaryStreamTypeAdtsAAC = 0x0F
)

type PATEntry struct {
	ProgramNumber uint16
	NetworkPID    uint16
	ProgramMapPID uint16
}

type PAT struct {
	Entries []PATEntry
}

func (self PAT) Len() (n int) {
	return len(self.Entries)*4
}

func (self PAT) Marshal(b []byte) (n int) {
	for _, entry := range self.Entries {
		pio.PutU16BE(b[n:], entry.ProgramNumber)
		n += 2
		if entry.ProgramNumber == 0 {
			pio.PutU16BE(b[n:], entry.NetworkPID&0x1fff|7<<13)
			n += 2
		} else {
			pio.PutU16BE(b[n:], entry.ProgramMapPID&0x1fff|7<<13)
			n += 2
		}
	}
	return
}

func (self *PAT) Unmarshal(b []byte) (n int, err error) {
	for n < len(b) {
		if n+4 <= len(b) {
			var entry PATEntry
			entry.ProgramNumber = pio.U16BE(b[n:])
			n += 2
			if entry.ProgramNumber == 0 {
				entry.NetworkPID = pio.U16BE(b[n:])&0x1fff
				n += 2
			} else {
				entry.ProgramMapPID = pio.U16BE(b[n:])&0x1fff
				n += 2
			}
			self.Entries = append(self.Entries, entry)
		} else {
			break
		}
	}
	if n < len(b) {
		err = ErrParsePAT
		return
	}
	return
}

type Descriptor struct {
	Tag  uint8
	Data []byte
}

type ElementaryStreamInfo struct {
	StreamType    uint8
	ElementaryPID uint16
	Descriptors   []Descriptor
}

type PMT struct {
	PCRPID                uint16
	ProgramDescriptors    []Descriptor
	ElementaryStreamInfos []ElementaryStreamInfo
}

func (self PMT) Len() (n int) {
	// 111(3)
	// PCRPID(13)
	n += 2

	// desclen(16)
	n += 2

	for _, desc := range self.ProgramDescriptors {
		n += 2+len(desc.Data)
	}

	for _, info := range self.ElementaryStreamInfos {
		// streamType
		n += 1

		// Reserved(3)
		// Elementary PID(13)
		n += 2

		// Reserved(6)
		// ES Info length length(10)
		n += 2

		for _, desc := range info.Descriptors {
			n += 2+len(desc.Data)
		}
	}

	return
}

func (self PMT) fillDescs(b []byte, descs []Descriptor) (n int) {
	for _, desc := range descs {
		b[n] = desc.Tag
		n++
		b[n] = uint8(len(desc.Data))
		n++
		copy(b[n:], desc.Data)
		n += len(desc.Data)
	}
	return
}

func (self PMT) Marshal(b []byte) (n int) {
	// 111(3)
	// PCRPID(13)
	pio.PutU16BE(b[n:], self.PCRPID|7<<13)
	n += 2

	hold := n
	n += 2
	pos := n
	n += self.fillDescs(b[n:], self.ProgramDescriptors)
	desclen := n-pos
	pio.PutU16BE(b[hold:], uint16(desclen)|0xf<<12)

	for _, info := range self.ElementaryStreamInfos {
		b[n] = info.StreamType
		n++

		// Reserved(3)
		// Elementary PID(13)
		pio.PutU16BE(b[n:], info.ElementaryPID|7<<13)
		n += 2

		hold := n
		n += 2
		pos := n
		n += self.fillDescs(b[n:], info.Descriptors)
		desclen := n-pos
		pio.PutU16BE(b[hold:], uint16(desclen)|0x3c<<10)
	}

	return
}

func (self PMT) parseDescs(b []byte) (descs []Descriptor, err error) {
	n := 0
	for n < len(b) {
		if n+2 <= len(b) {
			desc := Descriptor{}
			desc.Tag = b[n]
			desc.Data = make([]byte, b[n+1])
			n += 2
			if n+len(desc.Data) < len(b) {
				copy(desc.Data, b[n:])
				descs = append(descs, desc)
				n += len(desc.Data)
			} else {
				break
			}
		} else {
			break
		}
	}
	if n < len(b) {
		err = ErrParsePMT
		return
	}
	return
}

func (self *PMT) Unmarshal(b []byte) (n int, err error) {
	if len(b) < n+4 {
		err = ErrParsePMT
		return
	}

	// 111(3)
	// PCRPID(13)
	self.PCRPID = pio.U16BE(b[0:2])&0x1fff
	n += 2

	// Reserved(4)=0xf
	// Reserved(2)=0x0
	// Program info length(10)
	desclen := int(pio.U16BE(b[2:4])&0x3ff)
	n += 2

	if desclen > 0 {
		if len(b) < n+desclen {
			err = ErrParsePMT
			return
		}
		if self.ProgramDescriptors, err = self.parseDescs(b[n:n+desclen]); err != nil {
			return
		}
		n += desclen
	}

	for n < len(b) {
		if len(b) < n+5 {
			err = ErrParsePMT
			return
		}

		var info ElementaryStreamInfo
		info.StreamType = b[n]
		n++

		// Reserved(3)
		// Elementary PID(13)
		info.ElementaryPID = pio.U16BE(b[n:])&0x1fff
		n += 2

		// Reserved(6)
		// ES Info length(10)
		desclen := int(pio.U16BE(b[n:])&0x3ff)
		n += 2

		if desclen > 0 {
			if len(b) < n+desclen {
				err = ErrParsePMT
				return
			}
			if info.Descriptors, err = self.parseDescs(b[n:n+desclen]); err != nil {
				return
			}
			n += desclen
		}

		self.ElementaryStreamInfos = append(self.ElementaryStreamInfos, info)
	}

	return
}

func ParsePSI(h []byte) (tableid uint8, tableext uint16, hdrlen int, datalen int, err error) {
	if len(h) < 8 {
		err = ErrPSIHeader
		return
	}

	// pointer(8)
	pointer := h[0]
	hdrlen++
	if pointer > 0 {
		hdrlen += int(pointer)
		if len(h) < hdrlen {
			err = ErrPSIHeader
			return
		}
	}

	if len(h) < hdrlen+12 {
		err = ErrPSIHeader
		return
	}

	// table_id(8)
	tableid = h[hdrlen]
	hdrlen++

	// section_syntax_indicator(1)=1,private_bit(1)=0,reserved(2)=3,unused(2)=0,section_length(10)
	datalen = int(pio.U16BE(h[hdrlen:]))&0x3ff - 9
	hdrlen += 2

	if datalen < 0 {
		err = ErrPSIHeader
		return
	}

	// Table ID extension(16)
	tableext = pio.U16BE(h[hdrlen:])
	hdrlen += 2

	// resverd(2)=3
	// version(5)
	// Current_next_indicator(1)
	hdrlen++

	// section_number(8)
	hdrlen++

	// last_section_number(8)
	hdrlen++

	// data

	// crc(32)

	return
}

const PSIHeaderLength = 9

func FillPSI(h []byte, tableid uint8, tableext uint16, datalen int) (n int) {
	// pointer(8)
	h[n] = 0
	n++

	// table_id(8)
	h[n] = tableid
	n++

	// section_syntax_indicator(1)=1,private_bit(1)=0,reserved(2)=3,unused(2)=0,section_length(10)
	pio.PutU16BE(h[n:], uint16(0xa<<12 | 2+3+4+datalen))
	n += 2

	// Table ID extension(16)
	pio.PutU16BE(h[n:], tableext)
	n += 2

	// resverd(2)=3,version(5)=0,Current_next_indicator(1)=1
	h[n] = 0x3<<6 | 1
	n++

	// section_number(8)
	h[n] = 0
	n++

	// last_section_number(8)
	h[n] = 0
	n++

	n += datalen

	crc := calcCRC32(0xffffffff, h[1:n])
	pio.PutU32LE(h[n:], crc)
	n += 4

	return
}

func TimeToPCR(tm time.Duration) (pcr uint64) {
	// base(33)+resverd(6)+ext(9)
	ts := uint64(tm*PCR_HZ/time.Second)
	base := ts / 300
	ext := ts % 300
	pcr = base<<15 | 0x3f<<9 | ext
	return
}

func PCRToTime(pcr uint64) (tm time.Duration) {
	base := pcr >> 15
	ext := pcr & 0x1ff
	ts := base*300 + ext
	tm = time.Duration(ts)*time.Second/time.Duration(PCR_HZ)
	return
}

func TimeToTs(tm time.Duration) (v uint64) {
	ts := uint64(tm*PTS_HZ/time.Second)
	// 0010	PTS 32..30 1	PTS 29..15 1 PTS 14..00 1
	v = ((ts>>30)&0x7)<<33 | ((ts>>15)&0x7fff)<<17 | (ts&0x7fff)<<1 | 0x100010001
	return
}

func TsToTime(v uint64) (tm time.Duration) {
	// 0010	PTS 32..30 1	PTS 29..15 1 PTS 14..00 1
	ts := (((v>>33)&0x7)<<30) | (((v>>17)&0x7fff) << 15) | ((v>>1)&0x7fff)
	tm = time.Duration(ts)*time.Second/time.Duration(PTS_HZ)
	return
}

const (
	PTS_HZ = 90000
	PCR_HZ = 27000000
)

func ParsePESHeader(h []byte) (hdrlen int, streamid uint8, datalen int, pts, dts time.Duration, err error) {
	if h[0] != 0 || h[1] != 0 || h[2] != 1 {
		err = ErrPESHeader
		return
	}
	streamid = h[3]

	flags := h[7]
	hdrlen = int(h[8])+9

	datalen = int(pio.U16BE(h[4:6]))
	if datalen > 0 {
		datalen -= int(h[8])+3
	}

	const PTS = 1 << 7
	const DTS = 1 << 6

	if flags&PTS != 0 {
		if len(h) < 14 {
			err = ErrPESHeader
			return
		}
		pts = TsToTime(pio.U40BE(h[9:14]))
		if flags&DTS != 0 {
			if len(h) < 19 {
				err = ErrPESHeader
				return
			}
			dts = TsToTime(pio.U40BE(h[14:19]))
		}
	}

	return
}

func FillPESHeader(h []byte, streamid uint8, datalen int, pts, dts time.Duration) (n int) {
	h[0] = 0
	h[1] = 0
	h[2] = 1
	h[3] = streamid

	const PTS = 1 << 7
	const DTS = 1 << 6

	var flags uint8
	if pts != 0 {
		flags |= PTS
		if dts != 0 {
			flags |= DTS
		}
	}

	if flags&PTS != 0 {
		n += 5
	}
	if flags&DTS != 0 {
		n += 5
	}

	// packet_length(16) if zero then variable length
	// Specifies the number of bytes remaining in the packet after this field. Can be zero.
	// If the PES packet length is set to zero, the PES packet can be of any length.
	// A value of zero for the PES packet length can be used only when the PES packet payload is a **video** elementary stream.
	var pktlen uint16
	if datalen >= 0 {
		pktlen = uint16(datalen + n + 3)
	}
	pio.PutU16BE(h[4:6], pktlen)

	h[6] = 2<<6|1 // resverd(6,2)=2,original_or_copy(0,1)=1
	h[7] = flags
	h[8] = uint8(n)

	// pts(40)?
	// dts(40)?
	if flags&PTS != 0 {
		if flags&DTS != 0 {
			pio.PutU40BE(h[9:14], TimeToTs(pts)|3<<36)
			pio.PutU40BE(h[14:19], TimeToTs(dts)|1<<36)
		} else {
			pio.PutU40BE(h[9:14], TimeToTs(pts)|2<<36)
		}
	}

	n += 9
	return
}

type TSWriter struct {
	w   io.Writer
	ContinuityCounter uint
	tshdr []byte
}

func NewTSWriter(pid uint16) *TSWriter {
	w := &TSWriter{}
	w.tshdr = make([]byte, 188)
	w.tshdr[0] = 0x47
	pio.PutU16BE(w.tshdr[1:3], pid&0x1fff)
	for i := 6; i < 188; i++ {
		w.tshdr[i] = 0xff
	}
	return w
}

func (self *TSWriter) WritePackets(w io.Writer, datav [][]byte, pcr time.Duration, sync bool, paddata bool) (err error) {
	datavlen := pio.VecLen(datav)
	writev := make([][]byte, len(datav))
	writepos := 0

	for writepos < datavlen {
		self.tshdr[1] = self.tshdr[1]&0x1f
		self.tshdr[3] = byte(self.ContinuityCounter)&0xf|0x30
		self.tshdr[5] = 0 // flags
		hdrlen := 6
		self.ContinuityCounter++

		if writepos == 0 {
			self.tshdr[1] = 0x40|self.tshdr[1] // Payload Unit Start Indicator
			if pcr != 0 {
				hdrlen += 6
				self.tshdr[5] = 0x10|self.tshdr[5] // PCR flag (Discontinuity indicator 0x80)
				pio.PutU48BE(self.tshdr[6:12], TimeToPCR(pcr))
			}
			if sync {
				self.tshdr[5] = 0x40|self.tshdr[5] // Random Access indicator
			}
		}

		padtail := 0
		end := writepos + 188 - hdrlen
		if end > datavlen {
			if paddata {
				padtail = end - datavlen
			} else {
				hdrlen += end - datavlen
			}
			end = datavlen
		}
		n := pio.VecSliceTo(datav, writev, writepos, end)

		self.tshdr[4] = byte(hdrlen)-5 // length
		if _, err = w.Write(self.tshdr[:hdrlen]); err != nil {
			return
		}
		for i := 0; i < n; i++ {
			if _, err = w.Write(writev[i]); err != nil {
				return
			}
		}
		if padtail > 0 {
			if _, err = w.Write(self.tshdr[188-padtail:188]); err != nil {
				return
			}
		}

		writepos = end
	}

	return
}

func ParseTSHeader(tshdr []byte) (pid uint16, start bool, iskeyframe bool, hdrlen int, err error) {
	// https://en.wikipedia.org/wiki/MPEG_transport_stream
	if tshdr[0] != 0x47 {
		err = fmt.Errorf("tshdr sync invalid")
		return
	}
	pid = uint16((tshdr[1]&0x1f))<<8|uint16(tshdr[2])
	start = tshdr[1]&0x40 != 0
	hdrlen += 4
	if tshdr[3]&0x20 != 0 {
		hdrlen += int(tshdr[4])+1
		iskeyframe = tshdr[5]&0x40 != 0
	}
	return
}



================================================
FILE: utils/bits/bits.go
================================================
package bits

import (
	"io"
)

type Reader struct {
	R    io.Reader
	n    int
	bits uint64
}

func (self *Reader) ReadBits64(n int) (bits uint64, err error) {
	if self.n < n {
		var b [8]byte
		var got int
		want := (n - self.n + 7) / 8
		if got, err = self.R.Read(b[:want]); err != nil {
			return
		}
		if got < want {
			err = io.EOF
			return
		}
		for i := 0; i < got; i++ {
			self.bits <<= 8
			self.bits |= uint64(b[i])
		}
		self.n += got * 8
	}
	bits = self.bits >> uint(self.n-n)
	self.bits ^= bits << uint(self.n-n)
	self.n -= n
	return
}

func (self *Reader) ReadBits(n int) (bits uint, err error) {
	var bits64 uint64
	if bits64, err = self.ReadBits64(n); err != nil {
		return
	}
	bits = uint(bits64)
	return
}

func (self *Reader) Read(p []byte) (n int, err error) {
	for n < len(p) {
		want := 8
		if len(p)-n < want {
			want = len(p) - n
		}
		var bits uint64
		if bits, err = self.ReadBits64(want * 8); err != nil {
			break
		}
		for i := 0; i < want; i++ {
			p[n+i] = byte(bits >> uint((want-i-1)*8))
		}
		n += want
	}
	return
}

type Writer struct {
	W    io.Writer
	n    int
	bits uint64
}

func (self *Writer) WriteBits64(bits uint64, n int) (err error) {
	if self.n+n > 64 {
		move := uint(64 - self.n)
		mask := bits >> move
		self.bits = (self.bits << move) | mask
		self.n = 64
		if err = self.FlushBits(); err != nil {
			return
		}
		n -= int(move)
		bits ^= (mask << move)
	}
	self.bits = (self.bits << uint(n)) | bits
	self.n += n
	return
}

func (self *Writer) WriteBits(bits uint, n int) (err error) {
	return self.WriteBits64(uint64(bits), n)
}

func (self *Writer) Write(p []byte) (n int, err error) {
	for n < len(p) {
		if err = self.WriteBits64(uint64(p[n]), 8); err != nil {
			return
		}
		n++
	}
	return
}

func (self *Writer) FlushBits() (err error) {
	if self.n > 0 {
		var b [8]byte
		bits := self.bits
		if self.n%8 != 0 {
			bits <<= uint(8 - (self.n % 8))
		}
		want := (self.n + 7) / 8
		for i := 0; i < want; i++ {
			b[i] = byte(bits >> uint((want-i-1)*8))
		}
		if _, err = self.W.Write(b[:want]); err != nil {
			return
		}
		self.n = 0
	}
	return
}


================================================
FILE: utils/bits/bits_test.go
================================================
package bits

import (
	"bytes"
	"testing"
)

func TestBits(t *testing.T) {
	rdata := []byte{0xf3, 0xb3, 0x45, 0x60}
	rbuf := bytes.NewReader(rdata[:])
	r := &Reader{R: rbuf}
	var u32 uint
	if u32, _ = r.ReadBits(4); u32 != 0xf {
		t.FailNow()
	}
	if u32, _ = r.ReadBits(4); u32 != 0x3 {
		t.FailNow()
	}
	if u32, _ = r.ReadBits(2); u32 != 0x2 {
		t.FailNow()
	}
	if u32, _ = r.ReadBits(2); u32 != 0x3 {
		t.FailNow()
	}
	b := make([]byte, 2)
	if r.Read(b); b[0] != 0x34 || b[1] != 0x56 {
		t.FailNow()
	}

	wbuf := &bytes.Buffer{}
	w := &Writer{W: wbuf}
	w.WriteBits(0xf, 4)
	w.WriteBits(0x3, 4)
	w.WriteBits(0x2, 2)
	w.WriteBits(0x3, 2)
	n, _ := w.Write([]byte{0x34, 0x56})
	if n != 2 {
		t.FailNow()
	}
	w.FlushBits()
	wdata := wbuf.Bytes()
	if wdata[0] != 0xf3 || wdata[1] != 0xb3 || wdata[2] != 0x45 || wdata[3] != 0x60 {
		t.FailNow()
	}

	b = make([]byte, 8)
	PutUInt64BE(b, 0x11223344, 32)
	if b[0] != 0x11 || b[1] != 0x22 || b[2] != 0x33 || b[3] != 0x44 {
		t.FailNow()
	}
}


================================================
FILE: utils/bits/bufio/bufio.go
================================================
package bufio

import (
	"io"
)

type Reader struct {
	buf [][]byte
	R io.ReadSeeker
}

func NewReaderSize(r io.ReadSeeker, size int) *Reader {
	buf := make([]byte, size*2)
	return &Reader{
		R: r,
		buf: [][]byte{buf[0:size], buf[size:]},
	}
}

func (self *Reader) ReadAt(b []byte, off int64) (n int, err error) {
	return
}



================================================
FILE: utils/bits/golomb_reader.go
================================================
package bits

import (
	"io"
)

type GolombBitReader struct {
	R    io.Reader
	buf  [1]byte
	left byte
}

func (self *GolombBitReader) ReadBit() (res uint, err error) {
	if self.left == 0 {
		if _, err = self.R.Read(self.buf[:]); err != nil {
			return
		}
		self.left = 8
	}
	self.left--
	res = uint(self.buf[0]>>self.left) & 1
	return
}

func (self *GolombBitReader) ReadBits(n int) (res uint, err error) {
	for i := 0; i < n; i++ {
		var bit uint
		if bit, err = self.ReadBit(); err != nil {
			return
		}
		res |= bit << uint(n-i-1)
	}
	return
}

func (self *GolombBitReader) ReadExponentialGolombCode() (res uint, err error) {
	i := 0
	for {
		var bit uint
		if bit, err = self.ReadBit(); err != nil {
			return
		}
		if !(bit == 0 && i < 32) {
			break
		}
		i++
	}
	if res, err = self.ReadBits(i); err != nil {
		return
	}
	res += (1 << uint(i)) - 1
	return
}

func (self *GolombBitReader) ReadSE() (res uint, err error) {
	if res, err = self.ReadExponentialGolombCode(); err != nil {
		return
	}
	if res&0x01 != 0 {
		res = (res + 1) / 2
	} else {
		res = -res / 2
	}
	return
}


================================================
FILE: utils/bits/pio/pio.go
================================================

package pio

var RecommendBufioSize = 1024*64



================================================
FILE: utils/bits/pio/reader.go
================================================

package pio

func U8(b []byte) (i uint8) {
	return b[0]
}

func U16BE(b []byte) (i uint16) {
	i = uint16(b[0])
	i <<= 8; i |= uint16(b[1])
	return
}

func I16BE(b []byte) (i int16) {
	i = int16(b[0])
	i <<= 8; i |= int16(b[1])
	return
}

func I24BE(b []byte) (i int32) {
	i = int32(int8(b[0]))
	i <<= 8; i |= int32(b[1])
	i <<= 8; i |= int32(b[2])
	return
}

func U24BE(b []byte) (i uint32) {
	i = uint32(b[0])
	i <<= 8; i |= uint32(b[1])
	i <<= 8; i |= uint32(b[2])
	return
}

func I32BE(b []byte) (i int32) {
	i = int32(int8(b[0]))
	i <<= 8; i |= int32(b[1])
	i <<= 8; i |= int32(b[2])
	i <<= 8; i |= int32(b[3])
	return
}

func U32LE(b []byte) (i uint32) {
	i = uint32(b[3])
	i <<= 8; i |= uint32(b[2])
	i <<= 8; i |= uint32(b[1])
	i <<= 8; i |= uint32(b[0])
	return
}

func U32BE(b []byte) (i uint32) {
	i = uint32(b[0])
	i <<= 8; i |= uint32(b[1])
	i <<= 8; i |= uint32(b[2])
	i <<= 8; i |= uint32(b[3])
	return
}

func U40BE(b []byte) (i uint64) {
	i = uint64(b[0])
	i <<= 8; i |= uint64(b[1])
	i <<= 8; i |= uint64(b[2])
	i <<= 8; i |= uint64(b[3])
	i <<= 8; i |= uint64(b[4])
	return
}

func U64BE(b []byte) (i uint64) {
	i = uint64(b[0])
	i <<= 8; i |= uint64(b[1])
	i <<= 8; i |= uint64(b[2])
	i <<= 8; i |= uint64(b[3])
	i <<= 8; i |= uint64(b[4])
	i <<= 8; i |= uint64(b[5])
	i <<= 8; i |= uint64(b[6])
	i <<= 8; i |= uint64(b[7])
	return
}

func I64BE(b []byte) (i int64) {
	i = int64(int8(b[0]))
	i <<= 8; i |= int64(b[1])
	i <<= 8; i |= int64(b[2])
	i <<= 8; i |= int64(b[3])
	i <<= 8; i |= int64(b[4])
	i <<= 8; i |= int64(b[5])
	i <<= 8; i |= int64(b[6])
	i <<= 8; i |= int64(b[7])
	return
}




================================================
FILE: utils/bits/pio/vec.go
================================================
package pio

func VecLen(vec [][]byte) (n int) {
	for _, b := range vec {
		n += len(b)
	}
	return
}

func VecSliceTo(in [][]byte, out [][]byte, s int, e int) (n int) {
	if s < 0 {
		s = 0
	}

	if e >= 0 && e < s {
		panic("pio: VecSlice start > end")
	}

	i := 0
	off := 0
	for s > 0 && i < len(in) {
		left := len(in[i])
		read := s
		if left < read {
			read = left
		}
		left -= read
		off += read
		s -= read
		e -= read
		if left == 0 {
			i++
			off = 0
		}
	}
	if s > 0 {
		panic("pio: VecSlice start out of range")
	}

	for e != 0 && i < len(in) {
		left := len(in[i])-off
		read := left
		if e > 0 && e < read {
			read = e
		}
		out[n] = in[i][off:off+read]
		n++
		left -= read
		e -= read
		off += read
		if left == 0 {
			i++
			off = 0
		}
	}
	if e > 0 {
		panic("pio: VecSlice end out of range")
	}

	return
}

func VecSlice(in [][]byte, s int, e int) (out [][]byte) {
	out = make([][]byte, len(in))
	n := VecSliceTo(in, out, s, e)
	out = out[:n]
	return
}



================================================
FILE: utils/bits/pio/vec_test.go
================================================

package pio

import (
	"fmt"
)

func ExampleVec() {
	vec := [][]byte{[]byte{1,2,3}, []byte{4,5,6,7,8,9}, []byte{10,11,12,13}}
	println(VecLen(vec))

	vec = VecSlice(vec, 1, -1)
	fmt.Println(vec)

	vec = VecSlice(vec, 2, -1)
	fmt.Println(vec)

	vec = VecSlice(vec, 8, 8)
	fmt.Println(vec)

	// Output:
}


================================================
FILE: utils/bits/pio/writer.go
================================================

package pio

func PutU8(b []byte, v uint8) {
	b[0] = v
}

func PutI16BE(b []byte, v int16) {
	b[0] = byte(v>>8)
	b[1] = byte(v)
}

func PutU16BE(b []byte, v uint16) {
	b[0] = byte(v>>8)
	b[1] = byte(v)
}

func PutI24BE(b []byte, v int32) {
	b[0] = byte(v>>16)
	b[1] = byte(v>>8)
	b[2] = byte(v)
}

func PutU24BE(b []byte, v uint32) {
	b[0] = byte(v>>16)
	b[1] = byte(v>>8)
	b[2] = byte(v)
}

func PutI32BE(b []byte, v int32) {
	b[0] = byte(v>>24)
	b[1] = byte(v>>16)
	b[2] = byte(v>>8)
	b[3] = byte(v)
}

func PutU32BE(b []byte, v uint32) {
	b[0] = byte(v>>24)
	b[1] = byte(v>>16)
	b[2] = byte(v>>8)
	b[3] = byte(v)
}

func PutU32LE(b []byte, v uint32) {
	b[3] = byte(v>>24)
	b[2] = byte(v>>16)
	b[1] = byte(v>>8)
	b[0] = byte(v)
}

func PutU40BE(b []byte, v uint64) {
	b[0] = byte(v>>32)
	b[1] = byte(v>>24)
	b[2] = byte(v>>16)
	b[3] = byte(v>>8)
	b[4] = byte(v)
}

func PutU48BE(b []byte, v uint64) {
	b[0] = byte(v>>40)
	b[1] = byte(v>>32)
	b[2] = byte(v>>24)
	b[3] = byte(v>>16)
	b[4] = byte(v>>8)
	b[5] = byte(v)
}

func PutU64BE(b []byte, v uint64) {
	b[0] = byte(v>>56)
	b[1] = byte(v>>48)
	b[2] = byte(v>>40)
	b[3] = byte(v>>32)
	b[4] = byte(v>>24)
	b[5] = byte(v>>16)
	b[6] = byte(v>>8)
	b[7] = byte(v)
}

func PutI64BE(b []byte, v int64) {
	b[0] = byte(v>>56)
	b[1] = byte(v>>48)
	b[2] = byte(v>>40)
	b[3] = byte(v>>32)
	b[4] = byte(v>>24)
	b[5] = byte(v>>16)
	b[6] = byte(v>>8)
	b[7] = byte(v)
}