Showing preview only (1,426K chars total). Download the full file or copy to clipboard to get everything.
Repository: julienr/libpng-android
Branch: master
Commit: 8bf331e403da
Files: 38
Total size: 1.4 MB
Directory structure:
gitextract_0ngj2ibb/
├── .gitattributes
├── .gitignore
├── CMakeLists.txt
├── LICENSE
├── README.rst
├── build.sh
├── jni/
│ ├── Android.mk
│ ├── Application.mk
│ ├── arm/
│ │ ├── arm_init.c
│ │ ├── filter_neon.S
│ │ ├── filter_neon_intrinsics.c
│ │ └── palette_neon_intrinsics.c
│ ├── config.h
│ ├── example.c
│ ├── png.c
│ ├── png.h
│ ├── pngconf.h
│ ├── pngdebug.h
│ ├── pngerror.c
│ ├── pngget.c
│ ├── pnginfo.h
│ ├── pnglibconf.h
│ ├── pngmem.c
│ ├── pngpread.c
│ ├── pngpriv.h
│ ├── pngread.c
│ ├── pngrio.c
│ ├── pngrtran.c
│ ├── pngrutil.c
│ ├── pngset.c
│ ├── pngstruct.h
│ ├── pngtest.c
│ ├── pngtrans.c
│ ├── pngwio.c
│ ├── pngwrite.c
│ ├── pngwtran.c
│ └── pngwutil.c
└── png-config.cmake.in
================================================
FILE CONTENTS
================================================
================================================
FILE: .gitattributes
================================================
* text=auto
================================================
FILE: .gitignore
================================================
.DS_Store
obj
================================================
FILE: CMakeLists.txt
================================================
cmake_minimum_required( VERSION 3.6 )
set( project_name png )
project( ${project_name} )
if( MSVC )
add_definitions(/MP)
endif()
set( source_dir ${CMAKE_CURRENT_SOURCE_DIR}/jni )
set( headers
${source_dir}/pnginfo.h
${source_dir}/config.h
${source_dir}/png.h
${source_dir}/pngconf.h
${source_dir}/pngdebug.h
${source_dir}/pnglibconf.h
${source_dir}/pngpriv.h
${source_dir}/pngstruct.h
)
set( sources
${source_dir}/arm/arm_init.c
${source_dir}/arm/filter_neon.S
${source_dir}/arm/filter_neon_intrinsics.c
${source_dir}/png.c
${source_dir}/pngerror.c
${source_dir}/pngget.c
${source_dir}/pngmem.c
${source_dir}/pngpread.c
${source_dir}/pngread.c
${source_dir}/pngrio.c
${source_dir}/pngrtran.c
${source_dir}/pngrutil.c
${source_dir}/pngset.c
${source_dir}/pngtest.c
${source_dir}/pngtrans.c
${source_dir}/pngwio.c
${source_dir}/pngwrite.c
${source_dir}/pngwtran.c
${source_dir}/pngwutil.c
)
find_package( zlib REQUIRED )
# If you want a shared library instead of static, specify the BUILD_SHARED_LIBS
# variable (which is a built-in CMake option).
add_library( ${project_name} ${sources} ${headers} )
target_link_libraries( ${project_name} PUBLIC ZLIB::ZLIB )
target_include_directories( ${project_name} PUBLIC
$<BUILD_INTERFACE:${source_dir}>
$<INSTALL_INTERFACE:include>
)
############################################################
## INSTALL
############################################################
include( CMakePackageConfigHelpers )
set( PNG_VERSION 1.6.37 )
set( PNG_EXPORT_DIR share/png-${PNG_VERSION}/cmake )
set( PNG_EXPORT_NAME png-export )
install( TARGETS png EXPORT ${PNG_EXPORT_NAME}
RUNTIME DESTINATION bin
LIBRARY DESTINATION lib
ARCHIVE DESTINATION lib
INCLUDES DESTINATION include
)
install( FILES ${headers} DESTINATION include )
install( EXPORT ${PNG_EXPORT_NAME} DESTINATION ${PNG_EXPORT_DIR} )
configure_file( png-config.cmake.in png-config.cmake @ONLY )
write_basic_package_version_file(
png-config-version.cmake
VERSION ${PNG_VERSION}
COMPATIBILITY AnyNewerVersion
)
install(
FILES
${CMAKE_CURRENT_BINARY_DIR}/png-config.cmake
${CMAKE_CURRENT_BINARY_DIR}/png-config-version.cmake
DESTINATION ${PNG_EXPORT_DIR}
)
================================================
FILE: LICENSE
================================================
This copy of the libpng notices is provided for your convenience. In case of
any discrepancy between this copy and the notices in the file png.h that is
included in the libpng distribution, the latter shall prevail.
COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
If you modify libpng you may insert additional notices immediately following
this sentence.
This code is released under the libpng license.
libpng versions 1.2.6, August 15, 2004, through 1.4.1, February 25, 2010, are
Copyright (c) 2004, 2006-2007 Glenn Randers-Pehrson, and are
distributed according to the same disclaimer and license as libpng-1.2.5
with the following individual added to the list of Contributing Authors
Cosmin Truta
libpng versions 1.0.7, July 1, 2000, through 1.2.5 - October 3, 2002, are
Copyright (c) 2000-2002 Glenn Randers-Pehrson, and are
distributed according to the same disclaimer and license as libpng-1.0.6
with the following individuals added to the list of Contributing Authors
Simon-Pierre Cadieux
Eric S. Raymond
Gilles Vollant
and with the following additions to the disclaimer:
There is no warranty against interference with your enjoyment of the
library or against infringement. There is no warranty that our
efforts or the library will fulfill any of your particular purposes
or needs. This library is provided with all faults, and the entire
risk of satisfactory quality, performance, accuracy, and effort is with
the user.
libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
Copyright (c) 1998, 1999 Glenn Randers-Pehrson, and are
distributed according to the same disclaimer and license as libpng-0.96,
with the following individuals added to the list of Contributing Authors:
Tom Lane
Glenn Randers-Pehrson
Willem van Schaik
libpng versions 0.89, June 1996, through 0.96, May 1997, are
Copyright (c) 1996, 1997 Andreas Dilger
Distributed according to the same disclaimer and license as libpng-0.88,
with the following individuals added to the list of Contributing Authors:
John Bowler
Kevin Bracey
Sam Bushell
Magnus Holmgren
Greg Roelofs
Tom Tanner
libpng versions 0.5, May 1995, through 0.88, January 1996, are
Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
For the purposes of this copyright and license, "Contributing Authors"
is defined as the following set of individuals:
Andreas Dilger
Dave Martindale
Guy Eric Schalnat
Paul Schmidt
Tim Wegner
The PNG Reference Library is supplied "AS IS". The Contributing Authors
and Group 42, Inc. disclaim all warranties, expressed or implied,
including, without limitation, the warranties of merchantability and of
fitness for any purpose. The Contributing Authors and Group 42, Inc.
assume no liability for direct, indirect, incidental, special, exemplary,
or consequential damages, which may result from the use of the PNG
Reference Library, even if advised of the possibility of such damage.
Permission is hereby granted to use, copy, modify, and distribute this
source code, or portions hereof, for any purpose, without fee, subject
to the following restrictions:
1. The origin of this source code must not be misrepresented.
2. Altered versions must be plainly marked as such and must not
be misrepresented as being the original source.
3. This Copyright notice may not be removed or altered from any
source or altered source distribution.
The Contributing Authors and Group 42, Inc. specifically permit, without
fee, and encourage the use of this source code as a component to
supporting the PNG file format in commercial products. If you use this
source code in a product, acknowledgment is not required but would be
appreciated.
A "png_get_copyright" function is available, for convenient use in "about"
boxes and the like:
printf("%s",png_get_copyright(NULL));
Also, the PNG logo (in PNG format, of course) is supplied in the
files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
Libpng is OSI Certified Open Source Software. OSI Certified Open Source is a
certification mark of the Open Source Initiative.
Glenn Randers-Pehrson
glennrp at users.sourceforge.net
February 25, 2010
================================================
FILE: README.rst
================================================
libpng for Android
==================
This is a repackaging of libpng 1.6.37 for Android.
Most changes went in config.h and writing the Makefiles.
The original libpng website is : http://www.libpng.org/pub/png/libpng.html
Assuming 'ndk-build' is in your path, you can use the build.sh script to create a static library.
The 'master' branch of this repository contains upstream version 1.6.37. This
hasn't been tested much on Android.
The 'stable' branch of this repository contains the older 1.4.1 version which works fine on Android.
See the wiki_ for an example Android usage and links to documentation.
You might also be interested in lodepng_
.. _wiki: https://github.com/julienr/libpng-android/wiki
.. _lodepng: https://github.com/lvandeve/lodepng
================================================
FILE: build.sh
================================================
#!/bin/sh
ndk-build NDK_PROJECT_PATH=./ $@
================================================
FILE: jni/Android.mk
================================================
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_CFLAGS :=
LOCAL_MODULE := libpng
LOCAL_SRC_FILES :=\
png.c \
pngerror.c \
pngget.c \
pngmem.c \
pngpread.c \
pngread.c \
pngrio.c \
pngrtran.c \
pngrutil.c \
pngset.c \
pngtest.c \
pngtrans.c \
pngwio.c \
pngwrite.c \
pngwtran.c \
pngwutil.c \
arm/arm_init.c \
arm/filter_neon.S \
arm/filter_neon_intrinsics.c \
arm/palette_neon_intrinsics.c
#LOCAL_SHARED_LIBRARIES := -lz
LOCAL_EXPORT_LDLIBS := -lz
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/.
#include $(BUILD_SHARED_LIBRARY)
include $(BUILD_STATIC_LIBRARY)
================================================
FILE: jni/Application.mk
================================================
APP_OPTIM := release
APP_ABI := armeabi-v7a arm64-v8a x86_64 # or all
APP_MODULES := libpng
================================================
FILE: jni/arm/arm_init.c
================================================
/* arm_init.c - NEON optimised filter functions
*
* Copyright (c) 2018 Cosmin Truta
* Copyright (c) 2014,2016 Glenn Randers-Pehrson
* Written by Mans Rullgard, 2011.
*
* This code is released under the libpng license.
* For conditions of distribution and use, see the disclaimer
* and license in png.h
*/
/* Below, after checking __linux__, various non-C90 POSIX 1003.1 functions are
* called.
*/
#define _POSIX_SOURCE 1
#include "../pngpriv.h"
#ifdef PNG_READ_SUPPORTED
#if PNG_ARM_NEON_OPT > 0
#ifdef PNG_ARM_NEON_CHECK_SUPPORTED /* Do run-time checks */
/* WARNING: it is strongly recommended that you do not build libpng with
* run-time checks for CPU features if at all possible. In the case of the ARM
* NEON instructions there is no processor-specific way of detecting the
* presence of the required support, therefore run-time detection is extremely
* OS specific.
*
* You may set the macro PNG_ARM_NEON_FILE to the file name of file containing
* a fragment of C source code which defines the png_have_neon function. There
* are a number of implementations in contrib/arm-neon, but the only one that
* has partial support is contrib/arm-neon/linux.c - a generic Linux
* implementation which reads /proc/cpufino.
*/
#ifndef PNG_ARM_NEON_FILE
# ifdef __linux__
# define PNG_ARM_NEON_FILE "contrib/arm-neon/linux.c"
# endif
#endif
#ifdef PNG_ARM_NEON_FILE
#include <signal.h> /* for sig_atomic_t */
static int png_have_neon(png_structp png_ptr);
#include PNG_ARM_NEON_FILE
#else /* PNG_ARM_NEON_FILE */
# error "PNG_ARM_NEON_FILE undefined: no support for run-time ARM NEON checks"
#endif /* PNG_ARM_NEON_FILE */
#endif /* PNG_ARM_NEON_CHECK_SUPPORTED */
#ifndef PNG_ALIGNED_MEMORY_SUPPORTED
# error "ALIGNED_MEMORY is required; set: -DPNG_ALIGNED_MEMORY_SUPPORTED"
#endif
void
png_init_filter_functions_neon(png_structp pp, unsigned int bpp)
{
/* The switch statement is compiled in for ARM_NEON_API, the call to
* png_have_neon is compiled in for ARM_NEON_CHECK. If both are defined
* the check is only performed if the API has not set the NEON option on
* or off explicitly. In this case the check controls what happens.
*
* If the CHECK is not compiled in and the option is UNSET the behavior prior
* to 1.6.7 was to use the NEON code - this was a bug caused by having the
* wrong order of the 'ON' and 'default' cases. UNSET now defaults to OFF,
* as documented in png.h
*/
png_debug(1, "in png_init_filter_functions_neon");
#ifdef PNG_ARM_NEON_API_SUPPORTED
switch ((pp->options >> PNG_ARM_NEON) & 3)
{
case PNG_OPTION_UNSET:
/* Allow the run-time check to execute if it has been enabled -
* thus both API and CHECK can be turned on. If it isn't supported
* this case will fall through to the 'default' below, which just
* returns.
*/
#endif /* PNG_ARM_NEON_API_SUPPORTED */
#ifdef PNG_ARM_NEON_CHECK_SUPPORTED
{
static volatile sig_atomic_t no_neon = -1; /* not checked */
if (no_neon < 0)
no_neon = !png_have_neon(pp);
if (no_neon)
return;
}
#ifdef PNG_ARM_NEON_API_SUPPORTED
break;
#endif
#endif /* PNG_ARM_NEON_CHECK_SUPPORTED */
#ifdef PNG_ARM_NEON_API_SUPPORTED
default: /* OFF or INVALID */
return;
case PNG_OPTION_ON:
/* Option turned on */
break;
}
#endif
/* IMPORTANT: any new external functions used here must be declared using
* PNG_INTERNAL_FUNCTION in ../pngpriv.h. This is required so that the
* 'prefix' option to configure works:
*
* ./configure --with-libpng-prefix=foobar_
*
* Verify you have got this right by running the above command, doing a build
* and examining pngprefix.h; it must contain a #define for every external
* function you add. (Notice that this happens automatically for the
* initialization function.)
*/
pp->read_filter[PNG_FILTER_VALUE_UP-1] = png_read_filter_row_up_neon;
if (bpp == 3)
{
pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub3_neon;
pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg3_neon;
pp->read_filter[PNG_FILTER_VALUE_PAETH-1] =
png_read_filter_row_paeth3_neon;
}
else if (bpp == 4)
{
pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub4_neon;
pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg4_neon;
pp->read_filter[PNG_FILTER_VALUE_PAETH-1] =
png_read_filter_row_paeth4_neon;
}
}
#endif /* PNG_ARM_NEON_OPT > 0 */
#endif /* READ */
================================================
FILE: jni/arm/filter_neon.S
================================================
/* filter_neon.S - NEON optimised filter functions
*
* Copyright (c) 2018 Cosmin Truta
* Copyright (c) 2014,2017 Glenn Randers-Pehrson
* Written by Mans Rullgard, 2011.
*
* This code is released under the libpng license.
* For conditions of distribution and use, see the disclaimer
* and license in png.h
*/
/* This is required to get the symbol renames, which are #defines, and the
* definitions (or not) of PNG_ARM_NEON_OPT and PNG_ARM_NEON_IMPLEMENTATION.
*/
#define PNG_VERSION_INFO_ONLY
#include "../pngpriv.h"
#if (defined(__linux__) || defined(__FreeBSD__)) && defined(__ELF__)
.section .note.GNU-stack,"",%progbits /* mark stack as non-executable */
#endif
#ifdef PNG_READ_SUPPORTED
/* Assembler NEON support - only works for 32-bit ARM (i.e. it does not work for
* ARM64). The code in arm/filter_neon_intrinsics.c supports ARM64, however it
* only works if -mfpu=neon is specified on the GCC command line. See pngpriv.h
* for the logic which sets PNG_USE_ARM_NEON_ASM:
*/
#if PNG_ARM_NEON_IMPLEMENTATION == 2 /* hand-coded assembler */
#if PNG_ARM_NEON_OPT > 0
#ifdef __ELF__
# define ELF
#else
# define ELF @
#endif
.arch armv7-a
.fpu neon
.macro func name, export=0
.macro endfunc
ELF .size \name, . - \name
.endfunc
.purgem endfunc
.endm
.text
/* Explicitly specifying alignment here because some versions of
* GAS don't align code correctly. This is harmless in correctly
* written versions of GAS.
*/
.align 2
.if \export
.global \name
.endif
ELF .type \name, STT_FUNC
.func \name
\name:
.endm
func png_read_filter_row_sub4_neon, export=1
ldr r3, [r0, #4] @ rowbytes
vmov.i8 d3, #0
1:
vld4.32 {d4[],d5[],d6[],d7[]}, [r1,:128]
vadd.u8 d0, d3, d4
vadd.u8 d1, d0, d5
vadd.u8 d2, d1, d6
vadd.u8 d3, d2, d7
vst4.32 {d0[0],d1[0],d2[0],d3[0]},[r1,:128]!
subs r3, r3, #16
bgt 1b
bx lr
endfunc
func png_read_filter_row_sub3_neon, export=1
ldr r3, [r0, #4] @ rowbytes
vmov.i8 d3, #0
mov r0, r1
mov r2, #3
mov r12, #12
vld1.8 {q11}, [r0], r12
1:
vext.8 d5, d22, d23, #3
vadd.u8 d0, d3, d22
vext.8 d6, d22, d23, #6
vadd.u8 d1, d0, d5
vext.8 d7, d23, d23, #1
vld1.8 {q11}, [r0], r12
vst1.32 {d0[0]}, [r1,:32], r2
vadd.u8 d2, d1, d6
vst1.32 {d1[0]}, [r1], r2
vadd.u8 d3, d2, d7
vst1.32 {d2[0]}, [r1], r2
vst1.32 {d3[0]}, [r1], r2
subs r3, r3, #12
bgt 1b
bx lr
endfunc
func png_read_filter_row_up_neon, export=1
ldr r3, [r0, #4] @ rowbytes
1:
vld1.8 {q0}, [r1,:128]
vld1.8 {q1}, [r2,:128]!
vadd.u8 q0, q0, q1
vst1.8 {q0}, [r1,:128]!
subs r3, r3, #16
bgt 1b
bx lr
endfunc
func png_read_filter_row_avg4_neon, export=1
ldr r12, [r0, #4] @ rowbytes
vmov.i8 d3, #0
1:
vld4.32 {d4[],d5[],d6[],d7[]}, [r1,:128]
vld4.32 {d16[],d17[],d18[],d19[]},[r2,:128]!
vhadd.u8 d0, d3, d16
vadd.u8 d0, d0, d4
vhadd.u8 d1, d0, d17
vadd.u8 d1, d1, d5
vhadd.u8 d2, d1, d18
vadd.u8 d2, d2, d6
vhadd.u8 d3, d2, d19
vadd.u8 d3, d3, d7
vst4.32 {d0[0],d1[0],d2[0],d3[0]},[r1,:128]!
subs r12, r12, #16
bgt 1b
bx lr
endfunc
func png_read_filter_row_avg3_neon, export=1
push {r4,lr}
ldr r12, [r0, #4] @ rowbytes
vmov.i8 d3, #0
mov r0, r1
mov r4, #3
mov lr, #12
vld1.8 {q11}, [r0], lr
1:
vld1.8 {q10}, [r2], lr
vext.8 d5, d22, d23, #3
vhadd.u8 d0, d3, d20
vext.8 d17, d20, d21, #3
vadd.u8 d0, d0, d22
vext.8 d6, d22, d23, #6
vhadd.u8 d1, d0, d17
vext.8 d18, d20, d21, #6
vadd.u8 d1, d1, d5
vext.8 d7, d23, d23, #1
vld1.8 {q11}, [r0], lr
vst1.32 {d0[0]}, [r1,:32], r4
vhadd.u8 d2, d1, d18
vst1.32 {d1[0]}, [r1], r4
vext.8 d19, d21, d21, #1
vadd.u8 d2, d2, d6
vhadd.u8 d3, d2, d19
vst1.32 {d2[0]}, [r1], r4
vadd.u8 d3, d3, d7
vst1.32 {d3[0]}, [r1], r4
subs r12, r12, #12
bgt 1b
pop {r4,pc}
endfunc
.macro paeth rx, ra, rb, rc
vaddl.u8 q12, \ra, \rb @ a + b
vaddl.u8 q15, \rc, \rc @ 2*c
vabdl.u8 q13, \rb, \rc @ pa
vabdl.u8 q14, \ra, \rc @ pb
vabd.u16 q15, q12, q15 @ pc
vcle.u16 q12, q13, q14 @ pa <= pb
vcle.u16 q13, q13, q15 @ pa <= pc
vcle.u16 q14, q14, q15 @ pb <= pc
vand q12, q12, q13 @ pa <= pb && pa <= pc
vmovn.u16 d28, q14
vmovn.u16 \rx, q12
vbsl d28, \rb, \rc
vbsl \rx, \ra, d28
.endm
func png_read_filter_row_paeth4_neon, export=1
ldr r12, [r0, #4] @ rowbytes
vmov.i8 d3, #0
vmov.i8 d20, #0
1:
vld4.32 {d4[],d5[],d6[],d7[]}, [r1,:128]
vld4.32 {d16[],d17[],d18[],d19[]},[r2,:128]!
paeth d0, d3, d16, d20
vadd.u8 d0, d0, d4
paeth d1, d0, d17, d16
vadd.u8 d1, d1, d5
paeth d2, d1, d18, d17
vadd.u8 d2, d2, d6
paeth d3, d2, d19, d18
vmov d20, d19
vadd.u8 d3, d3, d7
vst4.32 {d0[0],d1[0],d2[0],d3[0]},[r1,:128]!
subs r12, r12, #16
bgt 1b
bx lr
endfunc
func png_read_filter_row_paeth3_neon, export=1
push {r4,lr}
ldr r12, [r0, #4] @ rowbytes
vmov.i8 d3, #0
vmov.i8 d4, #0
mov r0, r1
mov r4, #3
mov lr, #12
vld1.8 {q11}, [r0], lr
1:
vld1.8 {q10}, [r2], lr
paeth d0, d3, d20, d4
vext.8 d5, d22, d23, #3
vadd.u8 d0, d0, d22
vext.8 d17, d20, d21, #3
paeth d1, d0, d17, d20
vst1.32 {d0[0]}, [r1,:32], r4
vext.8 d6, d22, d23, #6
vadd.u8 d1, d1, d5
vext.8 d18, d20, d21, #6
paeth d2, d1, d18, d17
vext.8 d7, d23, d23, #1
vld1.8 {q11}, [r0], lr
vst1.32 {d1[0]}, [r1], r4
vadd.u8 d2, d2, d6
vext.8 d19, d21, d21, #1
paeth d3, d2, d19, d18
vst1.32 {d2[0]}, [r1], r4
vmov d4, d19
vadd.u8 d3, d3, d7
vst1.32 {d3[0]}, [r1], r4
subs r12, r12, #12
bgt 1b
pop {r4,pc}
endfunc
#endif /* PNG_ARM_NEON_OPT > 0 */
#endif /* PNG_ARM_NEON_IMPLEMENTATION == 2 (assembler) */
#endif /* READ */
================================================
FILE: jni/arm/filter_neon_intrinsics.c
================================================
/* filter_neon_intrinsics.c - NEON optimised filter functions
*
* Copyright (c) 2018 Cosmin Truta
* Copyright (c) 2014,2016 Glenn Randers-Pehrson
* Written by James Yu <james.yu at linaro.org>, October 2013.
* Based on filter_neon.S, written by Mans Rullgard, 2011.
*
* This code is released under the libpng license.
* For conditions of distribution and use, see the disclaimer
* and license in png.h
*/
#include "../pngpriv.h"
#ifdef PNG_READ_SUPPORTED
/* This code requires -mfpu=neon on the command line: */
#if PNG_ARM_NEON_IMPLEMENTATION == 1 /* intrinsics code from pngpriv.h */
#if defined(_MSC_VER) && defined(_M_ARM64)
# include <arm64_neon.h>
#else
# include <arm_neon.h>
#endif
/* libpng row pointers are not necessarily aligned to any particular boundary,
* however this code will only work with appropriate alignment. arm/arm_init.c
* checks for this (and will not compile unless it is done). This code uses
* variants of png_aligncast to avoid compiler warnings.
*/
#define png_ptr(type,pointer) png_aligncast(type *,pointer)
#define png_ptrc(type,pointer) png_aligncastconst(const type *,pointer)
/* The following relies on a variable 'temp_pointer' being declared with type
* 'type'. This is written this way just to hide the GCC strict aliasing
* warning; note that the code is safe because there never is an alias between
* the input and output pointers.
*
* When compiling with MSVC ARM64, the png_ldr macro can't be passed directly
* to vst4_lane_u32, because of an internal compiler error inside MSVC.
* To avoid this compiler bug, we use a temporary variable (vdest_val) to store
* the result of png_ldr.
*/
#define png_ldr(type,pointer)\
(temp_pointer = png_ptr(type,pointer), *temp_pointer)
#if PNG_ARM_NEON_OPT > 0
void
png_read_filter_row_up_neon(png_row_infop row_info, png_bytep row,
png_const_bytep prev_row)
{
png_bytep rp = row;
png_bytep rp_stop = row + row_info->rowbytes;
png_const_bytep pp = prev_row;
png_debug(1, "in png_read_filter_row_up_neon");
for (; rp < rp_stop; rp += 16, pp += 16)
{
uint8x16_t qrp, qpp;
qrp = vld1q_u8(rp);
qpp = vld1q_u8(pp);
qrp = vaddq_u8(qrp, qpp);
vst1q_u8(rp, qrp);
}
}
void
png_read_filter_row_sub3_neon(png_row_infop row_info, png_bytep row,
png_const_bytep prev_row)
{
png_bytep rp = row;
png_bytep rp_stop = row + row_info->rowbytes;
uint8x16_t vtmp = vld1q_u8(rp);
uint8x8x2_t *vrpt = png_ptr(uint8x8x2_t, &vtmp);
uint8x8x2_t vrp = *vrpt;
uint8x8x4_t vdest;
vdest.val[3] = vdup_n_u8(0);
png_debug(1, "in png_read_filter_row_sub3_neon");
for (; rp < rp_stop;)
{
uint8x8_t vtmp1, vtmp2;
uint32x2_t *temp_pointer;
vtmp1 = vext_u8(vrp.val[0], vrp.val[1], 3);
vdest.val[0] = vadd_u8(vdest.val[3], vrp.val[0]);
vtmp2 = vext_u8(vrp.val[0], vrp.val[1], 6);
vdest.val[1] = vadd_u8(vdest.val[0], vtmp1);
vtmp1 = vext_u8(vrp.val[1], vrp.val[1], 1);
vdest.val[2] = vadd_u8(vdest.val[1], vtmp2);
vdest.val[3] = vadd_u8(vdest.val[2], vtmp1);
vtmp = vld1q_u8(rp + 12);
vrpt = png_ptr(uint8x8x2_t, &vtmp);
vrp = *vrpt;
vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[0]), 0);
rp += 3;
vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[1]), 0);
rp += 3;
vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[2]), 0);
rp += 3;
vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[3]), 0);
rp += 3;
}
PNG_UNUSED(prev_row)
}
void
png_read_filter_row_sub4_neon(png_row_infop row_info, png_bytep row,
png_const_bytep prev_row)
{
png_bytep rp = row;
png_bytep rp_stop = row + row_info->rowbytes;
uint8x8x4_t vdest;
vdest.val[3] = vdup_n_u8(0);
png_debug(1, "in png_read_filter_row_sub4_neon");
for (; rp < rp_stop; rp += 16)
{
uint32x2x4_t vtmp = vld4_u32(png_ptr(uint32_t,rp));
uint8x8x4_t *vrpt = png_ptr(uint8x8x4_t,&vtmp);
uint8x8x4_t vrp = *vrpt;
uint32x2x4_t *temp_pointer;
uint32x2x4_t vdest_val;
vdest.val[0] = vadd_u8(vdest.val[3], vrp.val[0]);
vdest.val[1] = vadd_u8(vdest.val[0], vrp.val[1]);
vdest.val[2] = vadd_u8(vdest.val[1], vrp.val[2]);
vdest.val[3] = vadd_u8(vdest.val[2], vrp.val[3]);
vdest_val = png_ldr(uint32x2x4_t, &vdest);
vst4_lane_u32(png_ptr(uint32_t,rp), vdest_val, 0);
}
PNG_UNUSED(prev_row)
}
void
png_read_filter_row_avg3_neon(png_row_infop row_info, png_bytep row,
png_const_bytep prev_row)
{
png_bytep rp = row;
png_const_bytep pp = prev_row;
png_bytep rp_stop = row + row_info->rowbytes;
uint8x16_t vtmp;
uint8x8x2_t *vrpt;
uint8x8x2_t vrp;
uint8x8x4_t vdest;
vdest.val[3] = vdup_n_u8(0);
vtmp = vld1q_u8(rp);
vrpt = png_ptr(uint8x8x2_t,&vtmp);
vrp = *vrpt;
png_debug(1, "in png_read_filter_row_avg3_neon");
for (; rp < rp_stop; pp += 12)
{
uint8x8_t vtmp1, vtmp2, vtmp3;
uint8x8x2_t *vppt;
uint8x8x2_t vpp;
uint32x2_t *temp_pointer;
vtmp = vld1q_u8(pp);
vppt = png_ptr(uint8x8x2_t,&vtmp);
vpp = *vppt;
vtmp1 = vext_u8(vrp.val[0], vrp.val[1], 3);
vdest.val[0] = vhadd_u8(vdest.val[3], vpp.val[0]);
vdest.val[0] = vadd_u8(vdest.val[0], vrp.val[0]);
vtmp2 = vext_u8(vpp.val[0], vpp.val[1], 3);
vtmp3 = vext_u8(vrp.val[0], vrp.val[1], 6);
vdest.val[1] = vhadd_u8(vdest.val[0], vtmp2);
vdest.val[1] = vadd_u8(vdest.val[1], vtmp1);
vtmp2 = vext_u8(vpp.val[0], vpp.val[1], 6);
vtmp1 = vext_u8(vrp.val[1], vrp.val[1], 1);
vtmp = vld1q_u8(rp + 12);
vrpt = png_ptr(uint8x8x2_t,&vtmp);
vrp = *vrpt;
vdest.val[2] = vhadd_u8(vdest.val[1], vtmp2);
vdest.val[2] = vadd_u8(vdest.val[2], vtmp3);
vtmp2 = vext_u8(vpp.val[1], vpp.val[1], 1);
vdest.val[3] = vhadd_u8(vdest.val[2], vtmp2);
vdest.val[3] = vadd_u8(vdest.val[3], vtmp1);
vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[0]), 0);
rp += 3;
vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[1]), 0);
rp += 3;
vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[2]), 0);
rp += 3;
vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[3]), 0);
rp += 3;
}
}
void
png_read_filter_row_avg4_neon(png_row_infop row_info, png_bytep row,
png_const_bytep prev_row)
{
png_bytep rp = row;
png_bytep rp_stop = row + row_info->rowbytes;
png_const_bytep pp = prev_row;
uint8x8x4_t vdest;
vdest.val[3] = vdup_n_u8(0);
png_debug(1, "in png_read_filter_row_avg4_neon");
for (; rp < rp_stop; rp += 16, pp += 16)
{
uint32x2x4_t vtmp;
uint8x8x4_t *vrpt, *vppt;
uint8x8x4_t vrp, vpp;
uint32x2x4_t *temp_pointer;
uint32x2x4_t vdest_val;
vtmp = vld4_u32(png_ptr(uint32_t,rp));
vrpt = png_ptr(uint8x8x4_t,&vtmp);
vrp = *vrpt;
vtmp = vld4_u32(png_ptrc(uint32_t,pp));
vppt = png_ptr(uint8x8x4_t,&vtmp);
vpp = *vppt;
vdest.val[0] = vhadd_u8(vdest.val[3], vpp.val[0]);
vdest.val[0] = vadd_u8(vdest.val[0], vrp.val[0]);
vdest.val[1] = vhadd_u8(vdest.val[0], vpp.val[1]);
vdest.val[1] = vadd_u8(vdest.val[1], vrp.val[1]);
vdest.val[2] = vhadd_u8(vdest.val[1], vpp.val[2]);
vdest.val[2] = vadd_u8(vdest.val[2], vrp.val[2]);
vdest.val[3] = vhadd_u8(vdest.val[2], vpp.val[3]);
vdest.val[3] = vadd_u8(vdest.val[3], vrp.val[3]);
vdest_val = png_ldr(uint32x2x4_t, &vdest);
vst4_lane_u32(png_ptr(uint32_t,rp), vdest_val, 0);
}
}
static uint8x8_t
paeth(uint8x8_t a, uint8x8_t b, uint8x8_t c)
{
uint8x8_t d, e;
uint16x8_t p1, pa, pb, pc;
p1 = vaddl_u8(a, b); /* a + b */
pc = vaddl_u8(c, c); /* c * 2 */
pa = vabdl_u8(b, c); /* pa */
pb = vabdl_u8(a, c); /* pb */
pc = vabdq_u16(p1, pc); /* pc */
p1 = vcleq_u16(pa, pb); /* pa <= pb */
pa = vcleq_u16(pa, pc); /* pa <= pc */
pb = vcleq_u16(pb, pc); /* pb <= pc */
p1 = vandq_u16(p1, pa); /* pa <= pb && pa <= pc */
d = vmovn_u16(pb);
e = vmovn_u16(p1);
d = vbsl_u8(d, b, c);
e = vbsl_u8(e, a, d);
return e;
}
void
png_read_filter_row_paeth3_neon(png_row_infop row_info, png_bytep row,
png_const_bytep prev_row)
{
png_bytep rp = row;
png_const_bytep pp = prev_row;
png_bytep rp_stop = row + row_info->rowbytes;
uint8x16_t vtmp;
uint8x8x2_t *vrpt;
uint8x8x2_t vrp;
uint8x8_t vlast = vdup_n_u8(0);
uint8x8x4_t vdest;
vdest.val[3] = vdup_n_u8(0);
vtmp = vld1q_u8(rp);
vrpt = png_ptr(uint8x8x2_t,&vtmp);
vrp = *vrpt;
png_debug(1, "in png_read_filter_row_paeth3_neon");
for (; rp < rp_stop; pp += 12)
{
uint8x8x2_t *vppt;
uint8x8x2_t vpp;
uint8x8_t vtmp1, vtmp2, vtmp3;
uint32x2_t *temp_pointer;
vtmp = vld1q_u8(pp);
vppt = png_ptr(uint8x8x2_t,&vtmp);
vpp = *vppt;
vdest.val[0] = paeth(vdest.val[3], vpp.val[0], vlast);
vdest.val[0] = vadd_u8(vdest.val[0], vrp.val[0]);
vtmp1 = vext_u8(vrp.val[0], vrp.val[1], 3);
vtmp2 = vext_u8(vpp.val[0], vpp.val[1], 3);
vdest.val[1] = paeth(vdest.val[0], vtmp2, vpp.val[0]);
vdest.val[1] = vadd_u8(vdest.val[1], vtmp1);
vtmp1 = vext_u8(vrp.val[0], vrp.val[1], 6);
vtmp3 = vext_u8(vpp.val[0], vpp.val[1], 6);
vdest.val[2] = paeth(vdest.val[1], vtmp3, vtmp2);
vdest.val[2] = vadd_u8(vdest.val[2], vtmp1);
vtmp1 = vext_u8(vrp.val[1], vrp.val[1], 1);
vtmp2 = vext_u8(vpp.val[1], vpp.val[1], 1);
vtmp = vld1q_u8(rp + 12);
vrpt = png_ptr(uint8x8x2_t,&vtmp);
vrp = *vrpt;
vdest.val[3] = paeth(vdest.val[2], vtmp2, vtmp3);
vdest.val[3] = vadd_u8(vdest.val[3], vtmp1);
vlast = vtmp2;
vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[0]), 0);
rp += 3;
vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[1]), 0);
rp += 3;
vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[2]), 0);
rp += 3;
vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[3]), 0);
rp += 3;
}
}
void
png_read_filter_row_paeth4_neon(png_row_infop row_info, png_bytep row,
png_const_bytep prev_row)
{
png_bytep rp = row;
png_bytep rp_stop = row + row_info->rowbytes;
png_const_bytep pp = prev_row;
uint8x8_t vlast = vdup_n_u8(0);
uint8x8x4_t vdest;
vdest.val[3] = vdup_n_u8(0);
png_debug(1, "in png_read_filter_row_paeth4_neon");
for (; rp < rp_stop; rp += 16, pp += 16)
{
uint32x2x4_t vtmp;
uint8x8x4_t *vrpt, *vppt;
uint8x8x4_t vrp, vpp;
uint32x2x4_t *temp_pointer;
uint32x2x4_t vdest_val;
vtmp = vld4_u32(png_ptr(uint32_t,rp));
vrpt = png_ptr(uint8x8x4_t,&vtmp);
vrp = *vrpt;
vtmp = vld4_u32(png_ptrc(uint32_t,pp));
vppt = png_ptr(uint8x8x4_t,&vtmp);
vpp = *vppt;
vdest.val[0] = paeth(vdest.val[3], vpp.val[0], vlast);
vdest.val[0] = vadd_u8(vdest.val[0], vrp.val[0]);
vdest.val[1] = paeth(vdest.val[0], vpp.val[1], vpp.val[0]);
vdest.val[1] = vadd_u8(vdest.val[1], vrp.val[1]);
vdest.val[2] = paeth(vdest.val[1], vpp.val[2], vpp.val[1]);
vdest.val[2] = vadd_u8(vdest.val[2], vrp.val[2]);
vdest.val[3] = paeth(vdest.val[2], vpp.val[3], vpp.val[2]);
vdest.val[3] = vadd_u8(vdest.val[3], vrp.val[3]);
vlast = vpp.val[3];
vdest_val = png_ldr(uint32x2x4_t, &vdest);
vst4_lane_u32(png_ptr(uint32_t,rp), vdest_val, 0);
}
}
#endif /* PNG_ARM_NEON_OPT > 0 */
#endif /* PNG_ARM_NEON_IMPLEMENTATION == 1 (intrinsics) */
#endif /* READ */
================================================
FILE: jni/arm/palette_neon_intrinsics.c
================================================
/* palette_neon_intrinsics.c - NEON optimised palette expansion functions
*
* Copyright (c) 2018-2019 Cosmin Truta
* Copyright (c) 2017-2018 Arm Holdings. All rights reserved.
* Written by Richard Townsend <Richard.Townsend@arm.com>, February 2017.
*
* This code is released under the libpng license.
* For conditions of distribution and use, see the disclaimer
* and license in png.h
*/
#include "../pngpriv.h"
#if PNG_ARM_NEON_IMPLEMENTATION == 1
#if defined(_MSC_VER) && defined(_M_ARM64)
# include <arm64_neon.h>
#else
# include <arm_neon.h>
#endif
/* Build an RGBA8 palette from the separate RGB and alpha palettes. */
void
png_riffle_palette_neon(png_structrp png_ptr)
{
png_const_colorp palette = png_ptr->palette;
png_bytep riffled_palette = png_ptr->riffled_palette;
png_const_bytep trans_alpha = png_ptr->trans_alpha;
int num_trans = png_ptr->num_trans;
int i;
png_debug(1, "in png_riffle_palette_neon");
/* Initially black, opaque. */
uint8x16x4_t w = {{
vdupq_n_u8(0x00),
vdupq_n_u8(0x00),
vdupq_n_u8(0x00),
vdupq_n_u8(0xff),
}};
/* First, riffle the RGB colours into an RGBA8 palette.
* The alpha component is set to opaque for now.
*/
for (i = 0; i < 256; i += 16)
{
uint8x16x3_t v = vld3q_u8((png_const_bytep)(palette + i));
w.val[0] = v.val[0];
w.val[1] = v.val[1];
w.val[2] = v.val[2];
vst4q_u8(riffled_palette + (i << 2), w);
}
/* Fix up the missing transparency values. */
for (i = 0; i < num_trans; i++)
riffled_palette[(i << 2) + 3] = trans_alpha[i];
}
/* Expands a palettized row into RGBA8. */
int
png_do_expand_palette_rgba8_neon(png_structrp png_ptr, png_row_infop row_info,
png_const_bytep row, png_bytepp ssp, png_bytepp ddp)
{
png_uint_32 row_width = row_info->width;
const png_uint_32 *riffled_palette =
(const png_uint_32 *)png_ptr->riffled_palette;
const png_int_32 pixels_per_chunk = 4;
int i;
png_debug(1, "in png_do_expand_palette_rgba8_neon");
if (row_width < pixels_per_chunk)
return 0;
/* This function originally gets the last byte of the output row.
* The NEON part writes forward from a given position, so we have
* to seek this back by 4 pixels x 4 bytes.
*/
*ddp = *ddp - ((pixels_per_chunk * sizeof(png_uint_32)) - 1);
for (i = 0; i < row_width; i += pixels_per_chunk)
{
uint32x4_t cur;
png_bytep sp = *ssp - i, dp = *ddp - (i << 2);
cur = vld1q_dup_u32 (riffled_palette + *(sp - 3));
cur = vld1q_lane_u32(riffled_palette + *(sp - 2), cur, 1);
cur = vld1q_lane_u32(riffled_palette + *(sp - 1), cur, 2);
cur = vld1q_lane_u32(riffled_palette + *(sp - 0), cur, 3);
vst1q_u32((void *)dp, cur);
}
if (i != row_width)
{
/* Remove the amount that wasn't processed. */
i -= pixels_per_chunk;
}
/* Decrement output pointers. */
*ssp = *ssp - i;
*ddp = *ddp - (i << 2);
return i;
}
/* Expands a palettized row into RGB8. */
int
png_do_expand_palette_rgb8_neon(png_structrp png_ptr, png_row_infop row_info,
png_const_bytep row, png_bytepp ssp, png_bytepp ddp)
{
png_uint_32 row_width = row_info->width;
png_const_bytep palette = (png_const_bytep)png_ptr->palette;
const png_uint_32 pixels_per_chunk = 8;
int i;
png_debug(1, "in png_do_expand_palette_rgb8_neon");
if (row_width <= pixels_per_chunk)
return 0;
/* Seeking this back by 8 pixels x 3 bytes. */
*ddp = *ddp - ((pixels_per_chunk * sizeof(png_color)) - 1);
for (i = 0; i < row_width; i += pixels_per_chunk)
{
uint8x8x3_t cur;
png_bytep sp = *ssp - i, dp = *ddp - ((i << 1) + i);
cur = vld3_dup_u8(palette + sizeof(png_color) * (*(sp - 7)));
cur = vld3_lane_u8(palette + sizeof(png_color) * (*(sp - 6)), cur, 1);
cur = vld3_lane_u8(palette + sizeof(png_color) * (*(sp - 5)), cur, 2);
cur = vld3_lane_u8(palette + sizeof(png_color) * (*(sp - 4)), cur, 3);
cur = vld3_lane_u8(palette + sizeof(png_color) * (*(sp - 3)), cur, 4);
cur = vld3_lane_u8(palette + sizeof(png_color) * (*(sp - 2)), cur, 5);
cur = vld3_lane_u8(palette + sizeof(png_color) * (*(sp - 1)), cur, 6);
cur = vld3_lane_u8(palette + sizeof(png_color) * (*(sp - 0)), cur, 7);
vst3_u8((void *)dp, cur);
}
if (i != row_width)
{
/* Remove the amount that wasn't processed. */
i -= pixels_per_chunk;
}
/* Decrement output pointers. */
*ssp = *ssp - i;
*ddp = *ddp - ((i << 1) + i);
return i;
}
#endif /* PNG_ARM_NEON_IMPLEMENTATION */
================================================
FILE: jni/config.h
================================================
/* config.h. Generated from config.h.in by configure. */
/* config.h.in. Generated from configure.ac by autoheader. */
/* Define to 1 if you have the <dlfcn.h> header file. */
#define HAVE_DLFCN_H 0
/* Define to 1 if you have the <inttypes.h> header file. */
#define HAVE_INTTYPES_H 0
/* Define to 1 if you have the `m' library (-lm). */
#define HAVE_LIBM 1
/* Define to 1 if you have the `z' library (-lz). */
#define HAVE_LIBZ 1
/* Define to 1 if you have the <malloc.h> header file. */
#define HAVE_MALLOC_H 1
/* Define to 1 if you have the <memory.h> header file. */
#define HAVE_MEMORY_H 0
/* Define to 1 if you have the `memset' function. */
#define HAVE_MEMSET 1
/* Define to 1 if you have the `pow' function. */
/* #undef HAVE_POW */
/* Define to 1 if you have the <stdint.h> header file. */
#define HAVE_STDINT_H 1
/* Define to 1 if you have the <stdlib.h> header file. */
#define HAVE_STDLIB_H 1
/* Define to 1 if you have the <strings.h> header file. */
#define HAVE_STRINGS_H 1
/* Define to 1 if you have the <string.h> header file. */
#define HAVE_STRING_H 1
/* Define to 1 if you have the <sys/stat.h> header file. */
#define HAVE_SYS_STAT_H 1
/* Define to 1 if you have the <sys/types.h> header file. */
#define HAVE_SYS_TYPES_H 1
/* Define to 1 if you have the <unistd.h> header file. */
#define HAVE_UNISTD_H 1
/* Define to the sub-directory in which libtool stores uninstalled libraries.
*/
#define LT_OBJDIR ".libs/"
/* Name of package */
#define PACKAGE "libpng"
/* Define to the address where bug reports for this package should be sent. */
#define PACKAGE_BUGREPORT "png-mng-implement@lists.sourceforge.net"
/* Define to the full name of this package. */
#define PACKAGE_NAME "libpng"
/* Define to the full name and version of this package. */
#define PACKAGE_STRING "libpng 1.6.37"
/* Define to the one symbol short name of this package. */
#define PACKAGE_TARNAME "libpng"
/* Define to the home page for this package. */
#define PACKAGE_URL ""
/* Define to the version of this package. */
#define PACKAGE_VERSION "1.6.37"
/* Define to 1 if you have the ANSI C header files. */
#define STDC_HEADERS 1
/* Define to 1 if your <sys/time.h> declares `struct tm'. */
/* #undef TM_IN_SYS_TIME */
/* Version number of package */
#define VERSION "1.6.37"
/* Define to empty if `const' does not conform to ANSI C. */
/* #undef const */
/* Define to `unsigned int' if <sys/types.h> does not define. */
/* #undef size_t */
================================================
FILE: jni/example.c
================================================
#if 0 /* in case someone actually tries to compile this */
/* example.c - an example of using libpng
*
* Maintained 2018 Cosmin Truta
* Maintained 1998-2016 Glenn Randers-Pehrson
* Maintained 1996-1997 Andreas Dilger
* Written 1995-1996 Guy Eric Schalnat, Group 42, Inc.
*
* To the extent possible under law, the authors have waived
* all copyright and related or neighboring rights to this file.
* This work is published from: United States, Canada.
*/
/* This is an example of how to use libpng to read and write PNG files.
* The file libpng-manual.txt is much more verbose then this. If you have
* not read it, do so first. This was designed to be a starting point of an
* implementation. This is not officially part of libpng, is hereby placed
* in the public domain, and therefore does not require a copyright notice.
*
* This file does not currently compile, because it is missing certain
* parts, like allocating memory to hold an image. You will have to
* supply these parts to get it to compile. For an example of a minimal
* working PNG reader/writer, see pngtest.c, included in this distribution;
* see also the programs in the contrib directory.
*/
/* The simple, but restricted approach to reading a PNG file or data stream
* requires just two function calls, as in the following complete program.
* Writing a file needs just one function call, so long as the data has an
* appropriate layout.
*
* The following code reads PNG image data from a file and writes it, in a
* potentially new format, to a new file. While this code will compile, there
* is minimal (insufficient) error checking. For a more realistic version,
* see contrib/examples/pngtopng.c
*/
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <png.h>
#include <zlib.h>
int main(int argc, const char **argv)
{
if (argc == 3)
{
png_image image; /* The control structure used by libpng */
/* Initialize the 'png_image' structure. */
memset(&image, 0, (sizeof image));
image.version = PNG_IMAGE_VERSION;
/* The first argument is the file to read: */
if (png_image_begin_read_from_file(&image, argv[1]) != 0)
{
png_bytep buffer;
/* Set the format in which to read the PNG file; this code chooses a
* simple sRGB format with a non-associated alpha channel, adequate to
* store most images.
*/
image.format = PNG_FORMAT_RGBA;
/* Now allocate enough memory to hold the image in this format; the
* PNG_IMAGE_SIZE macro uses the information about the image (width,
* height and format) stored in 'image'.
*/
buffer = malloc(PNG_IMAGE_SIZE(image));
/* If enough memory was available, read the image in the desired
* format, then write the result out to the new file. 'background' is
* not necessary when reading the image, because the alpha channel is
* preserved; if it were to be removed, for example if we requested
* PNG_FORMAT_RGB, then either a solid background color would have to
* be supplied, or the output buffer would have to be initialized to
* the actual background of the image.
*
* The fourth argument to png_image_finish_read is the 'row_stride' -
* this is the number of components allocated for the image in each
* row. It has to be at least as big as the value returned by
* PNG_IMAGE_ROW_STRIDE, but if you just allocate space for the
* default, minimum size, using PNG_IMAGE_SIZE as above, you can pass
* zero.
*
* The final argument is a pointer to a buffer for the colormap;
* colormaps have exactly the same format as a row of image pixels
* (so you choose what format to make the colormap by setting
* image.format). A colormap is only returned if
* PNG_FORMAT_FLAG_COLORMAP is also set in image.format, so in this
* case NULL is passed as the final argument. If you do want to force
* all images into an index/color-mapped format, then you can use:
*
* PNG_IMAGE_COLORMAP_SIZE(image)
*
* to find the maximum size of the colormap in bytes.
*/
if (buffer != NULL &&
png_image_finish_read(&image, NULL/*background*/, buffer,
0/*row_stride*/, NULL/*colormap*/) != 0)
{
/* Now write the image out to the second argument. In the write
* call 'convert_to_8bit' allows 16-bit data to be squashed down to
* 8 bits; this isn't necessary here because the original read was
* to the 8-bit format.
*/
if (png_image_write_to_file(&image, argv[2], 0/*convert_to_8bit*/,
buffer, 0/*row_stride*/, NULL/*colormap*/) != 0)
{
/* The image has been written successfully. */
exit(0);
}
}
else
{
/* Calling png_image_free is optional unless the simplified API was
* not run to completion. In this case, if there wasn't enough
* memory for 'buffer', we didn't complete the read, so we must
* free the image:
*/
if (buffer == NULL)
png_image_free(&image);
else
free(buffer);
}
/* Something went wrong reading or writing the image. libpng stores a
* textual message in the 'png_image' structure:
*/
fprintf(stderr, "pngtopng: error: %s\n", image.message);
exit(1);
}
fprintf(stderr, "pngtopng: usage: pngtopng input-file output-file\n");
exit(2);
}
/* That's it ;-) Of course you probably want to do more with PNG files than
* just converting them all to 32-bit RGBA PNG files; you can do that between
* the call to png_image_finish_read and png_image_write_to_file. You can also
* ask for the image data to be presented in a number of different formats.
* You do this by simply changing the 'format' parameter set before allocating
* the buffer.
*
* The format parameter consists of five flags that define various aspects of
* the image. You can simply add these together to get the format, or you can
* use one of the predefined macros from png.h (as above):
*
* PNG_FORMAT_FLAG_COLOR: if set, the image will have three color components
* per pixel (red, green and blue); if not set, the image will just have one
* luminance (grayscale) component.
*
* PNG_FORMAT_FLAG_ALPHA: if set, each pixel in the image will have an
* additional alpha value; a linear value that describes the degree the
* image pixel covers (overwrites) the contents of the existing pixel on the
* display.
*
* PNG_FORMAT_FLAG_LINEAR: if set, the components of each pixel will be
* returned as a series of 16-bit linear values; if not set, the components
* will be returned as a series of 8-bit values encoded according to the
* sRGB standard. The 8-bit format is the normal format for images intended
* for direct display, because almost all display devices do the inverse of
* the sRGB transformation to the data they receive. The 16-bit format is
* more common for scientific data and image data that must be further
* processed; because it is linear, simple math can be done on the component
* values. Regardless of the setting of this flag, the alpha channel is
* always linear, although it will be 8 bits or 16 bits wide as specified by
* the flag.
*
* PNG_FORMAT_FLAG_BGR: if set, the components of a color pixel will be
* returned in the order blue, then green, then red. If not set, the pixel
* components are in the order red, then green, then blue.
*
* PNG_FORMAT_FLAG_AFIRST: if set, the alpha channel (if present) precedes the
* color or grayscale components. If not set, the alpha channel follows the
* components.
*
* You do not have to read directly from a file. You can read from memory or,
* on systems that support it, from a <stdio.h> FILE*. This is controlled by
* the particular png_image_read_from_ function you call at the start.
* Likewise, on write, you can write to a FILE* if your system supports it.
* Check the macro PNG_STDIO_SUPPORTED to see if stdio support has been
* included in your libpng build.
*
* If you read 16-bit (PNG_FORMAT_FLAG_LINEAR) data, you may need to write it
* in the 8-bit format for display. You do this by setting the convert_to_8bit
* flag to 'true'.
*
* Don't repeatedly convert between the 8-bit and 16-bit forms. There is
* significant data loss when 16-bit data is converted to the 8-bit encoding,
* and the current libpng implementation of conversion to 16-bit is also
* significantly lossy. The latter will be fixed in the future, but the former
* is unavoidable - the 8-bit format just doesn't have enough resolution.
*/
/* If your program needs more information from the PNG data it reads, or if you
* need to do more complex transformations, or minimize transformations, on the
* data you read, then you must use one of the several lower level libpng
* interfaces.
*
* All these interfaces require that you do your own error handling - your
* program must be able to arrange for control to return to your own code, any
* time libpng encounters a problem. There are several ways to do this, but
* the standard way is to use the <setjmp.h> interface to establish a return
* point within your own code. You must do this if you do not use the
* simplified interface (above).
*
* The first step is to include the header files you need, including the libpng
* header file. Include any standard headers and feature test macros your
* program requires before including png.h:
*/
#include <png.h>
/* The png_jmpbuf() macro, used in error handling, became available in
* libpng version 1.0.6. If you want to be able to run your code with older
* versions of libpng, you must define the macro yourself (but only if it
* is not already defined by libpng!)
*/
#ifndef png_jmpbuf
# define png_jmpbuf(png_ptr) ((png_ptr)->png_jmpbuf)
#endif
/* Check to see if a file is a PNG file using png_sig_cmp(). png_sig_cmp()
* returns zero if the image is a PNG, and nonzero otherwise.
*
* The function check_if_png() shown here, but not used, returns nonzero (true)
* if the file can be opened and is a PNG, and 0 (false) otherwise.
*
* If this call is successful, and you are going to keep the file open,
* you should call png_set_sig_bytes(png_ptr, PNG_BYTES_TO_CHECK); once
* you have created the png_ptr, so that libpng knows your application
* has read that many bytes from the start of the file. Make sure you
* don't call png_set_sig_bytes() with more than 8 bytes read or give it
* an incorrect number of bytes read, or you will either have read too
* many bytes (your fault), or you are telling libpng to read the wrong
* number of magic bytes (also your fault).
*
* Many applications already read the first 2 or 4 bytes from the start
* of the image to determine the file type, so it would be easiest just
* to pass the bytes to png_sig_cmp(), or even skip that if you know
* you have a PNG file, and call png_set_sig_bytes().
*/
#define PNG_BYTES_TO_CHECK 4
int check_if_png(char *file_name, FILE **fp)
{
char buf[PNG_BYTES_TO_CHECK];
/* Open the prospective PNG file. */
if ((*fp = fopen(file_name, "rb")) == NULL)
return 0;
/* Read in some of the signature bytes. */
if (fread(buf, 1, PNG_BYTES_TO_CHECK, *fp) != PNG_BYTES_TO_CHECK)
return 0;
/* Compare the first PNG_BYTES_TO_CHECK bytes of the signature.
* Return nonzero (true) if they match.
*/
return(!png_sig_cmp(buf, 0, PNG_BYTES_TO_CHECK));
}
/* Read a PNG file. You may want to return an error code if the read
* fails (depending upon the failure). There are two "prototypes" given
* here - one where we are given the filename, and we need to open the
* file, and the other where we are given an open file (possibly with
* some or all of the magic bytes read - see comments above).
*/
#ifdef open_file /* prototype 1 */
void read_png(char *file_name) /* We need to open the file */
{
png_structp png_ptr;
png_infop info_ptr;
int sig_read = 0;
png_uint_32 width, height;
int bit_depth, color_type, interlace_type;
FILE *fp;
if ((fp = fopen(file_name, "rb")) == NULL)
return (ERROR);
#else no_open_file /* prototype 2 */
void read_png(FILE *fp, int sig_read) /* File is already open */
{
png_structp png_ptr;
png_infop info_ptr;
png_uint_32 width, height;
int bit_depth, color_type, interlace_type;
#endif no_open_file /* Only use one prototype! */
/* Create and initialize the png_struct with the desired error handler
* functions. If you want to use the default stderr and longjump method,
* you can supply NULL for the last three parameters. We also supply the
* the compiler header file version, so that we know if the application
* was compiled with a compatible version of the library. REQUIRED.
*/
png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,
png_voidp user_error_ptr, user_error_fn, user_warning_fn);
if (png_ptr == NULL)
{
fclose(fp);
return (ERROR);
}
/* Allocate/initialize the memory for image information. REQUIRED. */
info_ptr = png_create_info_struct(png_ptr);
if (info_ptr == NULL)
{
fclose(fp);
png_destroy_read_struct(&png_ptr, NULL, NULL);
return (ERROR);
}
/* Set error handling if you are using the setjmp/longjmp method (this is
* the normal method of doing things with libpng). REQUIRED unless you
* set up your own error handlers in the png_create_read_struct() earlier.
*/
if (setjmp(png_jmpbuf(png_ptr)))
{
/* Free all of the memory associated with the png_ptr and info_ptr. */
png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
fclose(fp);
/* If we get here, we had a problem reading the file. */
return (ERROR);
}
/* One of the following I/O initialization methods is REQUIRED. */
#ifdef streams /* PNG file I/O method 1 */
/* Set up the input control if you are using standard C streams. */
png_init_io(png_ptr, fp);
#else no_streams /* PNG file I/O method 2 */
/* If you are using replacement read functions, instead of calling
* png_init_io(), you would call:
*/
png_set_read_fn(png_ptr, (void *)user_io_ptr, user_read_fn);
/* where user_io_ptr is a structure you want available to the callbacks. */
#endif no_streams /* Use only one I/O method! */
/* If we have already read some of the signature */
png_set_sig_bytes(png_ptr, sig_read);
#ifdef hilevel
/* If you have enough memory to read in the entire image at once,
* and you need to specify only transforms that can be controlled
* with one of the PNG_TRANSFORM_* bits (this presently excludes
* quantizing, filling, setting background, and doing gamma
* adjustment), then you can read the entire image (including
* pixels) into the info structure with this call:
*/
png_read_png(png_ptr, info_ptr, png_transforms, NULL);
#else
/* OK, you're doing it the hard way, with the lower-level functions. */
/* The call to png_read_info() gives us all of the information from the
* PNG file before the first IDAT (image data chunk). REQUIRED.
*/
png_read_info(png_ptr, info_ptr);
png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
&interlace_type, NULL, NULL);
/* Set up the data transformations you want. Note that these are all
* optional. Only call them if you want/need them. Many of the
* transformations only work on specific types of images, and many
* are mutually exclusive.
*/
/* Tell libpng to strip 16 bits/color files down to 8 bits/color.
* Use accurate scaling if it's available, otherwise just chop off the
* low byte.
*/
#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
png_set_scale_16(png_ptr);
#else
png_set_strip_16(png_ptr);
#endif
/* Strip alpha bytes from the input data without combining with the
* background (not recommended).
*/
png_set_strip_alpha(png_ptr);
/* Extract multiple pixels with bit depths of 1, 2 or 4 from a single
* byte into separate bytes (useful for paletted and grayscale images).
*/
png_set_packing(png_ptr);
/* Change the order of packed pixels to least significant bit first
* (not useful if you are using png_set_packing).
*/
png_set_packswap(png_ptr);
/* Expand paletted colors into true RGB triplets. */
if (color_type == PNG_COLOR_TYPE_PALETTE)
png_set_palette_to_rgb(png_ptr);
/* Expand grayscale images to the full 8 bits from 1, 2 or 4 bits/pixel. */
if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
png_set_expand_gray_1_2_4_to_8(png_ptr);
/* Expand paletted or RGB images with transparency to full alpha channels
* so the data will be available as RGBA quartets.
*/
if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS) != 0)
png_set_tRNS_to_alpha(png_ptr);
/* Set the background color to draw transparent and alpha images over.
* It is possible to set the red, green and blue components directly
* for paletted images, instead of supplying a palette index. Note that,
* even if the PNG file supplies a background, you are not required to
* use it - you should use the (solid) application background if it has one.
*/
png_color_16 my_background, *image_background;
if (png_get_bKGD(png_ptr, info_ptr, &image_background) != 0)
png_set_background(png_ptr, image_background,
PNG_BACKGROUND_GAMMA_FILE, 1, 1.0);
else
png_set_background(png_ptr, &my_background,
PNG_BACKGROUND_GAMMA_SCREEN, 0, 1.0);
/* Some suggestions as to how to get a screen gamma value.
*
* Note that screen gamma is the display_exponent, which includes
* the CRT_exponent and any correction for viewing conditions.
*/
if (/* We have a user-defined screen gamma value */)
screen_gamma = user-defined screen_gamma;
/* This is one way that applications share the same screen gamma value. */
else if ((gamma_str = getenv("SCREEN_GAMMA")) != NULL)
screen_gamma = atof(gamma_str);
/* If we don't have another value */
else
{
screen_gamma = PNG_DEFAULT_sRGB; /* A good guess for a PC monitor
in a dimly lit room */
screen_gamma = PNG_GAMMA_MAC_18 or 1.0; /* Good guesses for Mac
systems */
}
/* Tell libpng to handle the gamma conversion for you. The final call
* is a good guess for PC generated images, but it should be configurable
* by the user at run time. Gamma correction support in your application
* is strongly recommended.
*/
int intent;
if (png_get_sRGB(png_ptr, info_ptr, &intent) != 0)
png_set_gamma(png_ptr, screen_gamma, PNG_DEFAULT_sRGB);
else
{
double image_gamma;
if (png_get_gAMA(png_ptr, info_ptr, &image_gamma) != 0)
png_set_gamma(png_ptr, screen_gamma, image_gamma);
else
png_set_gamma(png_ptr, screen_gamma, 0.45455);
}
#ifdef PNG_READ_QUANTIZE_SUPPORTED
/* Quantize RGB files down to 8-bit palette, or reduce palettes
* to the number of colors available on your screen.
*/
if ((color_type & PNG_COLOR_MASK_COLOR) != 0)
{
int num_palette;
png_colorp palette;
/* This reduces the image to the application-supplied palette. */
if (/* We have our own palette */)
{
/* An array of colors to which the image should be quantized. */
png_color std_color_cube[MAX_SCREEN_COLORS];
png_set_quantize(png_ptr, std_color_cube, MAX_SCREEN_COLORS,
MAX_SCREEN_COLORS, NULL, 0);
}
/* This reduces the image to the palette supplied in the file. */
else if (png_get_PLTE(png_ptr, info_ptr, &palette, &num_palette) != 0)
{
png_uint_16p histogram = NULL;
png_get_hIST(png_ptr, info_ptr, &histogram);
png_set_quantize(png_ptr, palette, num_palette,
max_screen_colors, histogram, 0);
}
}
#endif /* READ_QUANTIZE */
/* Invert monochrome files to have 0 as white and 1 as black. */
png_set_invert_mono(png_ptr);
/* If you want to shift the pixel values from the range [0,255] or
* [0,65535] to the original [0,7] or [0,31], or whatever range the
* colors were originally in:
*/
if (png_get_valid(png_ptr, info_ptr, PNG_INFO_sBIT) != 0)
{
png_color_8p sig_bit_p;
png_get_sBIT(png_ptr, info_ptr, &sig_bit_p);
png_set_shift(png_ptr, sig_bit_p);
}
/* Flip the RGB pixels to BGR (or RGBA to BGRA). */
if ((color_type & PNG_COLOR_MASK_COLOR) != 0)
png_set_bgr(png_ptr);
/* Swap the RGBA or GA data to ARGB or AG (or BGRA to ABGR). */
png_set_swap_alpha(png_ptr);
/* Swap bytes of 16-bit files to least significant byte first. */
png_set_swap(png_ptr);
/* Add filler (or alpha) byte (before/after each RGB triplet). */
png_set_filler(png_ptr, 0xffff, PNG_FILLER_AFTER);
#ifdef PNG_READ_INTERLACING_SUPPORTED
/* Turn on interlace handling. REQUIRED if you are not using
* png_read_image(). To see how to handle interlacing passes,
* see the png_read_row() method below:
*/
number_passes = png_set_interlace_handling(png_ptr);
#else /* !READ_INTERLACING */
number_passes = 1;
#endif /* READ_INTERLACING */
/* Optional call to gamma correct and add the background to the palette
* and update info structure. REQUIRED if you are expecting libpng to
* update the palette for you (i.e. you selected such a transform above).
*/
png_read_update_info(png_ptr, info_ptr);
/* Allocate the memory to hold the image using the fields of info_ptr. */
png_bytep row_pointers[height];
for (row = 0; row < height; row++)
row_pointers[row] = NULL; /* Clear the pointer array */
for (row = 0; row < height; row++)
row_pointers[row] = png_malloc(png_ptr, png_get_rowbytes(png_ptr,
info_ptr));
/* Now it's time to read the image. One of these methods is REQUIRED. */
#ifdef entire /* Read the entire image in one go */
png_read_image(png_ptr, row_pointers);
#else no_entire /* Read the image one or more scanlines at a time */
/* The other way to read images - deal with interlacing: */
for (pass = 0; pass < number_passes; pass++)
{
#ifdef single /* Read the image a single row at a time */
for (y = 0; y < height; y++)
png_read_rows(png_ptr, &row_pointers[y], NULL, 1);
#else no_single /* Read the image several rows at a time */
for (y = 0; y < height; y += number_of_rows)
{
#ifdef sparkle /* Read the image using the "sparkle" effect. */
png_read_rows(png_ptr, &row_pointers[y], NULL,
number_of_rows);
#else no_sparkle /* Read the image using the "rectangle" effect */
png_read_rows(png_ptr, NULL, &row_pointers[y],
number_of_rows);
#endif no_sparkle /* Use only one of these two methods */
}
/* If you want to display the image after every pass, do so here. */
#endif no_single /* Use only one of these two methods */
}
#endif no_entire /* Use only one of these two methods */
/* Read rest of file, and get additional chunks in info_ptr. REQUIRED. */
png_read_end(png_ptr, info_ptr);
#endif hilevel
/* At this point you have read the entire image. */
/* Clean up after the read, and free any memory allocated. REQUIRED. */
png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
/* Close the file. */
fclose(fp);
/* That's it! */
return (OK);
}
/* Progressively read a file */
int
initialize_png_reader(png_structp *png_ptr, png_infop *info_ptr)
{
/* Create and initialize the png_struct with the desired error handler
* functions. If you want to use the default stderr and longjump method,
* you can supply NULL for the last three parameters. We also check that
* the library version is compatible, in case we are using dynamically
* linked libraries.
*/
*png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,
png_voidp user_error_ptr, user_error_fn, user_warning_fn);
if (*png_ptr == NULL)
{
*info_ptr = NULL;
return (ERROR);
}
*info_ptr = png_create_info_struct(png_ptr);
if (*info_ptr == NULL)
{
png_destroy_read_struct(png_ptr, info_ptr, NULL);
return (ERROR);
}
if (setjmp(png_jmpbuf((*png_ptr))))
{
png_destroy_read_struct(png_ptr, info_ptr, NULL);
return (ERROR);
}
/* You will need to provide all three function callbacks,
* even if you aren't using all of them.
* If you aren't using all functions, you can specify NULL
* parameters. Even when all three functions are NULL,
* you need to call png_set_progressive_read_fn().
* These functions shouldn't be dependent on global or
* static variables if you are decoding several images
* simultaneously. You should store stream specific data
* in a separate struct, given as the second parameter,
* and retrieve the pointer from inside the callbacks using
* the function png_get_progressive_ptr(png_ptr).
*/
png_set_progressive_read_fn(*png_ptr, (void *)stream_data,
info_callback, row_callback, end_callback);
return (OK);
}
int
process_data(png_structp *png_ptr, png_infop *info_ptr,
png_bytep buffer, png_uint_32 length)
{
if (setjmp(png_jmpbuf((*png_ptr))))
{
/* Free the png_ptr and info_ptr memory on error. */
png_destroy_read_struct(png_ptr, info_ptr, NULL);
return (ERROR);
}
/* Give chunks of data as they arrive from the data stream
* (in order, of course).
* On segmented machines, don't give it any more than 64K.
* The library seems to run fine with sizes of 4K, although
* you can give it much less if necessary. (I assume you can
* give it chunks of 1 byte, but I haven't tried with less
* than 256 bytes yet.) When this function returns, you may
* want to display any rows that were generated in the row
* callback, if you aren't already displaying them there.
*/
png_process_data(*png_ptr, *info_ptr, buffer, length);
return (OK);
}
info_callback(png_structp png_ptr, png_infop info)
{
/* Do any setup here, including setting any of the transformations
* mentioned in the Reading PNG files section. For now, you _must_
* call either png_start_read_image() or png_read_update_info()
* after all the transformations are set (even if you don't set
* any). You may start getting rows before png_process_data()
* returns, so this is your last chance to prepare for that.
*/
}
row_callback(png_structp png_ptr, png_bytep new_row,
png_uint_32 row_num, int pass)
{
/* This function is called for every row in the image. If the
* image is interlaced, and you turned on the interlace handler,
* this function will be called for every row in every pass.
*
* In this function you will receive a pointer to new row data from
* libpng called new_row that is to replace a corresponding row (of
* the same data format) in a buffer allocated by your application.
*
* The new row data pointer "new_row" may be NULL, indicating there is
* no new data to be replaced (in cases of interlace loading).
*
* If new_row is not NULL, then you need to call
* png_progressive_combine_row(), to replace the corresponding row as
* shown below:
*/
/* Get pointer to corresponding row in our PNG read buffer. */
png_bytep old_row = ((png_bytep *)our_data)[row_num];
#ifdef PNG_READ_INTERLACING_SUPPORTED
/* If both rows are allocated, then copy the new row
* data to the corresponding row data.
*/
if (old_row != NULL && new_row != NULL)
png_progressive_combine_row(png_ptr, old_row, new_row);
/* The rows and passes are called in order, so you don't really
* need the row_num and pass, but I'm supplying them because it
* may make your life easier.
*
* For the non-NULL rows of interlaced images, you must call
* png_progressive_combine_row() passing in the new row and the
* old row, as demonstrated above. You can call this function for
* NULL rows (it will just return) and for non-interlaced images
* (it just does the memcpy for you) if it will make the code
* easier. Thus, you can just do this for all cases:
*/
png_progressive_combine_row(png_ptr, old_row, new_row);
/* where old_row is what was displayed for previous rows. Note
* that the first pass (pass == 0 really) will completely cover
* the old row, so the rows do not have to be initialized. After
* the first pass (and only for interlaced images), you will have
* to pass the current row as new_row, and the function will combine
* the old row and the new row.
*/
#endif /* READ_INTERLACING */
}
end_callback(png_structp png_ptr, png_infop info)
{
/* This function is called when the whole image has been read,
* including any chunks after the image (up to and including
* the IEND). You will usually have the same info chunk as you
* had in the header, although some data may have been added
* to the comments and time fields.
*
* Most people won't do much here, perhaps setting a flag that
* marks the image as finished.
*/
}
/* Write a png file */
void write_png(char *file_name /* , ... other image information ... */)
{
FILE *fp;
png_structp png_ptr;
png_infop info_ptr;
png_colorp palette;
/* Open the file */
fp = fopen(file_name, "wb");
if (fp == NULL)
return (ERROR);
/* Create and initialize the png_struct with the desired error handler
* functions. If you want to use the default stderr and longjump method,
* you can supply NULL for the last three parameters. We also check that
* the library version is compatible with the one used at compile time,
* in case we are using dynamically linked libraries. REQUIRED.
*/
png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING,
png_voidp user_error_ptr, user_error_fn, user_warning_fn);
if (png_ptr == NULL)
{
fclose(fp);
return (ERROR);
}
/* Allocate/initialize the image information data. REQUIRED. */
info_ptr = png_create_info_struct(png_ptr);
if (info_ptr == NULL)
{
fclose(fp);
png_destroy_write_struct(&png_ptr, NULL);
return (ERROR);
}
/* Set up error handling. REQUIRED if you aren't supplying your own
* error handling functions in the png_create_write_struct() call.
*/
if (setjmp(png_jmpbuf(png_ptr)))
{
/* If we get here, we had a problem writing the file. */
fclose(fp);
png_destroy_write_struct(&png_ptr, &info_ptr);
return (ERROR);
}
/* One of the following I/O initialization functions is REQUIRED. */
#ifdef streams /* I/O initialization method 1 */
/* Set up the output control if you are using standard C streams. */
png_init_io(png_ptr, fp);
#else no_streams /* I/O initialization method 2 */
/* If you are using replacement write functions, instead of calling
* png_init_io(), you would call:
*/
png_set_write_fn(png_ptr, (void *)user_io_ptr, user_write_fn,
user_IO_flush_function);
/* where user_io_ptr is a structure you want available to the callbacks. */
#endif no_streams /* Only use one initialization method */
#ifdef hilevel
/* This is the easy way. Use it if you already have all the
* image info living in the structure. You could "|" many
* PNG_TRANSFORM flags into the png_transforms integer here.
*/
png_write_png(png_ptr, info_ptr, png_transforms, NULL);
#else
/* This is the hard way. */
/* Set the image information here. Width and height are up to 2^31,
* bit_depth is one of 1, 2, 4, 8 or 16, but valid values also depend on
* the color_type selected. color_type is one of PNG_COLOR_TYPE_GRAY,
* PNG_COLOR_TYPE_GRAY_ALPHA, PNG_COLOR_TYPE_PALETTE, PNG_COLOR_TYPE_RGB,
* or PNG_COLOR_TYPE_RGB_ALPHA. interlace is either PNG_INTERLACE_NONE or
* PNG_INTERLACE_ADAM7, and the compression_type and filter_type MUST
* currently be PNG_COMPRESSION_TYPE_BASE and PNG_FILTER_TYPE_BASE.
* REQUIRED.
*/
png_set_IHDR(png_ptr, info_ptr, width, height, bit_depth,
PNG_COLOR_TYPE_???, PNG_INTERLACE_????,
PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
/* Set the palette if there is one. REQUIRED for indexed-color images. */
palette = (png_colorp)png_malloc(png_ptr,
PNG_MAX_PALETTE_LENGTH * (sizeof (png_color)));
/* ... Set palette colors ... */
png_set_PLTE(png_ptr, info_ptr, palette, PNG_MAX_PALETTE_LENGTH);
/* You must not free palette here, because png_set_PLTE only makes a link
* to the palette that you allocated. Wait until you are about to destroy
* the png structure.
*/
/* Optional significant bit (sBIT) chunk. */
png_color_8 sig_bit;
/* If we are dealing with a grayscale image then */
sig_bit.gray = true_bit_depth;
/* Otherwise, if we are dealing with a color image then */
sig_bit.red = true_red_bit_depth;
sig_bit.green = true_green_bit_depth;
sig_bit.blue = true_blue_bit_depth;
/* If the image has an alpha channel then */
sig_bit.alpha = true_alpha_bit_depth;
png_set_sBIT(png_ptr, info_ptr, &sig_bit);
/* Optional gamma chunk is strongly suggested if you have any guess
* as to the correct gamma of the image.
*/
png_set_gAMA(png_ptr, info_ptr, gamma);
/* Optionally write comments into the image. */
{
png_text text_ptr[3];
char key0[] = "Title";
char text0[] = "Mona Lisa";
text_ptr[0].key = key0;
text_ptr[0].text = text0;
text_ptr[0].compression = PNG_TEXT_COMPRESSION_NONE;
text_ptr[0].itxt_length = 0;
text_ptr[0].lang = NULL;
text_ptr[0].lang_key = NULL;
char key1[] = "Author";
char text1[] = "Leonardo DaVinci";
text_ptr[1].key = key1;
text_ptr[1].text = text1;
text_ptr[1].compression = PNG_TEXT_COMPRESSION_NONE;
text_ptr[1].itxt_length = 0;
text_ptr[1].lang = NULL;
text_ptr[1].lang_key = NULL;
char key2[] = "Description";
char text2[] = "<long text>";
text_ptr[2].key = key2;
text_ptr[2].text = text2;
text_ptr[2].compression = PNG_TEXT_COMPRESSION_zTXt;
text_ptr[2].itxt_length = 0;
text_ptr[2].lang = NULL;
text_ptr[2].lang_key = NULL;
png_set_text(write_ptr, write_info_ptr, text_ptr, 3);
}
/* Other optional chunks like cHRM, bKGD, tRNS, tIME, oFFs, pHYs. */
/* Note that if sRGB is present, the gAMA and cHRM chunks must be ignored
* on read and, if your application chooses to write them, they must
* be written in accordance with the sRGB profile.
*/
/* Write the file header information. REQUIRED. */
png_write_info(png_ptr, info_ptr);
/* If you want, you can write the info in two steps, in case you need to
* write your private chunk ahead of PLTE:
*
* png_write_info_before_PLTE(write_ptr, write_info_ptr);
* write_my_chunk();
* png_write_info(png_ptr, info_ptr);
*
* However, given the level of known- and unknown-chunk support in 1.2.0
* and up, this should no longer be necessary.
*/
/* Once we write out the header, the compression type on the text
* chunk gets changed to PNG_TEXT_COMPRESSION_NONE_WR or
* PNG_TEXT_COMPRESSION_zTXt_WR, so it doesn't get written out again
* at the end.
*/
/* Set up the transformations you want. Note that these are
* all optional. Only call them if you want them.
*/
/* Invert monochrome pixels. */
png_set_invert_mono(png_ptr);
/* Shift the pixels up to a legal bit depth and fill in
* as appropriate to correctly scale the image.
*/
png_set_shift(png_ptr, &sig_bit);
/* Pack pixels into bytes. */
png_set_packing(png_ptr);
/* Swap location of alpha bytes from ARGB to RGBA. */
png_set_swap_alpha(png_ptr);
/* Get rid of filler (OR ALPHA) bytes, pack XRGB/RGBX/ARGB/RGBA into
* RGB (4 channels -> 3 channels). The second parameter is not used.
*/
png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE);
/* Flip BGR pixels to RGB. */
png_set_bgr(png_ptr);
/* Swap bytes of 16-bit files to most significant byte first. */
png_set_swap(png_ptr);
/* Swap bits of 1-bit, 2-bit, 4-bit packed pixel formats. */
png_set_packswap(png_ptr);
/* Turn on interlace handling if you are not using png_write_image(). */
if (interlacing != 0)
number_passes = png_set_interlace_handling(png_ptr);
else
number_passes = 1;
/* The easiest way to write the image (you may have a different memory
* layout, however, so choose what fits your needs best). You need to
* use the first method if you aren't handling interlacing yourself.
*/
png_uint_32 k, height, width;
/* In this example, "image" is a one-dimensional array of bytes. */
/* Guard against integer overflow. */
if (height > PNG_SIZE_MAX / (width * bytes_per_pixel))
png_error(png_ptr, "Image data buffer would be too large");
png_byte image[height * width * bytes_per_pixel];
png_bytep row_pointers[height];
if (height > PNG_UINT_32_MAX / (sizeof (png_bytep)))
png_error(png_ptr, "Image is too tall to process in memory");
/* Set up pointers into your "image" byte array. */
for (k = 0; k < height; k++)
row_pointers[k] = image + k * width * bytes_per_pixel;
/* One of the following output methods is REQUIRED. */
#ifdef entire /* Write out the entire image data in one call */
png_write_image(png_ptr, row_pointers);
/* The other way to write the image - deal with interlacing. */
#else no_entire /* Write out the image data by one or more scanlines */
/* The number of passes is either 1 for non-interlaced images,
* or 7 for interlaced images.
*/
for (pass = 0; pass < number_passes; pass++)
{
/* Write a few rows at a time. */
png_write_rows(png_ptr, &row_pointers[first_row], number_of_rows);
/* If you are only writing one row at a time, this works. */
for (y = 0; y < height; y++)
png_write_rows(png_ptr, &row_pointers[y], 1);
}
#endif no_entire /* Use only one output method */
/* You can write optional chunks like tEXt, zTXt, and tIME at the end
* as well. Shouldn't be necessary in 1.2.0 and up, as all the public
* chunks are supported, and you can use png_set_unknown_chunks() to
* register unknown chunks into the info structure to be written out.
*/
/* It is REQUIRED to call this to finish writing the rest of the file. */
png_write_end(png_ptr, info_ptr);
#endif hilevel
/* If you png_malloced a palette, free it here.
* (Don't free info_ptr->palette, as shown in versions 1.0.5m and earlier of
* this example; if libpng mallocs info_ptr->palette, libpng will free it).
* If you allocated it with malloc() instead of png_malloc(), use free()
* instead of png_free().
*/
png_free(png_ptr, palette);
palette = NULL;
/* Similarly, if you png_malloced any data that you passed in with
* png_set_something(), such as a hist or trans array, free it here,
* when you can be sure that libpng is through with it.
*/
png_free(png_ptr, trans);
trans = NULL;
/* Whenever you use png_free(), it is a good idea to set the pointer to
* NULL in case your application inadvertently tries to png_free() it
* again. When png_free() sees a NULL it returns without action, avoiding
* the double-free problem.
*/
/* Clean up after the write, and free any allocated memory. */
png_destroy_write_struct(&png_ptr, &info_ptr);
/* Close the file. */
fclose(fp);
/* That's it! */
return (OK);
}
#endif /* if 0 */
================================================
FILE: jni/png.c
================================================
/* png.c - location for general purpose libpng functions
*
* Copyright (c) 2018-2019 Cosmin Truta
* Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
* Copyright (c) 1996-1997 Andreas Dilger
* Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
*
* This code is released under the libpng license.
* For conditions of distribution and use, see the disclaimer
* and license in png.h
*/
#include "pngpriv.h"
/* Generate a compiler error if there is an old png.h in the search path. */
typedef png_libpng_version_1_6_37 Your_png_h_is_not_version_1_6_37;
#ifdef __GNUC__
/* The version tests may need to be added to, but the problem warning has
* consistently been fixed in GCC versions which obtain wide-spread release.
* The problem is that many versions of GCC rearrange comparison expressions in
* the optimizer in such a way that the results of the comparison will change
* if signed integer overflow occurs. Such comparisons are not permitted in
* ANSI C90, however GCC isn't clever enough to work out that that do not occur
* below in png_ascii_from_fp and png_muldiv, so it produces a warning with
* -Wextra. Unfortunately this is highly dependent on the optimizer and the
* machine architecture so the warning comes and goes unpredictably and is
* impossible to "fix", even were that a good idea.
*/
#if __GNUC__ == 7 && __GNUC_MINOR__ == 1
#define GCC_STRICT_OVERFLOW 1
#endif /* GNU 7.1.x */
#endif /* GNU */
#ifndef GCC_STRICT_OVERFLOW
#define GCC_STRICT_OVERFLOW 0
#endif
/* Tells libpng that we have already handled the first "num_bytes" bytes
* of the PNG file signature. If the PNG data is embedded into another
* stream we can set num_bytes = 8 so that libpng will not attempt to read
* or write any of the magic bytes before it starts on the IHDR.
*/
#ifdef PNG_READ_SUPPORTED
void PNGAPI
png_set_sig_bytes(png_structrp png_ptr, int num_bytes)
{
unsigned int nb = (unsigned int)num_bytes;
png_debug(1, "in png_set_sig_bytes");
if (png_ptr == NULL)
return;
if (num_bytes < 0)
nb = 0;
if (nb > 8)
png_error(png_ptr, "Too many bytes for PNG signature");
png_ptr->sig_bytes = (png_byte)nb;
}
/* Checks whether the supplied bytes match the PNG signature. We allow
* checking less than the full 8-byte signature so that those apps that
* already read the first few bytes of a file to determine the file type
* can simply check the remaining bytes for extra assurance. Returns
* an integer less than, equal to, or greater than zero if sig is found,
* respectively, to be less than, to match, or be greater than the correct
* PNG signature (this is the same behavior as strcmp, memcmp, etc).
*/
int PNGAPI
png_sig_cmp(png_const_bytep sig, size_t start, size_t num_to_check)
{
png_byte png_signature[8] = {137, 80, 78, 71, 13, 10, 26, 10};
if (num_to_check > 8)
num_to_check = 8;
else if (num_to_check < 1)
return (-1);
if (start > 7)
return (-1);
if (start + num_to_check > 8)
num_to_check = 8 - start;
return ((int)(memcmp(&sig[start], &png_signature[start], num_to_check)));
}
#endif /* READ */
#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
/* Function to allocate memory for zlib */
PNG_FUNCTION(voidpf /* PRIVATE */,
png_zalloc,(voidpf png_ptr, uInt items, uInt size),PNG_ALLOCATED)
{
png_alloc_size_t num_bytes = size;
if (png_ptr == NULL)
return NULL;
if (items >= (~(png_alloc_size_t)0)/size)
{
png_warning (png_voidcast(png_structrp, png_ptr),
"Potential overflow in png_zalloc()");
return NULL;
}
num_bytes *= items;
return png_malloc_warn(png_voidcast(png_structrp, png_ptr), num_bytes);
}
/* Function to free memory for zlib */
void /* PRIVATE */
png_zfree(voidpf png_ptr, voidpf ptr)
{
png_free(png_voidcast(png_const_structrp,png_ptr), ptr);
}
/* Reset the CRC variable to 32 bits of 1's. Care must be taken
* in case CRC is > 32 bits to leave the top bits 0.
*/
void /* PRIVATE */
png_reset_crc(png_structrp png_ptr)
{
/* The cast is safe because the crc is a 32-bit value. */
png_ptr->crc = (png_uint_32)crc32(0, Z_NULL, 0);
}
/* Calculate the CRC over a section of data. We can only pass as
* much data to this routine as the largest single buffer size. We
* also check that this data will actually be used before going to the
* trouble of calculating it.
*/
void /* PRIVATE */
png_calculate_crc(png_structrp png_ptr, png_const_bytep ptr, size_t length)
{
int need_crc = 1;
if (PNG_CHUNK_ANCILLARY(png_ptr->chunk_name) != 0)
{
if ((png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_MASK) ==
(PNG_FLAG_CRC_ANCILLARY_USE | PNG_FLAG_CRC_ANCILLARY_NOWARN))
need_crc = 0;
}
else /* critical */
{
if ((png_ptr->flags & PNG_FLAG_CRC_CRITICAL_IGNORE) != 0)
need_crc = 0;
}
/* 'uLong' is defined in zlib.h as unsigned long; this means that on some
* systems it is a 64-bit value. crc32, however, returns 32 bits so the
* following cast is safe. 'uInt' may be no more than 16 bits, so it is
* necessary to perform a loop here.
*/
if (need_crc != 0 && length > 0)
{
uLong crc = png_ptr->crc; /* Should never issue a warning */
do
{
uInt safe_length = (uInt)length;
#ifndef __COVERITY__
if (safe_length == 0)
safe_length = (uInt)-1; /* evil, but safe */
#endif
crc = crc32(crc, ptr, safe_length);
/* The following should never issue compiler warnings; if they do the
* target system has characteristics that will probably violate other
* assumptions within the libpng code.
*/
ptr += safe_length;
length -= safe_length;
}
while (length > 0);
/* And the following is always safe because the crc is only 32 bits. */
png_ptr->crc = (png_uint_32)crc;
}
}
/* Check a user supplied version number, called from both read and write
* functions that create a png_struct.
*/
int
png_user_version_check(png_structrp png_ptr, png_const_charp user_png_ver)
{
/* Libpng versions 1.0.0 and later are binary compatible if the version
* string matches through the second '.'; we must recompile any
* applications that use any older library version.
*/
if (user_png_ver != NULL)
{
int i = -1;
int found_dots = 0;
do
{
i++;
if (user_png_ver[i] != PNG_LIBPNG_VER_STRING[i])
png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
if (user_png_ver[i] == '.')
found_dots++;
} while (found_dots < 2 && user_png_ver[i] != 0 &&
PNG_LIBPNG_VER_STRING[i] != 0);
}
else
png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
if ((png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH) != 0)
{
#ifdef PNG_WARNINGS_SUPPORTED
size_t pos = 0;
char m[128];
pos = png_safecat(m, (sizeof m), pos,
"Application built with libpng-");
pos = png_safecat(m, (sizeof m), pos, user_png_ver);
pos = png_safecat(m, (sizeof m), pos, " but running with ");
pos = png_safecat(m, (sizeof m), pos, PNG_LIBPNG_VER_STRING);
PNG_UNUSED(pos)
png_warning(png_ptr, m);
#endif
#ifdef PNG_ERROR_NUMBERS_SUPPORTED
png_ptr->flags = 0;
#endif
return 0;
}
/* Success return. */
return 1;
}
/* Generic function to create a png_struct for either read or write - this
* contains the common initialization.
*/
PNG_FUNCTION(png_structp /* PRIVATE */,
png_create_png_struct,(png_const_charp user_png_ver, png_voidp error_ptr,
png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
png_malloc_ptr malloc_fn, png_free_ptr free_fn),PNG_ALLOCATED)
{
png_struct create_struct;
# ifdef PNG_SETJMP_SUPPORTED
jmp_buf create_jmp_buf;
# endif
/* This temporary stack-allocated structure is used to provide a place to
* build enough context to allow the user provided memory allocator (if any)
* to be called.
*/
memset(&create_struct, 0, (sizeof create_struct));
/* Added at libpng-1.2.6 */
# ifdef PNG_USER_LIMITS_SUPPORTED
create_struct.user_width_max = PNG_USER_WIDTH_MAX;
create_struct.user_height_max = PNG_USER_HEIGHT_MAX;
# ifdef PNG_USER_CHUNK_CACHE_MAX
/* Added at libpng-1.2.43 and 1.4.0 */
create_struct.user_chunk_cache_max = PNG_USER_CHUNK_CACHE_MAX;
# endif
# ifdef PNG_USER_CHUNK_MALLOC_MAX
/* Added at libpng-1.2.43 and 1.4.1, required only for read but exists
* in png_struct regardless.
*/
create_struct.user_chunk_malloc_max = PNG_USER_CHUNK_MALLOC_MAX;
# endif
# endif
/* The following two API calls simply set fields in png_struct, so it is safe
* to do them now even though error handling is not yet set up.
*/
# ifdef PNG_USER_MEM_SUPPORTED
png_set_mem_fn(&create_struct, mem_ptr, malloc_fn, free_fn);
# else
PNG_UNUSED(mem_ptr)
PNG_UNUSED(malloc_fn)
PNG_UNUSED(free_fn)
# endif
/* (*error_fn) can return control to the caller after the error_ptr is set,
* this will result in a memory leak unless the error_fn does something
* extremely sophisticated. The design lacks merit but is implicit in the
* API.
*/
png_set_error_fn(&create_struct, error_ptr, error_fn, warn_fn);
# ifdef PNG_SETJMP_SUPPORTED
if (!setjmp(create_jmp_buf))
# endif
{
# ifdef PNG_SETJMP_SUPPORTED
/* Temporarily fake out the longjmp information until we have
* successfully completed this function. This only works if we have
* setjmp() support compiled in, but it is safe - this stuff should
* never happen.
*/
create_struct.jmp_buf_ptr = &create_jmp_buf;
create_struct.jmp_buf_size = 0; /*stack allocation*/
create_struct.longjmp_fn = longjmp;
# endif
/* Call the general version checker (shared with read and write code):
*/
if (png_user_version_check(&create_struct, user_png_ver) != 0)
{
png_structrp png_ptr = png_voidcast(png_structrp,
png_malloc_warn(&create_struct, (sizeof *png_ptr)));
if (png_ptr != NULL)
{
/* png_ptr->zstream holds a back-pointer to the png_struct, so
* this can only be done now:
*/
create_struct.zstream.zalloc = png_zalloc;
create_struct.zstream.zfree = png_zfree;
create_struct.zstream.opaque = png_ptr;
# ifdef PNG_SETJMP_SUPPORTED
/* Eliminate the local error handling: */
create_struct.jmp_buf_ptr = NULL;
create_struct.jmp_buf_size = 0;
create_struct.longjmp_fn = 0;
# endif
*png_ptr = create_struct;
/* This is the successful return point */
return png_ptr;
}
}
}
/* A longjmp because of a bug in the application storage allocator or a
* simple failure to allocate the png_struct.
*/
return NULL;
}
/* Allocate the memory for an info_struct for the application. */
PNG_FUNCTION(png_infop,PNGAPI
png_create_info_struct,(png_const_structrp png_ptr),PNG_ALLOCATED)
{
png_inforp info_ptr;
png_debug(1, "in png_create_info_struct");
if (png_ptr == NULL)
return NULL;
/* Use the internal API that does not (or at least should not) error out, so
* that this call always returns ok. The application typically sets up the
* error handling *after* creating the info_struct because this is the way it
* has always been done in 'example.c'.
*/
info_ptr = png_voidcast(png_inforp, png_malloc_base(png_ptr,
(sizeof *info_ptr)));
if (info_ptr != NULL)
memset(info_ptr, 0, (sizeof *info_ptr));
return info_ptr;
}
/* This function frees the memory associated with a single info struct.
* Normally, one would use either png_destroy_read_struct() or
* png_destroy_write_struct() to free an info struct, but this may be
* useful for some applications. From libpng 1.6.0 this function is also used
* internally to implement the png_info release part of the 'struct' destroy
* APIs. This ensures that all possible approaches free the same data (all of
* it).
*/
void PNGAPI
png_destroy_info_struct(png_const_structrp png_ptr, png_infopp info_ptr_ptr)
{
png_inforp info_ptr = NULL;
png_debug(1, "in png_destroy_info_struct");
if (png_ptr == NULL)
return;
if (info_ptr_ptr != NULL)
info_ptr = *info_ptr_ptr;
if (info_ptr != NULL)
{
/* Do this first in case of an error below; if the app implements its own
* memory management this can lead to png_free calling png_error, which
* will abort this routine and return control to the app error handler.
* An infinite loop may result if it then tries to free the same info
* ptr.
*/
*info_ptr_ptr = NULL;
png_free_data(png_ptr, info_ptr, PNG_FREE_ALL, -1);
memset(info_ptr, 0, (sizeof *info_ptr));
png_free(png_ptr, info_ptr);
}
}
/* Initialize the info structure. This is now an internal function (0.89)
* and applications using it are urged to use png_create_info_struct()
* instead. Use deprecated in 1.6.0, internal use removed (used internally it
* is just a memset).
*
* NOTE: it is almost inconceivable that this API is used because it bypasses
* the user-memory mechanism and the user error handling/warning mechanisms in
* those cases where it does anything other than a memset.
*/
PNG_FUNCTION(void,PNGAPI
png_info_init_3,(png_infopp ptr_ptr, size_t png_info_struct_size),
PNG_DEPRECATED)
{
png_inforp info_ptr = *ptr_ptr;
png_debug(1, "in png_info_init_3");
if (info_ptr == NULL)
return;
if ((sizeof (png_info)) > png_info_struct_size)
{
*ptr_ptr = NULL;
/* The following line is why this API should not be used: */
free(info_ptr);
info_ptr = png_voidcast(png_inforp, png_malloc_base(NULL,
(sizeof *info_ptr)));
if (info_ptr == NULL)
return;
*ptr_ptr = info_ptr;
}
/* Set everything to 0 */
memset(info_ptr, 0, (sizeof *info_ptr));
}
/* The following API is not called internally */
void PNGAPI
png_data_freer(png_const_structrp png_ptr, png_inforp info_ptr,
int freer, png_uint_32 mask)
{
png_debug(1, "in png_data_freer");
if (png_ptr == NULL || info_ptr == NULL)
return;
if (freer == PNG_DESTROY_WILL_FREE_DATA)
info_ptr->free_me |= mask;
else if (freer == PNG_USER_WILL_FREE_DATA)
info_ptr->free_me &= ~mask;
else
png_error(png_ptr, "Unknown freer parameter in png_data_freer");
}
void PNGAPI
png_free_data(png_const_structrp png_ptr, png_inforp info_ptr, png_uint_32 mask,
int num)
{
png_debug(1, "in png_free_data");
if (png_ptr == NULL || info_ptr == NULL)
return;
#ifdef PNG_TEXT_SUPPORTED
/* Free text item num or (if num == -1) all text items */
if (info_ptr->text != NULL &&
((mask & PNG_FREE_TEXT) & info_ptr->free_me) != 0)
{
if (num != -1)
{
png_free(png_ptr, info_ptr->text[num].key);
info_ptr->text[num].key = NULL;
}
else
{
int i;
for (i = 0; i < info_ptr->num_text; i++)
png_free(png_ptr, info_ptr->text[i].key);
png_free(png_ptr, info_ptr->text);
info_ptr->text = NULL;
info_ptr->num_text = 0;
info_ptr->max_text = 0;
}
}
#endif
#ifdef PNG_tRNS_SUPPORTED
/* Free any tRNS entry */
if (((mask & PNG_FREE_TRNS) & info_ptr->free_me) != 0)
{
info_ptr->valid &= ~PNG_INFO_tRNS;
png_free(png_ptr, info_ptr->trans_alpha);
info_ptr->trans_alpha = NULL;
info_ptr->num_trans = 0;
}
#endif
#ifdef PNG_sCAL_SUPPORTED
/* Free any sCAL entry */
if (((mask & PNG_FREE_SCAL) & info_ptr->free_me) != 0)
{
png_free(png_ptr, info_ptr->scal_s_width);
png_free(png_ptr, info_ptr->scal_s_height);
info_ptr->scal_s_width = NULL;
info_ptr->scal_s_height = NULL;
info_ptr->valid &= ~PNG_INFO_sCAL;
}
#endif
#ifdef PNG_pCAL_SUPPORTED
/* Free any pCAL entry */
if (((mask & PNG_FREE_PCAL) & info_ptr->free_me) != 0)
{
png_free(png_ptr, info_ptr->pcal_purpose);
png_free(png_ptr, info_ptr->pcal_units);
info_ptr->pcal_purpose = NULL;
info_ptr->pcal_units = NULL;
if (info_ptr->pcal_params != NULL)
{
int i;
for (i = 0; i < info_ptr->pcal_nparams; i++)
png_free(png_ptr, info_ptr->pcal_params[i]);
png_free(png_ptr, info_ptr->pcal_params);
info_ptr->pcal_params = NULL;
}
info_ptr->valid &= ~PNG_INFO_pCAL;
}
#endif
#ifdef PNG_iCCP_SUPPORTED
/* Free any profile entry */
if (((mask & PNG_FREE_ICCP) & info_ptr->free_me) != 0)
{
png_free(png_ptr, info_ptr->iccp_name);
png_free(png_ptr, info_ptr->iccp_profile);
info_ptr->iccp_name = NULL;
info_ptr->iccp_profile = NULL;
info_ptr->valid &= ~PNG_INFO_iCCP;
}
#endif
#ifdef PNG_sPLT_SUPPORTED
/* Free a given sPLT entry, or (if num == -1) all sPLT entries */
if (info_ptr->splt_palettes != NULL &&
((mask & PNG_FREE_SPLT) & info_ptr->free_me) != 0)
{
if (num != -1)
{
png_free(png_ptr, info_ptr->splt_palettes[num].name);
png_free(png_ptr, info_ptr->splt_palettes[num].entries);
info_ptr->splt_palettes[num].name = NULL;
info_ptr->splt_palettes[num].entries = NULL;
}
else
{
int i;
for (i = 0; i < info_ptr->splt_palettes_num; i++)
{
png_free(png_ptr, info_ptr->splt_palettes[i].name);
png_free(png_ptr, info_ptr->splt_palettes[i].entries);
}
png_free(png_ptr, info_ptr->splt_palettes);
info_ptr->splt_palettes = NULL;
info_ptr->splt_palettes_num = 0;
info_ptr->valid &= ~PNG_INFO_sPLT;
}
}
#endif
#ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
if (info_ptr->unknown_chunks != NULL &&
((mask & PNG_FREE_UNKN) & info_ptr->free_me) != 0)
{
if (num != -1)
{
png_free(png_ptr, info_ptr->unknown_chunks[num].data);
info_ptr->unknown_chunks[num].data = NULL;
}
else
{
int i;
for (i = 0; i < info_ptr->unknown_chunks_num; i++)
png_free(png_ptr, info_ptr->unknown_chunks[i].data);
png_free(png_ptr, info_ptr->unknown_chunks);
info_ptr->unknown_chunks = NULL;
info_ptr->unknown_chunks_num = 0;
}
}
#endif
#ifdef PNG_eXIf_SUPPORTED
/* Free any eXIf entry */
if (((mask & PNG_FREE_EXIF) & info_ptr->free_me) != 0)
{
# ifdef PNG_READ_eXIf_SUPPORTED
if (info_ptr->eXIf_buf)
{
png_free(png_ptr, info_ptr->eXIf_buf);
info_ptr->eXIf_buf = NULL;
}
# endif
if (info_ptr->exif)
{
png_free(png_ptr, info_ptr->exif);
info_ptr->exif = NULL;
}
info_ptr->valid &= ~PNG_INFO_eXIf;
}
#endif
#ifdef PNG_hIST_SUPPORTED
/* Free any hIST entry */
if (((mask & PNG_FREE_HIST) & info_ptr->free_me) != 0)
{
png_free(png_ptr, info_ptr->hist);
info_ptr->hist = NULL;
info_ptr->valid &= ~PNG_INFO_hIST;
}
#endif
/* Free any PLTE entry that was internally allocated */
if (((mask & PNG_FREE_PLTE) & info_ptr->free_me) != 0)
{
png_free(png_ptr, info_ptr->palette);
info_ptr->palette = NULL;
info_ptr->valid &= ~PNG_INFO_PLTE;
info_ptr->num_palette = 0;
}
#ifdef PNG_INFO_IMAGE_SUPPORTED
/* Free any image bits attached to the info structure */
if (((mask & PNG_FREE_ROWS) & info_ptr->free_me) != 0)
{
if (info_ptr->row_pointers != NULL)
{
png_uint_32 row;
for (row = 0; row < info_ptr->height; row++)
png_free(png_ptr, info_ptr->row_pointers[row]);
png_free(png_ptr, info_ptr->row_pointers);
info_ptr->row_pointers = NULL;
}
info_ptr->valid &= ~PNG_INFO_IDAT;
}
#endif
if (num != -1)
mask &= ~PNG_FREE_MUL;
info_ptr->free_me &= ~mask;
}
#endif /* READ || WRITE */
/* This function returns a pointer to the io_ptr associated with the user
* functions. The application should free any memory associated with this
* pointer before png_write_destroy() or png_read_destroy() are called.
*/
png_voidp PNGAPI
png_get_io_ptr(png_const_structrp png_ptr)
{
if (png_ptr == NULL)
return (NULL);
return (png_ptr->io_ptr);
}
#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
# ifdef PNG_STDIO_SUPPORTED
/* Initialize the default input/output functions for the PNG file. If you
* use your own read or write routines, you can call either png_set_read_fn()
* or png_set_write_fn() instead of png_init_io(). If you have defined
* PNG_NO_STDIO or otherwise disabled PNG_STDIO_SUPPORTED, you must use a
* function of your own because "FILE *" isn't necessarily available.
*/
void PNGAPI
png_init_io(png_structrp png_ptr, png_FILE_p fp)
{
png_debug(1, "in png_init_io");
if (png_ptr == NULL)
return;
png_ptr->io_ptr = (png_voidp)fp;
}
# endif
# ifdef PNG_SAVE_INT_32_SUPPORTED
/* PNG signed integers are saved in 32-bit 2's complement format. ANSI C-90
* defines a cast of a signed integer to an unsigned integer either to preserve
* the value, if it is positive, or to calculate:
*
* (UNSIGNED_MAX+1) + integer
*
* Where UNSIGNED_MAX is the appropriate maximum unsigned value, so when the
* negative integral value is added the result will be an unsigned value
* correspnding to the 2's complement representation.
*/
void PNGAPI
png_save_int_32(png_bytep buf, png_int_32 i)
{
png_save_uint_32(buf, (png_uint_32)i);
}
# endif
# ifdef PNG_TIME_RFC1123_SUPPORTED
/* Convert the supplied time into an RFC 1123 string suitable for use in
* a "Creation Time" or other text-based time string.
*/
int PNGAPI
png_convert_to_rfc1123_buffer(char out[29], png_const_timep ptime)
{
static const char short_months[12][4] =
{"Jan", "Feb", "Mar", "Apr", "May", "Jun",
"Jul", "Aug", "Sep", "Oct", "Nov", "Dec"};
if (out == NULL)
return 0;
if (ptime->year > 9999 /* RFC1123 limitation */ ||
ptime->month == 0 || ptime->month > 12 ||
ptime->day == 0 || ptime->day > 31 ||
ptime->hour > 23 || ptime->minute > 59 ||
ptime->second > 60)
return 0;
{
size_t pos = 0;
char number_buf[5]; /* enough for a four-digit year */
# define APPEND_STRING(string) pos = png_safecat(out, 29, pos, (string))
# define APPEND_NUMBER(format, value)\
APPEND_STRING(PNG_FORMAT_NUMBER(number_buf, format, (value)))
# define APPEND(ch) if (pos < 28) out[pos++] = (ch)
APPEND_NUMBER(PNG_NUMBER_FORMAT_u, (unsigned)ptime->day);
APPEND(' ');
APPEND_STRING(short_months[(ptime->month - 1)]);
APPEND(' ');
APPEND_NUMBER(PNG_NUMBER_FORMAT_u, ptime->year);
APPEND(' ');
APPEND_NUMBER(PNG_NUMBER_FORMAT_02u, (unsigned)ptime->hour);
APPEND(':');
APPEND_NUMBER(PNG_NUMBER_FORMAT_02u, (unsigned)ptime->minute);
APPEND(':');
APPEND_NUMBER(PNG_NUMBER_FORMAT_02u, (unsigned)ptime->second);
APPEND_STRING(" +0000"); /* This reliably terminates the buffer */
PNG_UNUSED (pos)
# undef APPEND
# undef APPEND_NUMBER
# undef APPEND_STRING
}
return 1;
}
# if PNG_LIBPNG_VER < 10700
/* To do: remove the following from libpng-1.7 */
/* Original API that uses a private buffer in png_struct.
* Deprecated because it causes png_struct to carry a spurious temporary
* buffer (png_struct::time_buffer), better to have the caller pass this in.
*/
png_const_charp PNGAPI
png_convert_to_rfc1123(png_structrp png_ptr, png_const_timep ptime)
{
if (png_ptr != NULL)
{
/* The only failure above if png_ptr != NULL is from an invalid ptime */
if (png_convert_to_rfc1123_buffer(png_ptr->time_buffer, ptime) == 0)
png_warning(png_ptr, "Ignoring invalid time value");
else
return png_ptr->time_buffer;
}
return NULL;
}
# endif /* LIBPNG_VER < 10700 */
# endif /* TIME_RFC1123 */
#endif /* READ || WRITE */
png_const_charp PNGAPI
png_get_copyright(png_const_structrp png_ptr)
{
PNG_UNUSED(png_ptr) /* Silence compiler warning about unused png_ptr */
#ifdef PNG_STRING_COPYRIGHT
return PNG_STRING_COPYRIGHT
#else
return PNG_STRING_NEWLINE \
"libpng version 1.6.37" PNG_STRING_NEWLINE \
"Copyright (c) 2018-2019 Cosmin Truta" PNG_STRING_NEWLINE \
"Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson" \
PNG_STRING_NEWLINE \
"Copyright (c) 1996-1997 Andreas Dilger" PNG_STRING_NEWLINE \
"Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc." \
PNG_STRING_NEWLINE;
#endif
}
/* The following return the library version as a short string in the
* format 1.0.0 through 99.99.99zz. To get the version of *.h files
* used with your application, print out PNG_LIBPNG_VER_STRING, which
* is defined in png.h.
* Note: now there is no difference between png_get_libpng_ver() and
* png_get_header_ver(). Due to the version_nn_nn_nn typedef guard,
* it is guaranteed that png.c uses the correct version of png.h.
*/
png_const_charp PNGAPI
png_get_libpng_ver(png_const_structrp png_ptr)
{
/* Version of *.c files used when building libpng */
return png_get_header_ver(png_ptr);
}
png_const_charp PNGAPI
png_get_header_ver(png_const_structrp png_ptr)
{
/* Version of *.h files used when building libpng */
PNG_UNUSED(png_ptr) /* Silence compiler warning about unused png_ptr */
return PNG_LIBPNG_VER_STRING;
}
png_const_charp PNGAPI
png_get_header_version(png_const_structrp png_ptr)
{
/* Returns longer string containing both version and date */
PNG_UNUSED(png_ptr) /* Silence compiler warning about unused png_ptr */
#ifdef __STDC__
return PNG_HEADER_VERSION_STRING
# ifndef PNG_READ_SUPPORTED
" (NO READ SUPPORT)"
# endif
PNG_STRING_NEWLINE;
#else
return PNG_HEADER_VERSION_STRING;
#endif
}
#ifdef PNG_BUILD_GRAYSCALE_PALETTE_SUPPORTED
/* NOTE: this routine is not used internally! */
/* Build a grayscale palette. Palette is assumed to be 1 << bit_depth
* large of png_color. This lets grayscale images be treated as
* paletted. Most useful for gamma correction and simplification
* of code. This API is not used internally.
*/
void PNGAPI
png_build_grayscale_palette(int bit_depth, png_colorp palette)
{
int num_palette;
int color_inc;
int i;
int v;
png_debug(1, "in png_do_build_grayscale_palette");
if (palette == NULL)
return;
switch (bit_depth)
{
case 1:
num_palette = 2;
color_inc = 0xff;
break;
case 2:
num_palette = 4;
color_inc = 0x55;
break;
case 4:
num_palette = 16;
color_inc = 0x11;
break;
case 8:
num_palette = 256;
color_inc = 1;
break;
default:
num_palette = 0;
color_inc = 0;
break;
}
for (i = 0, v = 0; i < num_palette; i++, v += color_inc)
{
palette[i].red = (png_byte)(v & 0xff);
palette[i].green = (png_byte)(v & 0xff);
palette[i].blue = (png_byte)(v & 0xff);
}
}
#endif
#ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
int PNGAPI
png_handle_as_unknown(png_const_structrp png_ptr, png_const_bytep chunk_name)
{
/* Check chunk_name and return "keep" value if it's on the list, else 0 */
png_const_bytep p, p_end;
if (png_ptr == NULL || chunk_name == NULL || png_ptr->num_chunk_list == 0)
return PNG_HANDLE_CHUNK_AS_DEFAULT;
p_end = png_ptr->chunk_list;
p = p_end + png_ptr->num_chunk_list*5; /* beyond end */
/* The code is the fifth byte after each four byte string. Historically this
* code was always searched from the end of the list, this is no longer
* necessary because the 'set' routine handles duplicate entries correctly.
*/
do /* num_chunk_list > 0, so at least one */
{
p -= 5;
if (memcmp(chunk_name, p, 4) == 0)
return p[4];
}
while (p > p_end);
/* This means that known chunks should be processed and unknown chunks should
* be handled according to the value of png_ptr->unknown_default; this can be
* confusing because, as a result, there are two levels of defaulting for
* unknown chunks.
*/
return PNG_HANDLE_CHUNK_AS_DEFAULT;
}
#if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED) ||\
defined(PNG_HANDLE_AS_UNKNOWN_SUPPORTED)
int /* PRIVATE */
png_chunk_unknown_handling(png_const_structrp png_ptr, png_uint_32 chunk_name)
{
png_byte chunk_string[5];
PNG_CSTRING_FROM_CHUNK(chunk_string, chunk_name);
return png_handle_as_unknown(png_ptr, chunk_string);
}
#endif /* READ_UNKNOWN_CHUNKS || HANDLE_AS_UNKNOWN */
#endif /* SET_UNKNOWN_CHUNKS */
#ifdef PNG_READ_SUPPORTED
/* This function, added to libpng-1.0.6g, is untested. */
int PNGAPI
png_reset_zstream(png_structrp png_ptr)
{
if (png_ptr == NULL)
return Z_STREAM_ERROR;
/* WARNING: this resets the window bits to the maximum! */
return (inflateReset(&png_ptr->zstream));
}
#endif /* READ */
/* This function was added to libpng-1.0.7 */
png_uint_32 PNGAPI
png_access_version_number(void)
{
/* Version of *.c files used when building libpng */
return((png_uint_32)PNG_LIBPNG_VER);
}
#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
/* Ensure that png_ptr->zstream.msg holds some appropriate error message string.
* If it doesn't 'ret' is used to set it to something appropriate, even in cases
* like Z_OK or Z_STREAM_END where the error code is apparently a success code.
*/
void /* PRIVATE */
png_zstream_error(png_structrp png_ptr, int ret)
{
/* Translate 'ret' into an appropriate error string, priority is given to the
* one in zstream if set. This always returns a string, even in cases like
* Z_OK or Z_STREAM_END where the error code is a success code.
*/
if (png_ptr->zstream.msg == NULL) switch (ret)
{
default:
case Z_OK:
png_ptr->zstream.msg = PNGZ_MSG_CAST("unexpected zlib return code");
break;
case Z_STREAM_END:
/* Normal exit */
png_ptr->zstream.msg = PNGZ_MSG_CAST("unexpected end of LZ stream");
break;
case Z_NEED_DICT:
/* This means the deflate stream did not have a dictionary; this
* indicates a bogus PNG.
*/
png_ptr->zstream.msg = PNGZ_MSG_CAST("missing LZ dictionary");
break;
case Z_ERRNO:
/* gz APIs only: should not happen */
png_ptr->zstream.msg = PNGZ_MSG_CAST("zlib IO error");
break;
case Z_STREAM_ERROR:
/* internal libpng error */
png_ptr->zstream.msg = PNGZ_MSG_CAST("bad parameters to zlib");
break;
case Z_DATA_ERROR:
png_ptr->zstream.msg = PNGZ_MSG_CAST("damaged LZ stream");
break;
case Z_MEM_ERROR:
png_ptr->zstream.msg = PNGZ_MSG_CAST("insufficient memory");
break;
case Z_BUF_ERROR:
/* End of input or output; not a problem if the caller is doing
* incremental read or write.
*/
png_ptr->zstream.msg = PNGZ_MSG_CAST("truncated");
break;
case Z_VERSION_ERROR:
png_ptr->zstream.msg = PNGZ_MSG_CAST("unsupported zlib version");
break;
case PNG_UNEXPECTED_ZLIB_RETURN:
/* Compile errors here mean that zlib now uses the value co-opted in
* pngpriv.h for PNG_UNEXPECTED_ZLIB_RETURN; update the switch above
* and change pngpriv.h. Note that this message is "... return",
* whereas the default/Z_OK one is "... return code".
*/
png_ptr->zstream.msg = PNGZ_MSG_CAST("unexpected zlib return");
break;
}
}
/* png_convert_size: a PNGAPI but no longer in png.h, so deleted
* at libpng 1.5.5!
*/
/* Added at libpng version 1.2.34 and 1.4.0 (moved from pngset.c) */
#ifdef PNG_GAMMA_SUPPORTED /* always set if COLORSPACE */
static int
png_colorspace_check_gamma(png_const_structrp png_ptr,
png_colorspacerp colorspace, png_fixed_point gAMA, int from)
/* This is called to check a new gamma value against an existing one. The
* routine returns false if the new gamma value should not be written.
*
* 'from' says where the new gamma value comes from:
*
* 0: the new gamma value is the libpng estimate for an ICC profile
* 1: the new gamma value comes from a gAMA chunk
* 2: the new gamma value comes from an sRGB chunk
*/
{
png_fixed_point gtest;
if ((colorspace->flags & PNG_COLORSPACE_HAVE_GAMMA) != 0 &&
(png_muldiv(>est, colorspace->gamma, PNG_FP_1, gAMA) == 0 ||
png_gamma_significant(gtest) != 0))
{
/* Either this is an sRGB image, in which case the calculated gamma
* approximation should match, or this is an image with a profile and the
* value libpng calculates for the gamma of the profile does not match the
* value recorded in the file. The former, sRGB, case is an error, the
* latter is just a warning.
*/
if ((colorspace->flags & PNG_COLORSPACE_FROM_sRGB) != 0 || from == 2)
{
png_chunk_report(png_ptr, "gamma value does not match sRGB",
PNG_CHUNK_ERROR);
/* Do not overwrite an sRGB value */
return from == 2;
}
else /* sRGB tag not involved */
{
png_chunk_report(png_ptr, "gamma value does not match libpng estimate",
PNG_CHUNK_WARNING);
return from == 1;
}
}
return 1;
}
void /* PRIVATE */
png_colorspace_set_gamma(png_const_structrp png_ptr,
png_colorspacerp colorspace, png_fixed_point gAMA)
{
/* Changed in libpng-1.5.4 to limit the values to ensure overflow can't
* occur. Since the fixed point representation is asymmetrical it is
* possible for 1/gamma to overflow the limit of 21474 and this means the
* gamma value must be at least 5/100000 and hence at most 20000.0. For
* safety the limits here are a little narrower. The values are 0.00016 to
* 6250.0, which are truly ridiculous gamma values (and will produce
* displays that are all black or all white.)
*
* In 1.6.0 this test replaces the ones in pngrutil.c, in the gAMA chunk
* handling code, which only required the value to be >0.
*/
png_const_charp errmsg;
if (gAMA < 16 || gAMA > 625000000)
errmsg = "gamma value out of range";
# ifdef PNG_READ_gAMA_SUPPORTED
/* Allow the application to set the gamma value more than once */
else if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0 &&
(colorspace->flags & PNG_COLORSPACE_FROM_gAMA) != 0)
errmsg = "duplicate";
# endif
/* Do nothing if the colorspace is already invalid */
else if ((colorspace->flags & PNG_COLORSPACE_INVALID) != 0)
return;
else
{
if (png_colorspace_check_gamma(png_ptr, colorspace, gAMA,
1/*from gAMA*/) != 0)
{
/* Store this gamma value. */
colorspace->gamma = gAMA;
colorspace->flags |=
(PNG_COLORSPACE_HAVE_GAMMA | PNG_COLORSPACE_FROM_gAMA);
}
/* At present if the check_gamma test fails the gamma of the colorspace is
* not updated however the colorspace is not invalidated. This
* corresponds to the case where the existing gamma comes from an sRGB
* chunk or profile. An error message has already been output.
*/
return;
}
/* Error exit - errmsg has been set. */
colorspace->flags |= PNG_COLORSPACE_INVALID;
png_chunk_report(png_ptr, errmsg, PNG_CHUNK_WRITE_ERROR);
}
void /* PRIVATE */
png_colorspace_sync_info(png_const_structrp png_ptr, png_inforp info_ptr)
{
if ((info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) != 0)
{
/* Everything is invalid */
info_ptr->valid &= ~(PNG_INFO_gAMA|PNG_INFO_cHRM|PNG_INFO_sRGB|
PNG_INFO_iCCP);
# ifdef PNG_COLORSPACE_SUPPORTED
/* Clean up the iCCP profile now if it won't be used. */
png_free_data(png_ptr, info_ptr, PNG_FREE_ICCP, -1/*not used*/);
# else
PNG_UNUSED(png_ptr)
# endif
}
else
{
# ifdef PNG_COLORSPACE_SUPPORTED
/* Leave the INFO_iCCP flag set if the pngset.c code has already set
* it; this allows a PNG to contain a profile which matches sRGB and
* yet still have that profile retrievable by the application.
*/
if ((info_ptr->colorspace.flags & PNG_COLORSPACE_MATCHES_sRGB) != 0)
info_ptr->valid |= PNG_INFO_sRGB;
else
info_ptr->valid &= ~PNG_INFO_sRGB;
if ((info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_ENDPOINTS) != 0)
info_ptr->valid |= PNG_INFO_cHRM;
else
info_ptr->valid &= ~PNG_INFO_cHRM;
# endif
if ((info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_GAMMA) != 0)
info_ptr->valid |= PNG_INFO_gAMA;
else
info_ptr->valid &= ~PNG_INFO_gAMA;
}
}
#ifdef PNG_READ_SUPPORTED
void /* PRIVATE */
png_colorspace_sync(png_const_structrp png_ptr, png_inforp info_ptr)
{
if (info_ptr == NULL) /* reduce code size; check here not in the caller */
return;
info_ptr->colorspace = png_ptr->colorspace;
png_colorspace_sync_info(png_ptr, info_ptr);
}
#endif
#endif /* GAMMA */
#ifdef PNG_COLORSPACE_SUPPORTED
/* Added at libpng-1.5.5 to support read and write of true CIEXYZ values for
* cHRM, as opposed to using chromaticities. These internal APIs return
* non-zero on a parameter error. The X, Y and Z values are required to be
* positive and less than 1.0.
*/
static int
png_xy_from_XYZ(png_xy *xy, const png_XYZ *XYZ)
{
png_int_32 d, dwhite, whiteX, whiteY;
d = XYZ->red_X + XYZ->red_Y + XYZ->red_Z;
if (png_muldiv(&xy->redx, XYZ->red_X, PNG_FP_1, d) == 0)
return 1;
if (png_muldiv(&xy->redy, XYZ->red_Y, PNG_FP_1, d) == 0)
return 1;
dwhite = d;
whiteX = XYZ->red_X;
whiteY = XYZ->red_Y;
d = XYZ->green_X + XYZ->green_Y + XYZ->green_Z;
if (png_muldiv(&xy->greenx, XYZ->green_X, PNG_FP_1, d) == 0)
return 1;
if (png_muldiv(&xy->greeny, XYZ->green_Y, PNG_FP_1, d) == 0)
return 1;
dwhite += d;
whiteX += XYZ->green_X;
whiteY += XYZ->green_Y;
d = XYZ->blue_X + XYZ->blue_Y + XYZ->blue_Z;
if (png_muldiv(&xy->bluex, XYZ->blue_X, PNG_FP_1, d) == 0)
return 1;
if (png_muldiv(&xy->bluey, XYZ->blue_Y, PNG_FP_1, d) == 0)
return 1;
dwhite += d;
whiteX += XYZ->blue_X;
whiteY += XYZ->blue_Y;
/* The reference white is simply the sum of the end-point (X,Y,Z) vectors,
* thus:
*/
if (png_muldiv(&xy->whitex, whiteX, PNG_FP_1, dwhite) == 0)
return 1;
if (png_muldiv(&xy->whitey, whiteY, PNG_FP_1, dwhite) == 0)
return 1;
return 0;
}
static int
png_XYZ_from_xy(png_XYZ *XYZ, const png_xy *xy)
{
png_fixed_point red_inverse, green_inverse, blue_scale;
png_fixed_point left, right, denominator;
/* Check xy and, implicitly, z. Note that wide gamut color spaces typically
* have end points with 0 tristimulus values (these are impossible end
* points, but they are used to cover the possible colors). We check
* xy->whitey against 5, not 0, to avoid a possible integer overflow.
*/
if (xy->redx < 0 || xy->redx > PNG_FP_1) return 1;
if (xy->redy < 0 || xy->redy > PNG_FP_1-xy->redx) return 1;
if (xy->greenx < 0 || xy->greenx > PNG_FP_1) return 1;
if (xy->greeny < 0 || xy->greeny > PNG_FP_1-xy->greenx) return 1;
if (xy->bluex < 0 || xy->bluex > PNG_FP_1) return 1;
if (xy->bluey < 0 || xy->bluey > PNG_FP_1-xy->bluex) return 1;
if (xy->whitex < 0 || xy->whitex > PNG_FP_1) return 1;
if (xy->whitey < 5 || xy->whitey > PNG_FP_1-xy->whitex) return 1;
/* The reverse calculation is more difficult because the original tristimulus
* value had 9 independent values (red,green,blue)x(X,Y,Z) however only 8
* derived values were recorded in the cHRM chunk;
* (red,green,blue,white)x(x,y). This loses one degree of freedom and
* therefore an arbitrary ninth value has to be introduced to undo the
* original transformations.
*
* Think of the original end-points as points in (X,Y,Z) space. The
* chromaticity values (c) have the property:
*
* C
* c = ---------
* X + Y + Z
*
* For each c (x,y,z) from the corresponding original C (X,Y,Z). Thus the
* three chromaticity values (x,y,z) for each end-point obey the
* relationship:
*
* x + y + z = 1
*
* This describes the plane in (X,Y,Z) space that intersects each axis at the
* value 1.0; call this the chromaticity plane. Thus the chromaticity
* calculation has scaled each end-point so that it is on the x+y+z=1 plane
* and chromaticity is the intersection of the vector from the origin to the
* (X,Y,Z) value with the chromaticity plane.
*
* To fully invert the chromaticity calculation we would need the three
* end-point scale factors, (red-scale, green-scale, blue-scale), but these
* were not recorded. Instead we calculated the reference white (X,Y,Z) and
* recorded the chromaticity of this. The reference white (X,Y,Z) would have
* given all three of the scale factors since:
*
* color-C = color-c * color-scale
* white-C = red-C + green-C + blue-C
* = red-c*red-scale + green-c*green-scale + blue-c*blue-scale
*
* But cHRM records only white-x and white-y, so we have lost the white scale
* factor:
*
* white-C = white-c*white-scale
*
* To handle this the inverse transformation makes an arbitrary assumption
* about white-scale:
*
* Assume: white-Y = 1.0
* Hence: white-scale = 1/white-y
* Or: red-Y + green-Y + blue-Y = 1.0
*
* Notice the last statement of the assumption gives an equation in three of
* the nine values we want to calculate. 8 more equations come from the
* above routine as summarised at the top above (the chromaticity
* calculation):
*
* Given: color-x = color-X / (color-X + color-Y + color-Z)
* Hence: (color-x - 1)*color-X + color.x*color-Y + color.x*color-Z = 0
*
* This is 9 simultaneous equations in the 9 variables "color-C" and can be
* solved by Cramer's rule. Cramer's rule requires calculating 10 9x9 matrix
* determinants, however this is not as bad as it seems because only 28 of
* the total of 90 terms in the various matrices are non-zero. Nevertheless
* Cramer's rule is notoriously numerically unstable because the determinant
* calculation involves the difference of large, but similar, numbers. It is
* difficult to be sure that the calculation is stable for real world values
* and it is certain that it becomes unstable where the end points are close
* together.
*
* So this code uses the perhaps slightly less optimal but more
* understandable and totally obvious approach of calculating color-scale.
*
* This algorithm depends on the precision in white-scale and that is
* (1/white-y), so we can immediately see that as white-y approaches 0 the
* accuracy inherent in the cHRM chunk drops off substantially.
*
* libpng arithmetic: a simple inversion of the above equations
* ------------------------------------------------------------
*
* white_scale = 1/white-y
* white-X = white-x * white-scale
* white-Y = 1.0
* white-Z = (1 - white-x - white-y) * white_scale
*
* white-C = red-C + green-C + blue-C
* = red-c*red-scale + green-c*green-scale + blue-c*blue-scale
*
* This gives us three equations in (red-scale,green-scale,blue-scale) where
* all the coefficients are now known:
*
* red-x*red-scale + green-x*green-scale + blue-x*blue-scale
* = white-x/white-y
* red-y*red-scale + green-y*green-scale + blue-y*blue-scale = 1
* red-z*red-scale + green-z*green-scale + blue-z*blue-scale
* = (1 - white-x - white-y)/white-y
*
* In the last equation color-z is (1 - color-x - color-y) so we can add all
* three equations together to get an alternative third:
*
* red-scale + green-scale + blue-scale = 1/white-y = white-scale
*
* So now we have a Cramer's rule solution where the determinants are just
* 3x3 - far more tractible. Unfortunately 3x3 determinants still involve
* multiplication of three coefficients so we can't guarantee to avoid
* overflow in the libpng fixed point representation. Using Cramer's rule in
* floating point is probably a good choice here, but it's not an option for
* fixed point. Instead proceed to simplify the first two equations by
* eliminating what is likely to be the largest value, blue-scale:
*
* blue-scale = white-scale - red-scale - green-scale
*
* Hence:
*
* (red-x - blue-x)*red-scale + (green-x - blue-x)*green-scale =
* (white-x - blue-x)*white-scale
*
* (red-y - blue-y)*red-scale + (green-y - blue-y)*green-scale =
* 1 - blue-y*white-scale
*
* And now we can trivially solve for (red-scale,green-scale):
*
* green-scale =
* (white-x - blue-x)*white-scale - (red-x - blue-x)*red-scale
* -----------------------------------------------------------
* green-x - blue-x
*
* red-scale =
* 1 - blue-y*white-scale - (green-y - blue-y) * green-scale
* ---------------------------------------------------------
* red-y - blue-y
*
* Hence:
*
* red-scale =
* ( (green-x - blue-x) * (white-y - blue-y) -
* (green-y - blue-y) * (white-x - blue-x) ) / white-y
* -------------------------------------------------------------------------
* (green-x - blue-x)*(red-y - blue-y)-(green-y - blue-y)*(red-x - blue-x)
*
* green-scale =
* ( (red-y - blue-y) * (white-x - blue-x) -
* (red-x - blue-x) * (white-y - blue-y) ) / white-y
* -------------------------------------------------------------------------
* (green-x - blue-x)*(red-y - blue-y)-(green-y - blue-y)*(red-x - blue-x)
*
* Accuracy:
* The input values have 5 decimal digits of accuracy. The values are all in
* the range 0 < value < 1, so simple products are in the same range but may
* need up to 10 decimal digits to preserve the original precision and avoid
* underflow. Because we are using a 32-bit signed representation we cannot
* match this; the best is a little over 9 decimal digits, less than 10.
*
* The approach used here is to preserve the maximum precision within the
* signed representation. Because the red-scale calculation above uses the
* difference between two products of values that must be in the range -1..+1
* it is sufficient to divide the product by 7; ceil(100,000/32767*2). The
* factor is irrelevant in the calculation because it is applied to both
* numerator and denominator.
*
* Note that the values of the differences of the products of the
* chromaticities in the above equations tend to be small, for example for
* the sRGB chromaticities they are:
*
* red numerator: -0.04751
* green numerator: -0.08788
* denominator: -0.2241 (without white-y multiplication)
*
* The resultant Y coefficients from the chromaticities of some widely used
* color space definitions are (to 15 decimal places):
*
* sRGB
* 0.212639005871510 0.715168678767756 0.072192315360734
* Kodak ProPhoto
* 0.288071128229293 0.711843217810102 0.000085653960605
* Adobe RGB
* 0.297344975250536 0.627363566255466 0.075291458493998
* Adobe Wide Gamut RGB
* 0.258728243040113 0.724682314948566 0.016589442011321
*/
/* By the argument, above overflow should be impossible here. The return
* value of 2 indicates an internal error to the caller.
*/
if (png_muldiv(&left, xy->greenx-xy->bluex, xy->redy - xy->bluey, 7) == 0)
return 2;
if (png_muldiv(&right, xy->greeny-xy->bluey, xy->redx - xy->bluex, 7) == 0)
return 2;
denominator = left - right;
/* Now find the red numerator. */
if (png_muldiv(&left, xy->greenx-xy->bluex, xy->whitey-xy->bluey, 7) == 0)
return 2;
if (png_muldiv(&right, xy->greeny-xy->bluey, xy->whitex-xy->bluex, 7) == 0)
return 2;
/* Overflow is possible here and it indicates an extreme set of PNG cHRM
* chunk values. This calculation actually returns the reciprocal of the
* scale value because this allows us to delay the multiplication of white-y
* into the denominator, which tends to produce a small number.
*/
if (png_muldiv(&red_inverse, xy->whitey, denominator, left-right) == 0 ||
red_inverse <= xy->whitey /* r+g+b scales = white scale */)
return 1;
/* Similarly for green_inverse: */
if (png_muldiv(&left, xy->redy-xy->bluey, xy->whitex-xy->bluex, 7) == 0)
return 2;
if (png_muldiv(&right, xy->redx-xy->bluex, xy->whitey-xy->bluey, 7) == 0)
return 2;
if (png_muldiv(&green_inverse, xy->whitey, denominator, left-right) == 0 ||
green_inverse <= xy->whitey)
return 1;
/* And the blue scale, the checks above guarantee this can't overflow but it
* can still produce 0 for extreme cHRM values.
*/
blue_scale = png_reciprocal(xy->whitey) - png_reciprocal(red_inverse) -
png_reciprocal(green_inverse);
if (blue_scale <= 0)
return 1;
/* And fill in the png_XYZ: */
if (png_muldiv(&XYZ->red_X, xy->redx, PNG_FP_1, red_inverse) == 0)
return 1;
if (png_muldiv(&XYZ->red_Y, xy->redy, PNG_FP_1, red_inverse) == 0)
return 1;
if (png_muldiv(&XYZ->red_Z, PNG_FP_1 - xy->redx - xy->redy, PNG_FP_1,
red_inverse) == 0)
return 1;
if (png_muldiv(&XYZ->green_X, xy->greenx, PNG_FP_1, green_inverse) == 0)
return 1;
if (png_muldiv(&XYZ->green_Y, xy->greeny, PNG_FP_1, green_inverse) == 0)
return 1;
if (png_muldiv(&XYZ->green_Z, PNG_FP_1 - xy->greenx - xy->greeny, PNG_FP_1,
green_inverse) == 0)
return 1;
if (png_muldiv(&XYZ->blue_X, xy->bluex, blue_scale, PNG_FP_1) == 0)
return 1;
if (png_muldiv(&XYZ->blue_Y, xy->bluey, blue_scale, PNG_FP_1) == 0)
return 1;
if (png_muldiv(&XYZ->blue_Z, PNG_FP_1 - xy->bluex - xy->bluey, blue_scale,
PNG_FP_1) == 0)
return 1;
return 0; /*success*/
}
static int
png_XYZ_normalize(png_XYZ *XYZ)
{
png_int_32 Y;
if (XYZ->red_Y < 0 || XYZ->green_Y < 0 || XYZ->blue_Y < 0 ||
XYZ->red_X < 0 || XYZ->green_X < 0 || XYZ->blue_X < 0 ||
XYZ->red_Z < 0 || XYZ->green_Z < 0 || XYZ->blue_Z < 0)
return 1;
/* Normalize by scaling so the sum of the end-point Y values is PNG_FP_1.
* IMPLEMENTATION NOTE: ANSI requires signed overflow not to occur, therefore
* relying on addition of two positive values producing a negative one is not
* safe.
*/
Y = XYZ->red_Y;
if (0x7fffffff - Y < XYZ->green_X)
return 1;
Y += XYZ->green_Y;
if (0x7fffffff - Y < XYZ->blue_X)
return 1;
Y += XYZ->blue_Y;
if (Y != PNG_FP_1)
{
if (png_muldiv(&XYZ->red_X, XYZ->red_X, PNG_FP_1, Y) == 0)
return 1;
if (png_muldiv(&XYZ->red_Y, XYZ->red_Y, PNG_FP_1, Y) == 0)
return 1;
if (png_muldiv(&XYZ->red_Z, XYZ->red_Z, PNG_FP_1, Y) == 0)
return 1;
if (png_muldiv(&XYZ->green_X, XYZ->green_X, PNG_FP_1, Y) == 0)
return 1;
if (png_muldiv(&XYZ->green_Y, XYZ->green_Y, PNG_FP_1, Y) == 0)
return 1;
if (png_muldiv(&XYZ->green_Z, XYZ->green_Z, PNG_FP_1, Y) == 0)
return 1;
if (png_muldiv(&XYZ->blue_X, XYZ->blue_X, PNG_FP_1, Y) == 0)
return 1;
if (png_muldiv(&XYZ->blue_Y, XYZ->blue_Y, PNG_FP_1, Y) == 0)
return 1;
if (png_muldiv(&XYZ->blue_Z, XYZ->blue_Z, PNG_FP_1, Y) == 0)
return 1;
}
return 0;
}
static int
png_colorspace_endpoints_match(const png_xy *xy1, const png_xy *xy2, int delta)
{
/* Allow an error of +/-0.01 (absolute value) on each chromaticity */
if (PNG_OUT_OF_RANGE(xy1->whitex, xy2->whitex,delta) ||
PNG_OUT_OF_RANGE(xy1->whitey, xy2->whitey,delta) ||
PNG_OUT_OF_RANGE(xy1->redx, xy2->redx, delta) ||
PNG_OUT_OF_RANGE(xy1->redy, xy2->redy, delta) ||
PNG_OUT_OF_RANGE(xy1->greenx, xy2->greenx,delta) ||
PNG_OUT_OF_RANGE(xy1->greeny, xy2->greeny,delta) ||
PNG_OUT_OF_RANGE(xy1->bluex, xy2->bluex, delta) ||
PNG_OUT_OF_RANGE(xy1->bluey, xy2->bluey, delta))
return 0;
return 1;
}
/* Added in libpng-1.6.0, a different check for the validity of a set of cHRM
* chunk chromaticities. Earlier checks used to simply look for the overflow
* condition (where the determinant of the matrix to solve for XYZ ends up zero
* because the chromaticity values are not all distinct.) Despite this it is
* theoretically possible to produce chromaticities that are apparently valid
* but that rapidly degrade to invalid, potentially crashing, sets because of
* arithmetic inaccuracies when calculations are performed on them. The new
* check is to round-trip xy -> XYZ -> xy and then check that the result is
* within a small percentage of the original.
*/
static int
png_colorspace_check_xy(png_XYZ *XYZ, const png_xy *xy)
{
int result;
png_xy xy_test;
/* As a side-effect this routine also returns the XYZ endpoints. */
result = png_XYZ_from_xy(XYZ, xy);
if (result != 0)
return result;
result = png_xy_from_XYZ(&xy_test, XYZ);
if (result != 0)
return result;
if (png_colorspace_endpoints_match(xy, &xy_test,
5/*actually, the math is pretty accurate*/) != 0)
return 0;
/* Too much slip */
return 1;
}
/* This is the check going the other way. The XYZ is modified to normalize it
* (another side-effect) and the xy chromaticities are returned.
*/
static int
png_colorspace_check_XYZ(png_xy *xy, png_XYZ *XYZ)
{
int result;
png_XYZ XYZtemp;
result = png_XYZ_normalize(XYZ);
if (result != 0)
return result;
result = png_xy_from_XYZ(xy, XYZ);
if (result != 0)
return result;
XYZtemp = *XYZ;
return png_colorspace_check_xy(&XYZtemp, xy);
}
/* Used to check for an endpoint match against sRGB */
static const png_xy sRGB_xy = /* From ITU-R BT.709-3 */
{
/* color x y */
/* red */ 64000, 33000,
/* green */ 30000, 60000,
/* blue */ 15000, 6000,
/* white */ 31270, 32900
};
static int
png_colorspace_set_xy_and_XYZ(png_const_structrp png_ptr,
png_colorspacerp colorspace, const png_xy *xy, const png_XYZ *XYZ,
int preferred)
{
if ((colorspace->flags & PNG_COLORSPACE_INVALID) != 0)
return 0;
/* The consistency check is performed on the chromaticities; this factors out
* variations because of the normalization (or not) of the end point Y
* values.
*/
if (preferred < 2 &&
(colorspace->flags & PNG_COLORSPACE_HAVE_ENDPOINTS) != 0)
{
/* The end points must be reasonably close to any we already have. The
* following allows an error of up to +/-.001
*/
if (png_colorspace_endpoints_match(xy, &colorspace->end_points_xy,
100) == 0)
{
colorspace->flags |= PNG_COLORSPACE_INVALID;
png_benign_error(png_ptr, "inconsistent chromaticities");
return 0; /* failed */
}
/* Only overwrite with preferred values */
if (preferred == 0)
return 1; /* ok, but no change */
}
colorspace->end_points_xy = *xy;
colorspace->end_points_XYZ = *XYZ;
colorspace->flags |= PNG_COLORSPACE_HAVE_ENDPOINTS;
/* The end points are normally quoted to two decimal digits, so allow +/-0.01
* on this test.
*/
if (png_colorspace_endpoints_match(xy, &sRGB_xy, 1000) != 0)
colorspace->flags |= PNG_COLORSPACE_ENDPOINTS_MATCH_sRGB;
else
colorspace->flags &= PNG_COLORSPACE_CANCEL(
PNG_COLORSPACE_ENDPOINTS_MATCH_sRGB);
return 2; /* ok and changed */
}
int /* PRIVATE */
png_colorspace_set_chromaticities(png_const_structrp png_ptr,
png_colorspacerp colorspace, const png_xy *xy, int preferred)
{
/* We must check the end points to ensure they are reasonable - in the past
* color management systems have crashed as a result of getting bogus
* colorant values, while this isn't the fault of libpng it is the
* responsibility of libpng because PNG carries the bomb and libpng is in a
* position to protect against it.
*/
png_XYZ XYZ;
switch (png_colorspace_check_xy(&XYZ, xy))
{
case 0: /* success */
return png_colorspace_set_xy_and_XYZ(png_ptr, colorspace, xy, &XYZ,
preferred);
case 1:
/* We can't invert the chromaticities so we can't produce value XYZ
* values. Likely as not a color management system will fail too.
*/
colorspace->flags |= PNG_COLORSPACE_INVALID;
png_benign_error(png_ptr, "invalid chromaticities");
break;
default:
/* libpng is broken; this should be a warning but if it happens we
* want error reports so for the moment it is an error.
*/
colorspace->flags |= PNG_COLORSPACE_INVALID;
png_error(png_ptr, "internal error checking chromaticities");
}
return 0; /* failed */
}
int /* PRIVATE */
png_colorspace_set_endpoints(png_const_structrp png_ptr,
png_colorspacerp colorspace, const png_XYZ *XYZ_in, int preferred)
{
png_XYZ XYZ = *XYZ_in;
png_xy xy;
switch (png_colorspace_check_XYZ(&xy, &XYZ))
{
case 0:
return png_colorspace_set_xy_and_XYZ(png_ptr, colorspace, &xy, &XYZ,
preferred);
case 1:
/* End points are invalid. */
colorspace->flags |= PNG_COLORSPACE_INVALID;
png_benign_error(png_ptr, "invalid end points");
break;
default:
colorspace->flags |= PNG_COLORSPACE_INVALID;
png_error(png_ptr, "internal error checking chromaticities");
}
return 0; /* failed */
}
#if defined(PNG_sRGB_SUPPORTED) || defined(PNG_iCCP_SUPPORTED)
/* Error message generation */
static char
png_icc_tag_char(png_uint_32 byte)
{
byte &= 0xff;
if (byte >= 32 && byte <= 126)
return (char)byte;
else
return '?';
}
static void
png_icc_tag_name(char *name, png_uint_32 tag)
{
name[0] = '\'';
name[1] = png_icc_tag_char(tag >> 24);
name[2] = png_icc_tag_char(tag >> 16);
name[3] = png_icc_tag_char(tag >> 8);
name[4] = png_icc_tag_char(tag );
name[5] = '\'';
}
static int
is_ICC_signature_char(png_alloc_size_t it)
{
return it == 32 || (it >= 48 && it <= 57) || (it >= 65 && it <= 90) ||
(it >= 97 && it <= 122);
}
static int
is_ICC_signature(png_alloc_size_t it)
{
return is_ICC_signature_char(it >> 24) /* checks all the top bits */ &&
is_ICC_signature_char((it >> 16) & 0xff) &&
is_ICC_signature_char((it >> 8) & 0xff) &&
is_ICC_signature_char(it & 0xff);
}
static int
png_icc_profile_error(png_const_structrp png_ptr, png_colorspacerp colorspace,
png_const_charp name, png_alloc_size_t value, png_const_charp reason)
{
size_t pos;
char message[196]; /* see below for calculation */
if (colorspace != NULL)
colorspace->flags |= PNG_COLORSPACE_INVALID;
pos = png_safecat(message, (sizeof message), 0, "profile '"); /* 9 chars */
pos = png_safecat(message, pos+79, pos, name); /* Truncate to 79 chars */
pos = png_safecat(message, (sizeof message), pos, "': "); /* +2 = 90 */
if (is_ICC_signature(value) != 0)
{
/* So 'value' is at most 4 bytes and the following cast is safe */
png_icc_tag_name(message+pos, (png_uint_32)value);
pos += 6; /* total +8; less than the else clause */
message[pos++] = ':';
message[pos++] = ' ';
}
# ifdef PNG_WARNINGS_SUPPORTED
else
{
char number[PNG_NUMBER_BUFFER_SIZE]; /* +24 = 114*/
pos = png_safecat(message, (sizeof message), pos,
png_format_number(number, number+(sizeof number),
PNG_NUMBER_FORMAT_x, value));
pos = png_safecat(message, (sizeof message), pos, "h: "); /*+2 = 116*/
}
# endif
/* The 'reason' is an arbitrary message, allow +79 maximum 195 */
pos = png_safecat(message, (sizeof message), pos, reason);
PNG_UNUSED(pos)
/* This is recoverable, but make it unconditionally an app_error on write to
* avoid writing invalid ICC profiles into PNG files (i.e., we handle them
* on read, with a warning, but on write unless the app turns off
* application errors the PNG won't be written.)
*/
png_chunk_report(png_ptr, message,
(colorspace != NULL) ? PNG_CHUNK_ERROR : PNG_CHUNK_WRITE_ERROR);
return 0;
}
#endif /* sRGB || iCCP */
#ifdef PNG_sRGB_SUPPORTED
int /* PRIVATE */
png_colorspace_set_sRGB(png_const_structrp png_ptr, png_colorspacerp colorspace,
int intent)
{
/* sRGB sets known gamma, end points and (from the chunk) intent. */
/* IMPORTANT: these are not necessarily the values found in an ICC profile
* because ICC profiles store values adapted to a D50 environment; it is
* expected that the ICC profile mediaWhitePointTag will be D50; see the
* checks and code elsewhere to understand this better.
*
* These XYZ values, which are accurate to 5dp, produce rgb to gray
* coefficients of (6968,23435,2366), which are reduced (because they add up
* to 32769 not 32768) to (6968,23434,2366). These are the values that
* libpng has traditionally used (and are the best values given the 15bit
* algorithm used by the rgb to gray code.)
*/
static const png_XYZ sRGB_XYZ = /* D65 XYZ (*not* the D50 adapted values!) */
{
/* color X Y Z */
/* red */ 41239, 21264, 1933,
/* green */ 35758, 71517, 11919,
/* blue */ 18048, 7219, 95053
};
/* Do nothing if the colorspace is already invalidated. */
if ((colorspace->flags & PNG_COLORSPACE_INVALID) != 0)
return 0;
/* Check the intent, then check for existing settings. It is valid for the
* PNG file to have cHRM or gAMA chunks along with sRGB, but the values must
* be consistent with the correct values. If, however, this function is
* called below because an iCCP chunk matches sRGB then it is quite
* conceivable that an older app recorded incorrect gAMA and cHRM because of
* an incorrect calculation based on the values in the profile - this does
* *not* invalidate the profile (though it still produces an error, which can
* be ignored.)
*/
if (intent < 0 || intent >= PNG_sRGB_INTENT_LAST)
return png_icc_profile_error(png_ptr, colorspace, "sRGB",
(png_alloc_size_t)intent, "invalid sRGB rendering intent");
if ((colorspace->flags & PNG_COLORSPACE_HAVE_INTENT) != 0 &&
colorspace->rendering_intent != intent)
return png_icc_profile_error(png_ptr, colorspace, "sRGB",
(png_alloc_size_t)intent, "inconsistent rendering intents");
if ((colorspace->flags & PNG_COLORSPACE_FROM_sRGB) != 0)
{
png_benign_error(png_ptr, "duplicate sRGB information ignored");
return 0;
}
/* If the standard sRGB cHRM chunk does not match the one from the PNG file
* warn but overwrite the value with the correct one.
*/
if ((colorspace->flags & PNG_COLORSPACE_HAVE_ENDPOINTS) != 0 &&
!png_colorspace_endpoints_match(&sRGB_xy, &colorspace->end_points_xy,
100))
png_chunk_report(png_ptr, "cHRM chunk does not match sRGB",
PNG_CHUNK_ERROR);
/* This check is just done for the error reporting - the routine always
* returns true when the 'from' argument corresponds to sRGB (2).
*/
(void)png_colorspace_check_gamma(png_ptr, colorspace, PNG_GAMMA_sRGB_INVERSE,
2/*from sRGB*/);
/* intent: bugs in GCC force 'int' to be used as the parameter type. */
colorspace->rendering_intent = (png_uint_16)intent;
colorspace->flags |= PNG_COLORSPACE_HAVE_INTENT;
/* endpoints */
colorspace->end_points_xy = sRGB_xy;
colorspace->end_points_XYZ = sRGB_XYZ;
colorspace->flags |=
(PNG_COLORSPACE_HAVE_ENDPOINTS|PNG_COLORSPACE_ENDPOINTS_MATCH_sRGB);
/* gamma */
colorspace->gamma = PNG_GAMMA_sRGB_INVERSE;
colorspace->flags |= PNG_COLORSPACE_HAVE_GAMMA;
/* Finally record that we have an sRGB profile */
colorspace->flags |=
(PNG_COLORSPACE_MATCHES_sRGB|PNG_COLORSPACE_FROM_sRGB);
return 1; /* set */
}
#endif /* sRGB */
#ifdef PNG_iCCP_SUPPORTED
/* Encoded value of D50 as an ICC XYZNumber. From the ICC 2010 spec the value
* is XYZ(0.9642,1.0,0.8249), which scales to:
*
* (63189.8112, 65536, 54060.6464)
*/
static const png_byte D50_nCIEXYZ[12] =
{ 0x00, 0x00, 0xf6, 0xd6, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0xd3, 0x2d };
static int /* bool */
icc_check_length(png_const_structrp png_ptr, png_colorspacerp colorspace,
png_const_charp name, png_uint_32 profile_length)
{
if (profile_length < 132)
return png_icc_profile_error(png_ptr, colorspace, name, profile_length,
"too short");
return 1;
}
#ifdef PNG_READ_iCCP_SUPPORTED
int /* PRIVATE */
png_icc_check_length(png_const_structrp png_ptr, png_colorspacerp colorspace,
png_const_charp name, png_uint_32 profile_length)
{
if (!icc_check_length(png_ptr, colorspace, name, profile_length))
return 0;
/* This needs to be here because the 'normal' check is in
* png_decompress_chunk, yet this happens after the attempt to
* png_malloc_base the required data. We only need this on read; on write
* the caller supplies the profile buffer so libpng doesn't allocate it. See
* the call to icc_check_length below (the write case).
*/
# ifdef PNG_SET_USER_LIMITS_SUPPORTED
else if (png_ptr->user_chunk_malloc_max > 0 &&
png_ptr->user_chunk_malloc_max < profile_length)
return png_icc_profile_error(png_ptr, colorspace, name, profile_length,
"exceeds application limits");
# elif PNG_USER_CHUNK_MALLOC_MAX > 0
else if (PNG_USER_CHUNK_MALLOC_MAX < profile_length)
return png_icc_profile_error(png_ptr, colorspace, name, profile_length,
"exceeds libpng limits");
# else /* !SET_USER_LIMITS */
/* This will get compiled out on all 32-bit and better systems. */
else if (PNG_SIZE_MAX < profile_length)
return png_icc_profile_error(png_ptr, colorspace, name, profile_length,
"exceeds system limits");
# endif /* !SET_USER_LIMITS */
return 1;
}
#endif /* READ_iCCP */
int /* PRIVATE */
png_icc_check_header(png_const_structrp png_ptr, png_colorspacerp colorspace,
png_const_charp name, png_uint_32 profile_length,
png_const_bytep profile/* first 132 bytes only */, int color_type)
{
png_uint_32 temp;
/* Length check; this cannot be ignored in this code because profile_length
* is used later to check the tag table, so even if the profile seems over
* long profile_length from the caller must be correct. The caller can fix
* this up on read or write by just passing in the profile header length.
*/
temp = png_get_uint_32(profile);
if (temp != profile_length)
return png_icc_profile_error(png_ptr, colorspace, name, temp,
"length does not match profile");
temp = (png_uint_32) (*(profile+8));
if (temp > 3 && (profile_length & 3))
return png_icc_profile_error(png_ptr, colorspace, name, profile_length,
"invalid length");
temp = png_get_uint_32(profile+128); /* tag count: 12 bytes/tag */
if (temp > 357913930 || /* (2^32-4-132)/12: maximum possible tag count */
profile_length < 132+12*temp) /* truncated tag table */
return png_icc_profile_error(png_ptr, colorspace, name, temp,
"tag count too large");
/* The 'intent' must be valid or we can't store it, ICC limits the intent to
* 16 bits.
*/
temp = png_get_uint_32(profile+64);
if (temp >= 0xffff) /* The ICC limit */
return png_icc_profile_error(png_ptr, colorspace, name, temp,
"invalid rendering intent");
/* This is just a warning because the profile may be valid in future
* versions.
*/
if (temp >= PNG_sRGB_INTENT_LAST)
(void)png_icc_profile_error(png_ptr, NULL, name, temp,
"intent outside defined range");
/* At this point the tag table can't be checked because it hasn't necessarily
* been loaded; however, various header fields can be checked. These checks
* are for values permitted by the PNG spec in an ICC profile; the PNG spec
* restricts the profiles that can be passed in an iCCP chunk (they must be
* appropriate to processing PNG data!)
*/
/* Data checks (could be skipped). These checks must be independent of the
* version number; however, the version number doesn't accommodate changes in
* the header fields (just the known tags and the interpretation of the
* data.)
*/
temp = png_get_uint_32(profile+36); /* signature 'ascp' */
if (temp != 0x61637370)
return png_icc_profile_error(png_ptr, colorspace, name, temp,
"invalid signature");
/* Currently the PCS illuminant/adopted white point (the computational
* white point) are required to be D50,
* however the profile contains a record of the illuminant so perhaps ICC
* expects to be able to change this in the future (despite the rationale in
* the introduction for using a fixed PCS adopted white.) Consequently the
* following is just a warning.
*/
if (memcmp(profile+68, D50_nCIEXYZ, 12) != 0)
(void)png_icc_profile_error(png_ptr, NULL, name, 0/*no tag value*/,
"PCS illuminant is not D50");
/* The PNG spec requires this:
* "If the iCCP chunk is present, the image samples conform to the colour
* space represented by the embedded ICC profile as defined by the
* International Color Consortium [ICC]. The colour space of the ICC profile
* shall be an RGB colour space for colour images (PNG colour types 2, 3, and
* 6), or a greyscale colour space for greyscale images (PNG colour types 0
* and 4)."
*
* This checking code ensures the embedded profile (on either read or write)
* conforms to the specification requirements. Notice that an ICC 'gray'
* color-space profile contains the information to transform the monochrome
* data to XYZ or L*a*b (according to which PCS the profile uses) and this
* should be used in preference to the standard libpng K channel replication
* into R, G and B channels.
*
* Previously it was suggested that an RGB profile on grayscale data could be
* handled. However it it is clear that using an RGB profile in this context
* must be an error - there is no specification of what it means. Thus it is
* almost certainly more correct to ignore the profile.
*/
temp = png_get_uint_32(profile+16); /* data colour space field */
switch (temp)
{
case 0x52474220: /* 'RGB ' */
if ((color_type & PNG_COLOR_MASK_COLOR) == 0)
return png_icc_profile_error(png_ptr, colorspace, name, temp,
"RGB color space not permitted on grayscale PNG");
break;
case 0x47524159: /* 'GRAY' */
if ((color_type & PNG_COLOR_MASK_COLOR) != 0)
return png_icc_profile_error(png_ptr, colorspace, name, temp,
"Gray color space not permitted on RGB PNG");
break;
default:
return png_icc_profile_error(png_ptr, colorspace, name, temp,
"invalid ICC profile color space");
}
/* It is up to the application to check that the profile class matches the
* application requirements; the spec provides no guidance, but it's pretty
* weird if the profile is not scanner ('scnr'), monitor ('mntr'), printer
* ('prtr') or 'spac' (for generic color spaces). Issue a warning in these
* cases. Issue an error for device link or abstract profiles - these don't
* contain the records necessary to transform the color-space to anything
* other than the target device (and not even that for an abstract profile).
* Profiles of these classes may not be embedded in images.
*/
temp = png_get_uint_32(profile+12); /* profile/device class */
switch (temp)
{
case 0x73636e72: /* 'scnr' */
case 0x6d6e7472: /* 'mntr' */
case 0x70727472: /* 'prtr' */
case 0x73706163: /* 'spac' */
/* All supported */
break;
case 0x61627374: /* 'abst' */
/* May not be embedded in an image */
return png_icc_profile_error(png_ptr, colorspace, name, temp,
"invalid embedded Abstract ICC profile");
case 0x6c696e6b: /* 'link' */
/* DeviceLink profiles cannot be interpreted in a non-device specific
* fashion, if an app uses the AToB0Tag in the profile the results are
* undefined unless the result is sent to the intended device,
* therefore a DeviceLink profile should not be found embedded in a
* PNG.
*/
return png_icc_profile_error(png_ptr, colorspace, name, temp,
"unexpected DeviceLink ICC profile class");
case 0x6e6d636c: /* 'nmcl' */
/* A NamedColor profile is also device specific, however it doesn't
* contain an AToB0 tag that is open to misinterpretation. Almost
* certainly it will fail the tests below.
*/
(void)png_icc_profile_error(png_ptr, NULL, name, temp,
"unexpected NamedColor ICC profile class");
break;
default:
/* To allow for future enhancements to the profile accept unrecognized
* profile classes with a warning, these then hit the test below on the
* tag content to ensure they are backward compatible with one of the
* understood profiles.
*/
(void)png_icc_profile_error(png_ptr, NULL, name, temp,
"unrecognized ICC profile class");
break;
}
/* For any profile other than a device link one the PCS must be encoded
* either in XYZ or Lab.
*/
temp = png_get_uint_32(profile+20);
switch (temp)
{
case 0x58595a20: /* 'XYZ ' */
case 0x4c616220: /* 'Lab ' */
break;
default:
return png_icc_profile_error(png_ptr, colorspace, name, temp,
"unexpected ICC PCS encoding");
}
return 1;
}
int /* PRIVATE */
png_icc_check_tag_table(png_const_structrp png_ptr, png_colorspacerp colorspace,
png_const_charp name, png_uint_32 profile_length,
png_const_bytep profile /* header plus whole tag table */)
{
png_uint_32 tag_count = png_get_uint_32(profile+128);
png_uint_32 itag;
png_const_bytep tag = profile+132; /* The first tag */
/* First scan all the tags in the table and add bits to the icc_info value
* (temporarily in 'tags').
*/
for (itag=0; itag < tag_count; ++itag, tag += 12)
{
png_uint_32 tag_id = png_get_uint_32(tag+0);
png_uint_32 tag_start = png_get_uint_32(tag+4); /* must be aligned */
png_uint_32 tag_length = png_get_uint_32(tag+8);/* not padded */
/* The ICC specification does not exclude zero length tags, therefore the
* start might actually be anywhere if there is no data, but this would be
* a clear abuse of the intent of the standard so the start is checked for
* being in range. All defined tag types have an 8 byte header - a 4 byte
* type signature then 0.
*/
/* This is a hard error; potentially it can cause read outside the
* profile.
*/
if (tag_start > profile_length || tag_length > profile_length - tag_start)
return png_icc_profile_error(png_ptr, colorspace, name, tag_id,
"ICC profile tag outside profile");
if ((tag_start & 3) != 0)
{
/* CNHP730S.icc shipped with Microsoft Windows 64 violates this; it is
* only a warning here because libpng does not care about the
* alignment.
*/
(void)png_icc_profile_error(png_ptr, NULL, name, tag_id,
"ICC profile tag start not a multiple of 4");
}
}
return 1; /* success, maybe with warnings */
}
#ifdef PNG_sRGB_SUPPORTED
#if PNG_sRGB_PROFILE_CHECKS >= 0
/* Information about the known ICC sRGB profiles */
static const struct
{
png_uint_32 adler, crc, length;
png_uint_32 md5[4];
png_byte have_md5;
png_byte is_broken;
png_uint_16 intent;
# define PNG_MD5(a,b,c,d) { a, b, c, d }, (a!=0)||(b!=0)||(c!=0)||(d!=0)
# define PNG_ICC_CHECKSUM(adler, crc, md5, intent, broke, date, length, fname)\
{ adler, crc, length, md5, broke, intent },
} png_sRGB_checks[] =
{
/* This data comes from contrib/tools/checksum-icc run on downloads of
* all four ICC sRGB profiles from www.color.org.
*/
/* adler32, crc32, MD5[4], intent, date, length, file-name */
PNG_ICC_CHECKSUM(0x0a3fd9f6, 0x3b8772b9,
PNG_MD5(0x29f83dde, 0xaff255ae, 0x7842fae4, 0xca83390d), 0, 0,
"2009/03/27 21:36:31", 3048, "sRGB_IEC61966-2-1_black_scaled.icc")
/* ICC sRGB v2 perceptual no black-compensation: */
PNG_ICC_CHECKSUM(0x4909e5e1, 0x427ebb21,
PNG_MD5(0xc95bd637, 0xe95d8a3b, 0x0df38f99, 0xc1320389), 1, 0,
"2009/03/27 21:37:45", 3052, "sRGB_IEC61966-2-1_no_black_scaling.icc")
PNG_ICC_CHECKSUM(0xfd2144a1, 0x306fd8ae,
PNG_MD5(0xfc663378, 0x37e2886b, 0xfd72e983, 0x8228f1b8), 0, 0,
"2009/08/10 17:28:01", 60988, "sRGB_v4_ICC_preference_displayclass.icc")
/* ICC sRGB v4 perceptual */
PNG_ICC_CHECKSUM(0x209c35d2, 0xbbef7812,
PNG_MD5(0x34562abf, 0x994ccd06, 0x6d2c5721, 0xd0d68c5d), 0, 0,
"2007/07/25 00:05:37", 60960, "sRGB_v4_ICC_preference.icc")
/* The following profiles have no known MD5 checksum. If there is a match
* on the (empty) MD5 the other fields are used to attempt a match and
* a warning is produced. The first two of these profiles have a 'cprt' tag
* which suggests that they were also made by Hewlett Packard.
*/
PNG_ICC_CHECKSUM(0xa054d762, 0x5d5129ce,
PNG_MD5(0x00000000, 0x00000000, 0x00000000, 0x00000000), 1, 0,
"2004/07/21 18:57:42", 3024, "sRGB_IEC61966-2-1_noBPC.icc")
/* This is a 'mntr' (display) profile with a mediaWhitePointTag that does not
* match the D50 PCS illuminant in the header (it is in fact the D65 values,
* so the white point is recorded as the un-adapted value.) The profiles
* below only differ in one byte - the intent - and are basically the same as
* the previous profile except for the mediaWhitePointTag error and a missing
* chromaticAdaptationTag.
*/
PNG_ICC_CHECKSUM(0xf784f3fb, 0x182ea552,
PNG_MD5(0x00000000, 0x00000000, 0x00000000, 0x00000000), 0, 1/*broken*/,
"1998/02/09 06:49:00", 3144, "HP-Microsoft sRGB v2 perceptual")
PNG_ICC_CHECKSUM(0x0398f3fc, 0xf29e526d,
PNG_MD5(0x00000000, 0x00000000, 0x00000000, 0x00000000), 1, 1/*broken*/,
"1998/02/09 06:49:00", 3144, "HP-Microsoft sRGB v2 media-relative")
};
static int
png_compare_ICC_profile_with_sRGB(png_const_structrp png_ptr,
png_const_bytep profile, uLong adler)
{
/* The quick check is to verify just the MD5 signature and trust the
* rest of the data. Because the profile has already been verified for
* correctness this is safe. png_colorspace_set_sRGB will check the 'intent'
* field too, so if the profile has been edited with an intent not defined
* by sRGB (but maybe defined by a later ICC specification) the read of
* the profile will fail at that point.
*/
png_uint_32 length = 0;
png_uint_32 intent = 0x10000; /* invalid */
#if PNG_sRGB_PROFILE_CHECKS > 1
uLong crc = 0; /* the value for 0 length data */
#endif
unsigned int i;
#ifdef PNG_SET_OPTION_SUPPORTED
/* First see if PNG_SKIP_sRGB_CHECK_PROFILE has been set to "on" */
if (((png_ptr->options >> PNG_SKIP_sRGB_CHECK_PROFILE) & 3) ==
PNG_OPTION_ON)
return 0;
#endif
for (i=0; i < (sizeof png_sRGB_checks) / (sizeof png_sRGB_checks[0]); ++i)
{
if (png_get_uint_32(profile+84) == png_sRGB_checks[i].md5[0] &&
png_get_uint_32(profile+88) == png_sRGB_checks[i].md5[1] &&
png_get_uint_32(profile+92) == png_sRGB_checks[i].md5[2] &&
png_get_uint_32(profile+96) == png_sRGB_checks[i].md5[3])
{
/* This may be one of the old HP profiles without an MD5, in that
* case we can only use the length and Adler32 (note that these
* are not used by default if there is an MD5!)
*/
# if PNG_sRGB_PROFILE_CHECKS == 0
if (png_sRGB_checks[i].have_md5 != 0)
return 1+png_sRGB_checks[i].is_broken;
# endif
/* Profile is unsigned or more checks have been configured in. */
if (length == 0)
{
length = png_get_uint_32(profile);
intent = png_get_uint_32(profile+64);
}
/* Length *and* intent must match */
if (length == (png_uint_32) png_sRGB_checks[i].length &&
intent == (png_uint_32) png_sRGB_checks[i].intent)
{
/* Now calculate the adler32 if not done already. */
if (adler == 0)
{
adler = adler32(0, NULL, 0);
adler = adler32(adler, profile, length);
}
if (adler == png_sRGB_checks[i].adler)
{
/* These basic checks suggest that the data has not been
* modified, but if the check level is more than 1 perform
* our own crc32 checksum on the data.
*/
# if PNG_sRGB_PROFILE_CHECKS > 1
if (crc == 0)
{
crc = crc32(0, NULL, 0);
crc = crc32(crc, profile, length);
}
/* So this check must pass for the 'return' below to happen.
*/
if (crc == png_sRGB_checks[i].crc)
# endif
{
if (png_sRGB_checks[i].is_broken != 0)
{
/* These profiles are known to have bad data that may cause
* problems if they are used, therefore attempt to
* discourage their use, skip the 'have_md5' warning below,
* which is made irrelevant by this error.
*/
png_chunk_report(png_ptr, "known incorrect sRGB profile",
PNG_CHUNK_ERROR);
}
/* Warn that this being done; this isn't even an error since
* the profile is perfectly valid, but it would be nice if
* people used the up-to-date ones.
*/
else if (png_sRGB_checks[i].have_md5 == 0)
{
png_chunk_report(png_ptr,
"out-of-date sRGB profile with no signature",
PNG_CHUNK_WARNING);
}
return 1+png_sRGB_checks[i].is_broken;
}
}
# if PNG_sRGB_PROFILE_CHECKS > 0
/* The signature matched, but the profile had been changed in some
* way. This probably indicates a data error or uninformed hacking.
* Fall through to "no match".
*/
png_chunk_report(png_ptr,
"Not recognizing known sRGB profile that has been edited",
PNG_CHUNK_WARNING);
break;
# endif
}
}
}
return 0; /* no match */
}
void /* PRIVATE */
png_icc_set_sRGB(png_const_structrp png_ptr,
png_colorspacerp colorspace, png_const_bytep profile, uLong adler)
{
/* Is this profile one of the known ICC sRGB profiles? If it is, just set
* the sRGB information.
*/
if (png_compare_ICC_profile_with_sRGB(png_ptr, profile, adler) != 0)
(void)png_colorspace_set_sRGB(png_ptr, colorspace,
(int)/*already checked*/png_get_uint_32(profile+64));
}
#endif /* PNG_sRGB_PROFILE_CHECKS >= 0 */
#endif /* sRGB */
int /* PRIVATE */
png_colorspace_set_ICC(png_const_structrp png_ptr, png_colorspacerp colorspace,
png_const_charp name, png_uint_32 profile_length, png_const_bytep profile,
int color_type)
{
if ((colorspace->flags & PNG_COLORSPACE_INVALID) != 0)
return 0;
if (icc_check_length(png_ptr, colorspace, name, profile_length) != 0 &&
png_icc_check_header(png_ptr, colorspace, name, profile_length, profile,
color_type) != 0 &&
png_icc_check_tag_table(png_ptr, colorspace, name, profile_length,
profile) != 0)
{
# if defined(PNG_sRGB_SUPPORTED) && PNG_sRGB_PROFILE_CHECKS >= 0
/* If no sRGB support, don't try storing sRGB information */
png_icc_set_sRGB(png_ptr, colorspace, profile, 0);
# endif
return 1;
}
/* Failure case */
return 0;
}
#endif /* iCCP */
#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
void /* PRIVATE */
png_colorspace_set_rgb_coefficients(png_structrp png_ptr)
{
/* Set the rgb_to_gray coefficients from the colorspace. */
if (png_ptr->rgb_to_gray_coefficients_set == 0 &&
(png_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_ENDPOINTS) != 0)
{
/* png_set_background has not been called, get the coefficients from the Y
* values of the colorspace colorants.
*/
png_fixed_point r = png_ptr->colorspace.end_points_XYZ.red_Y;
png_fixed_point g = png_ptr->colorspace.end_points_XYZ.green_Y;
png_fixed_point b = png_ptr->colorspace.end_points_XYZ.blue_Y;
png_fixed_point total = r+g+b;
if (total > 0 &&
r >= 0 && png_muldiv(&r, r, 32768, total) && r >= 0 && r <= 32768 &&
g >= 0 && png_muldiv(&g, g, 32768, total) && g >= 0 && g <= 32768 &&
b >= 0 && png_muldiv(&b, b, 32768, total) && b >= 0 && b <= 32768 &&
r+g+b <= 32769)
{
/* We allow 0 coefficients here. r+g+b may be 32769 if two or
* all of the coefficients were rounded up. Handle this by
* reducing the *largest* coefficient by 1; this matches the
* approach used for the default coefficients in pngrtran.c
*/
int add = 0;
if (r+g+b > 32768)
add = -1;
else if (r+g+b < 32768)
add = 1;
if (add != 0)
{
if (g >= r && g >= b)
g += add;
else if (r >= g && r >= b)
r += add;
else
b += add;
}
/* Check for an internal error. */
if (r+g+b != 32768)
png_error(png_ptr,
"internal error handling cHRM coefficients");
else
{
png_ptr->rgb_to_gray_red_coeff = (png_uint_16)r;
png_ptr->rgb_to_gray_green_coeff = (png_uint_16)g;
}
}
/* This is a png_error at present even though it could be ignored -
* it should never happen, but it is important that if it does, the
* bug is fixed.
*/
else
png_error(png_ptr, "internal error handling cHRM->XYZ");
}
}
#endif /* READ_RGB_TO_GRAY */
#endif /* COLORSPACE */
#ifdef __GNUC__
/* This exists solely to work round a warning from GNU C. */
static int /* PRIVATE */
png_gt(size_t a, size_t b)
{
return a > b;
}
#else
# define png_gt(a,b) ((a) > (b))
#endif
void /* PRIVATE */
png_check_IHDR(png_const_structrp png_ptr,
png_uint_32 width, png_uint_32 height, int bit_depth,
int color_type, int interlace_type, int compression_type,
int filter_type)
{
int error = 0;
/* Check for width and height valid values */
if (width == 0)
{
png_warning(png_ptr, "Image width is zero in IHDR");
error = 1;
}
if (width > PNG_UINT_31_MAX)
{
png_warning(png_ptr, "Invalid image width in IHDR");
error = 1;
}
if (png_gt(((width + 7) & (~7U)),
((PNG_SIZE_MAX
- 48 /* big_row_buf hack */
- 1) /* filter byte */
/ 8) /* 8-byte RGBA pixels */
- 1)) /* extra max_pixel_depth pad */
{
/* The size of the row must be within the limits of this architecture.
* Because the read code can perform arbitrary transformations the
* maximum size is checked here. Because the code in png_read_start_row
* adds extra space "for safety's sake" in several places a conservative
* limit is used here.
*
* NOTE: it would be far better to check the size that is actually used,
* but the effect in the real world is minor and the changes are more
* extensive, therefore much more dangerous and much more difficult to
* write in a way that avoids compiler warnings.
*/
png_warning(png_ptr, "Image width is too large for this architecture");
error = 1;
}
#ifdef PNG_SET_USER_LIMITS_SUPPORTED
if (width > png_ptr->user_width_max)
#else
if (width > PNG_USER_WIDTH_MAX)
#endif
{
png_warning(png_ptr, "Image width exceeds user limit in IHDR");
error = 1;
}
if (height == 0)
{
png_warning(png_ptr, "Image height is zero in IHDR");
error = 1;
}
if (height > PNG_UINT_31_MAX)
{
png_warning(png_ptr, "Invalid image height in IHDR");
error = 1;
}
#ifdef PNG_SET_USER_LIMITS_SUPPORTED
if (height > png_ptr->user_height_max)
#else
if (height > PNG_USER_HEIGHT_MAX)
#endif
{
png_warning(png_ptr, "Image height exceeds user limit in IHDR");
error = 1;
}
/* Check other values */
if (bit_depth != 1 && bit_depth != 2 && bit_depth != 4 &&
bit_depth != 8 && bit_depth != 16)
{
png_warning(png_ptr, "Invalid bit depth in IHDR");
error = 1;
}
if (color_type < 0 || color_type == 1 ||
color_type == 5 || color_type > 6)
{
png_warning(png_ptr, "Invalid color type in IHDR");
error = 1;
}
if (((color_type == PNG_COLOR_TYPE_PALETTE) && bit_depth > 8) ||
((color_type == PNG_COLOR_TYPE_RGB ||
color_type == PNG_COLOR_TYPE_GRAY_ALPHA ||
color_type == PNG_COLOR_TYPE_RGB_ALPHA) && bit_depth < 8))
{
png_warning(png_ptr, "Invalid color type/bit depth combination in IHDR");
error = 1;
}
if (interlace_type >= PNG_INTERLACE_LAST)
{
png_warning(png_ptr, "Unknown interlace method in IHDR");
error = 1;
}
if (compression_type != PNG_COMPRESSION_TYPE_BASE)
{
png_warning(png_ptr, "Unknown compression method in IHDR");
error = 1;
}
#ifdef PNG_MNG_FEATURES_SUPPORTED
/* Accept filter_method 64 (intrapixel differencing) only if
* 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and
* 2. Libpng did not read a PNG signature (this filter_method is only
* used in PNG datastreams that are embedded in MNG datastreams) and
* 3. The application called png_permit_mng_features with a mask that
* included PNG_FLAG_MNG_FILTER_64 and
* 4. The filter_method is 64 and
* 5. The color_type is RGB or RGBA
*/
if ((png_ptr->mode & PNG_HAVE_PNG_SIGNATURE) != 0 &&
png_ptr->mng_features_permitted != 0)
png_warning(png_ptr, "MNG features are not allowed in a PNG datastream");
if (filter_type != PNG_FILTER_TYPE_BASE)
{
if (!((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) != 0 &&
(filter_type == PNG_INTRAPIXEL_DIFFERENCING) &&
((png_ptr->mode & PNG_HAVE_PNG_SIGNATURE) == 0) &&
(color_type == PNG_COLOR_TYPE_RGB ||
color_type == PNG_COLOR_TYPE_RGB_ALPHA)))
{
png_warning(png_ptr, "Unknown filter method in IHDR");
error = 1;
}
if ((png_ptr->mode & PNG_HAVE_PNG_SIGNATURE) != 0)
{
png_warning(png_ptr, "Invalid filter method in IHDR");
error = 1;
}
}
#else
if (filter_type != PNG_FILTER_TYPE_BASE)
{
png_warning(png_ptr, "Unknown filter method in IHDR");
error = 1;
}
#endif
if (error == 1)
png_error(png_ptr, "Invalid IHDR data");
}
#if defined(PNG_sCAL_SUPPORTED) || defined(PNG_pCAL_SUPPORTED)
/* ASCII to fp functions */
/* Check an ASCII formatted floating point value, see the more detailed
* comments in pngpriv.h
*/
/* The following is used internally to preserve the sticky flags */
#define png_fp_add(state, flags) ((state) |= (flags))
#define png_fp_set(state, value) ((state) = (value) | ((state) & PNG_FP_STICKY))
int /* PRIVATE */
png_check_fp_number(png_const_charp string, size_t size, int *statep,
png_size_tp whereami)
{
int state = *statep;
size_t i = *whereami;
while (i < size)
{
int type;
/* First find the type of the next character */
switch (string[i])
{
case 43: type = PNG_FP_SAW_SIGN; break;
case 45: type = PNG_FP_SAW_SIGN + PNG_FP_NEGATIVE; break;
case 46: type = PNG_FP_SAW_DOT; break;
case 48: type = PNG_FP_SAW_DIGIT; break;
case 49: case 50: case 51: case 52:
case 53: case 54: case 55: case 56:
case 57: type = PNG_FP_SAW_DIGIT + PNG_FP_NONZERO; break;
case 69:
case 101: type = PNG_FP_SAW_E; break;
default: goto PNG_FP_End;
}
/* Now deal with this type according to the current
* state, the type is arranged to not overlap the
* bits of the PNG_FP_STATE.
*/
switch ((state & PNG_FP_STATE) + (type & PNG_FP_SAW_ANY))
{
case PNG_FP_INTEGER + PNG_FP_SAW_SIGN:
if ((state & PNG_FP_SAW_ANY) != 0)
goto PNG_FP_End; /* not a part of the number */
png_fp_add(state, type);
break;
case PNG_FP_INTEGER + PNG_FP_SAW_DOT:
/* Ok as trailer, ok as lead of fraction. */
if ((state & PNG_FP_SAW_DOT) != 0) /* two dots */
goto PNG_FP_End;
else if ((state & PNG_FP_SAW_DIGIT) != 0) /* trailing dot? */
png_fp_add(state, type);
else
png_fp_set(state, PNG_FP_FRACTION | type);
break;
case PNG_FP_INTEGER + PNG_FP_SAW_DIGIT:
if ((state & PNG_FP_SAW_DOT) != 0) /* delayed fraction */
png_fp_set(state, PNG_FP_FRACTION | PNG_FP_SAW_DOT);
png_fp_add(state, type | PNG_FP_WAS_VALID);
break;
case PNG_FP_INTEGER + PNG_FP_SAW_E:
if ((state & PNG_FP_SAW_DIGIT) == 0)
goto PNG_FP_End;
png_fp_set(state, PNG_FP_EXPONENT);
break;
/* case PNG_FP_FRACTION + PNG_FP_SAW_SIGN:
goto PNG_FP_End; ** no sign in fraction */
/* case PNG_FP_FRACTION + PNG_FP_SAW_DOT:
goto PNG_FP_End; ** Because SAW_DOT is always set */
case PNG_FP_FRACTION + PNG_FP_SAW_DIGIT:
png_fp_add(state, type | PNG_FP_WAS_VALID);
break;
case PNG_FP_FRACTION + PNG_FP_SAW_E:
/* This is correct because the trailing '.' on an
* integer is handled above - so we can only get here
* with the sequence ".E" (with no preceding digits).
*/
if ((state & PNG_FP_SAW_DIGIT) == 0)
goto PNG_FP_End;
png_fp_set(state, PNG_FP_EXPONENT);
break;
case PNG_FP_EXPONENT + PNG_FP_SAW_SIGN:
if ((state & PNG_FP_SAW_ANY) != 0)
goto PNG_FP_End; /* not a part of the number */
png_fp_add(state, PNG_FP_SAW_SIGN);
break;
/* case PNG_FP_EXPONENT + PNG_FP_SAW_DOT:
goto PNG_FP_End; */
case PNG_FP_EXPONENT + PNG_FP_SAW_DIGIT:
png_fp_add(state, PNG_FP_SAW_DIGIT | PNG_FP_WAS_VALID);
break;
/* case PNG_FP_EXPONEXT + PNG_FP_SAW_E:
goto PNG_FP_End; */
default: goto PNG_FP_End; /* I.e. break 2 */
}
/* The character seems ok, continue. */
++i;
}
PNG_FP_End:
/* Here at the end, update the state and return the correct
* return code.
*/
*statep = state;
*whereami = i;
return (state & PNG_FP_SAW_DIGIT) != 0;
}
/* The same but for a complete string. */
int
png_check_fp_string(png_const_charp string, size_t size)
{
int state=0;
size_t char_index=0;
if (png_check_fp_number(string, size, &state, &char_index) != 0 &&
(char_index == size || string[char_index] == 0))
return state /* must be non-zero - see above */;
return 0; /* i.e. fail */
}
#endif /* pCAL || sCAL */
#ifdef PNG_sCAL_SUPPORTED
# ifdef PNG_FLOATING_POINT_SUPPORTED
/* Utility used below - a simple accurate power of ten from an integral
* exponent.
*/
static double
png_pow10(int power)
{
int recip = 0;
double d = 1;
/* Handle negative exponent with a reciprocal at the end because
* 10 is exact whereas .1 is inexact in base 2
*/
if (power < 0)
{
if (power < DBL_MIN_10_EXP) return 0;
recip = 1; power = -power;
}
if (power > 0)
{
/* Decompose power bitwise. */
double mult = 10;
do
{
if (power & 1) d *= mult;
mult *= mult;
power >>= 1;
}
while (power > 0);
if (recip != 0) d = 1/d;
}
/* else power is 0 and d is 1 */
return d;
}
/* Function to format a floating point value in ASCII with a given
* precision.
*/
#if GCC_STRICT_OVERFLOW
#pragma GCC diagnostic push
/* The problem arises below with exp_b10, which can never overflow because it
* comes, originally, from frexp and is therefore limited to a range which is
* typically +/-710 (log2(DBL_MAX)/log2(DBL_MIN)).
*/
#pragma GCC diagnostic warning "-Wstrict-overflow=2"
#endif /* GCC_STRICT_OVERFLOW */
void /* PRIVATE */
png_ascii_from_fp(png_const_structrp png_ptr, png_charp ascii, size_t size,
double fp, unsigned int precision)
{
/* We use standard functions from math.h, but not printf because
* that would require stdio. The caller must supply a buffer of
* sufficient size or we will png_error. The tests on size and
* the space in ascii[] consumed are indicated below.
*/
if (precision < 1)
precision = DBL_DIG;
/* Enforce the limit of the implementation precision too. */
if (precision > DBL_DIG+1)
precision = DBL_DIG+1;
/* Basic sanity checks */
if (size >= precision+5) /* See the requirements below. */
{
if (fp < 0)
{
fp = -fp;
*ascii++ = 45; /* '-' PLUS 1 TOTAL 1 */
--size;
}
if (fp >= DBL_MIN && fp <= DBL_MAX)
{
int exp_b10; /* A base 10 exponent */
double base; /* 10^exp_b10 */
/* First extract a base 10 exponent of the number,
* the calculation below rounds down when converting
* from base 2 to base 10 (multiply by log10(2) -
* 0.3010, but 77/256 is 0.3008, so exp_b10 needs to
* be increased. Note that the arithmetic shift
* performs a floor() unlike C arithmetic - using a
* C multiply would break the following for negative
* exponents.
*/
(void)frexp(fp, &exp_b10); /* exponent to base 2 */
exp_b10 = (exp_b10 * 77) >> 8; /* <= exponent to base 10 */
/* Avoid underflow here. */
base = png_pow10(exp_b10); /* May underflow */
while (base < DBL_MIN || base < fp)
{
/* And this may overflow. */
double test = png_pow10(exp_b10+1);
if (test <= DBL_MAX)
{
++exp_b10; base = test;
}
else
break;
}
/* Normalize fp and correct exp_b10, after this fp is in the
* range [.1,1) and exp_b10 is both the exponent and the digit
* *before* which the decimal point should be inserted
* (starting with 0 for the first digit). Note that this
* works even if 10^exp_b10 is out of range because of the
* test on DBL_MAX above.
*/
fp /= base;
while (fp >= 1)
{
fp /= 10; ++exp_b10;
}
/* Because of the code above fp may, at this point, be
* less than .1, this is ok because the code below can
* handle the leading zeros this generates, so no attempt
* is made to correct that here.
*/
{
unsigned int czero, clead, cdigits;
char exponent[10];
/* Allow up to two leading zeros - this will not lengthen
* the number compared to using E-n.
*/
if (exp_b10 < 0 && exp_b10 > -3) /* PLUS 3 TOTAL 4 */
{
czero = 0U-exp_b10; /* PLUS 2 digits: TOTAL 3 */
exp_b10 = 0; /* Dot added below before first output. */
}
else
czero = 0; /* No zeros to add */
/* Generate the digit list, stripping trailing zeros and
* inserting a '.' before a digit if the exponent is 0.
*/
clead = czero; /* Count of leading zeros */
cdigits = 0; /* Count of digits in list. */
do
{
double d;
fp *= 10;
/* Use modf here, not floor and subtract, so that
* the separation is done in one step. At the end
* of the loop don't break the number into parts so
* that the final digit is rounded.
*/
if (cdigits+czero+1 < precision+clead)
fp = modf(fp, &d);
else
{
d = floor(fp + .5);
if (d > 9)
{
/* Rounding up to 10, handle that here. */
if (czero > 0)
{
--czero; d = 1;
if (cdigits == 0) --clead;
}
else
{
while (cdigits > 0 && d > 9)
{
int ch = *--ascii;
if (exp_b10 != (-1))
++exp_b10;
else if (ch == 46)
{
ch = *--ascii; ++size;
/* Advance exp_b10 to '1', so that the
* decimal point happens after the
* previous digit.
*/
exp_b10 = 1;
}
--cdigits;
d = ch - 47; /* I.e. 1+(ch-48) */
}
/* Did we reach the beginning? If so adjust the
* exponent but take into account the leading
* decimal point.
*/
if (d > 9) /* cdigits == 0 */
{
if (exp_b10 == (-1))
{
/* Leading decimal point (plus zeros?), if
* we lose the decimal point here it must
* be reentered below.
*/
int ch = *--ascii;
if (ch == 46)
{
++size; exp_b10 = 1;
}
/* Else lost a leading zero, so 'exp_b10' is
* still ok at (-1)
*/
}
else
++exp_b10;
/* In all cases we output a '1' */
d = 1;
}
}
}
fp = 0; /* Guarantees termination below. */
}
if (d == 0)
{
++czero;
if (cdigits == 0) ++clead;
}
else
{
/* Included embedded zeros in the digit count. */
cdigits += czero - clead;
clead = 0;
while (czero > 0)
{
/* exp_b10 == (-1) means we just output the decimal
* place - after the DP don't adjust 'exp_b10' any
* more!
*/
if (exp_b10 != (-1))
{
if (exp_b10 == 0)
{
*ascii++ = 46; --size;
}
/* PLUS 1: TOTAL 4 */
--exp_b10;
}
*ascii++ = 48; --czero;
}
if (exp_b10 != (-1))
{
if (exp_b10 == 0)
{
*ascii++ = 46; --size; /* counted above */
}
--exp_b10;
}
*ascii++ = (char)(48 + (int)d); ++cdigits;
}
}
while (cdigits+czero < precision+clead && fp > DBL_MIN);
/* The total output count (max) is now 4+precision */
/* Check for an exponent, if we don't need one we are
* done and just need to terminate the string. At this
* point, exp_b10==(-1) is effectively a flag: it got
* to '-1' because of the decrement, after outputting
* the decimal point above. (The exponent required is
* *not* -1.)
*/
if (exp_b10 >= (-1) && exp_b10 <= 2)
{
/* The following only happens if we didn't output the
* leading zeros above for negative exponent, so this
* doesn't add to the digit requirement. Note that the
* two zeros here can only be output if the two leading
* zeros were *not* output, so this doesn't increase
* the output count.
*/
while (exp_b10-- > 0) *ascii++ = 48;
*ascii = 0;
/* Total buffer requirement (including the '\0') is
* 5+precision - see check at the start.
*/
return;
}
/* Here if an exponent is required, adjust size for
* the digits we output but did not count. The total
* digit output here so far is at most 1+precision - no
* decimal point and no leading or trailing zeros have
* been output.
*/
size -= cdigits;
*ascii++ = 69; --size; /* 'E': PLUS 1 TOTAL 2+precision */
/* The following use of an unsigned temporary avoids ambiguities in
* the signed arithmetic on exp_b10 and permits GCC at least to do
* better optimization.
*/
{
unsigned int uexp_b10;
if (exp_b10 < 0)
{
*ascii++ = 45; --size; /* '-': PLUS 1 TOTAL 3+precision */
uexp_b10 = 0U-exp_b10;
}
else
uexp_b10 = 0U+exp_b10;
cdigits = 0;
while (uexp_b10 > 0)
{
exponent[cdigits++] = (char)(48 + uexp_b10 % 10);
uexp_b10 /= 10;
}
}
/* Need another size check here for the exponent digits, so
* this need not be considered above.
*/
if (size > cdigits)
{
while (cdigits > 0) *ascii++ = exponent[--cdigits];
*ascii = 0;
return;
}
}
}
else if (!(fp >= DBL_MIN))
{
*ascii++ = 48; /* '0' */
*ascii = 0;
return;
}
else
{
*ascii++ = 105; /* 'i' */
*ascii++ = 110; /* 'n' */
*ascii++ = 102; /* 'f' */
*ascii = 0;
return;
}
}
/* Here on buffer too small. */
png_error(png_ptr, "ASCII conversion buffer too small");
}
#if GCC_STRICT_OVERFLOW
#pragma GCC diagnostic pop
#endif /* GCC_STRICT_OVERFLOW */
# endif /* FLOATING_POINT */
# ifdef PNG_FIXED_POINT_SUPPORTED
/* Function to format a fixed point value in ASCII.
*/
void /* PRIVATE */
png_ascii_from_fixed(png_const_structrp png_ptr, png_charp ascii,
size_t size, png_fixed_point fp)
{
/* Require space for 10 decimal digits, a decimal point, a minus sign and a
* trailing \0, 13 characters:
*/
if (size > 12)
{
png_uint_32 num;
/* Avoid overflow here on the minimum integer. */
if (fp < 0)
{
*ascii++ = 45; num = (png_uint_32)(-fp);
}
else
num = (png_uint_32)fp;
if (num <= 0x80000000) /* else overflowed */
{
unsigned int ndigits = 0, first = 16 /* flag value */;
char digits[10];
while (num)
{
/* Split the low digit off num: */
unsigned int tmp = num/10;
num -= tmp*10;
digits[ndigits++] = (char)(48 + num);
/* Record the first non-zero digit, note that this is a number
* starting at 1, it's not actually the array index.
*/
if (first == 16 && num > 0)
first = ndigits;
num = tmp;
}
if (ndigits > 0)
{
while (ndigits > 5) *ascii++ = digits[--ndigits];
/* The remaining digits are fractional digits, ndigits is '5' or
* smaller at this point. It is certainly not zero. Check for a
* non-zero fractional digit:
*/
if (first <= 5)
{
unsigned int i;
*ascii++ = 46; /* decimal point */
/* ndigits may be <5 for small numbers, output leading zeros
* then ndigits digits to first:
*/
i = 5;
while (ndigits < i)
{
*ascii++ = 48; --i;
}
while (ndigits >= first) *ascii++ = digits[--ndigits];
/* Don't output the trailing zeros! */
}
}
else
*ascii++ = 48;
/* And null terminate the string: */
*ascii = 0;
return;
}
}
/* Here on buffer too small. */
png_error(png_ptr, "ASCII conversion buffer too small");
}
# endif /* FIXED_POINT */
#endif /* SCAL */
#if defined(PNG_FLOATING_POINT_SUPPORTED) && \
!defined(PNG_FIXED_POINT_MACRO_SUPPORTED) && \
(defined(PNG_gAMA_SUPPORTED) || defined(PNG_cHRM_SUPPORTED) || \
defined(PNG_sCAL_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) || \
defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)) || \
(defined(PNG_sCAL_SUPPORTED) && \
defined(PNG_FLOATING_ARITHMETIC_SUPPORTED))
png_fixed_point
png_fixed(png_const_structrp png_ptr, double fp, png_const_charp text)
{
double r = floor(100000 * fp + .5);
if (r > 2147483647. || r < -2147483648.)
png_fixed_error(png_ptr, text);
# ifndef PNG_ERROR_TEXT_SUPPORTED
PNG_UNUSED(text)
# endif
return (png_fixed_point)r;
}
#endif
#if defined(PNG_GAMMA_SUPPORTED) || defined(PNG_COLORSPACE_SUPPORTED) ||\
defined(PNG_INCH_CONVERSIONS_SUPPORTED) || defined(PNG_READ_pHYs_SUPPORTED)
/* muldiv functions */
/* This API takes signed arguments and rounds the result to the nearest
* integer (or, for a fixed point number - the standard argument - to
* the nearest .00001). Overflow and divide by zero are signalled in
* the result, a boolean - true on success, false on overflow.
*/
#if GCC_STRICT_OVERFLOW /* from above */
/* It is not obvious which comparison below gets optimized in such a way that
* signed overflow would change the result; looking through the code does not
* reveal any tests which have the form GCC complains about, so presumably the
* optimizer is moving an add or subtract into the 'if' somewhere.
*/
#pragma GCC diagnostic push
#pragma GCC diagnostic warning "-Wstrict-overflow=2"
#endif /* GCC_STRICT_OVERFLOW */
int
png_muldiv(png_fixed_point_p res, png_fixed_point a, png_int_32 times,
png_int_32 divisor)
{
/* Return a * times / divisor, rounded. */
if (divisor != 0)
{
if (a == 0 || times == 0)
{
*res = 0;
return 1;
}
else
{
#ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
double r = a;
r *= times;
r /= divisor;
r = floor(r+.5);
/* A png_fixed_point is a 32-bit integer. */
if (r <= 2147483647. && r >= -2147483648.)
{
*res = (png_fixed_point)r;
return 1;
}
#else
int negative = 0;
png_uint_32 A, T, D;
png_uint_32 s16, s32, s00;
if (a < 0)
negative = 1, A = -a;
else
A = a;
if (times < 0)
negative = !negative, T = -times;
else
T = times;
if (divisor < 0)
negative = !negative, D = -divisor;
else
D = divisor;
/* Following can't overflow because the arguments only
* have 31 bits each, however the result may be 32 bits.
*/
s16 = (A >> 16) * (T & 0xffff) +
(A & 0xffff) * (T >> 16);
/* Can't overflow because the a*times bit is only 30
* bits at most.
*/
s32 = (A >> 16) * (T >> 16) + (s16 >> 16);
s00 = (A & 0xffff) * (T & 0xffff);
s16 = (s16 & 0xffff) << 16;
s00 += s16;
if (s00 < s16)
++s32; /* carry */
if (s32 < D) /* else overflow */
{
/* s32.s00 is now the 64-bit product, do a standard
* division, we know that s32 < D, so the maximum
* required shift is 31.
*/
int bitshift = 32;
png_fixed_point result = 0; /* NOTE: signed */
while (--bitshift >= 0)
{
png_uint_32 d32, d00;
if (bitshift > 0)
d32 = D >> (32-bitshift), d00 = D << bitshift;
else
d32 = 0, d00 = D;
if (s32 > d32)
{
if (s00 < d00) --s32; /* carry */
s32 -= d32, s00 -= d00, result += 1<<bitshift;
}
else
if (s32 == d32 && s00 >= d00)
s32 = 0, s00 -= d00, result += 1<<bitshift;
}
/* Handle the rounding. */
if (s00 >= (D >> 1))
++result;
if (negative != 0)
result = -result;
/* Check for overflow. */
if ((negative != 0 && result <= 0) ||
(negative == 0 && result >= 0))
{
*res = result;
return 1;
}
}
#endif
}
}
return 0;
}
#if GCC_STRICT_OVERFLOW
#pragma GCC diagnostic pop
#endif /* GCC_STRICT_OVERFLOW */
#endif /* READ_GAMMA || INCH_CONVERSIONS */
#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_INCH_CONVERSIONS_SUPPORTED)
/* The following is for when the caller doesn't much care about the
* result.
*/
png_fixed_point
png_muldiv_warn(png_const_structrp png_ptr, png_fixed_point a, png_int_32 times,
png_int_32 divisor)
{
png_fixed_point result;
if (png_muldiv(&result, a, times, divisor) != 0)
return result;
png_warning(png_ptr, "fixed point overflow ignored");
return 0;
}
#endif
#ifdef PNG_GAMMA_SUPPORTED /* more fixed point functions for gamma */
/* Calculate a reciprocal, return 0 on div-by-zero or overflow. */
png_fixed_point
png_reciprocal(png_fixed_point a)
{
#ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
double r = floor(1E10/a+.5);
if (r <= 2147483647. && r >= -2147483648.)
return (png_fixed_point)r;
#else
png_fixed_point res;
if (png_muldiv(&res, 100000, 100000, a) != 0)
return res;
#endif
return 0; /* error/overflow */
}
/* This is the shared test on whether a gamma value is 'significant' - whether
* it is worth doing gamma correction.
*/
int /* PRIVATE */
png_gamma_significant(png_fixed_point g
gitextract_0ngj2ibb/ ├── .gitattributes ├── .gitignore ├── CMakeLists.txt ├── LICENSE ├── README.rst ├── build.sh ├── jni/ │ ├── Android.mk │ ├── Application.mk │ ├── arm/ │ │ ├── arm_init.c │ │ ├── filter_neon.S │ │ ├── filter_neon_intrinsics.c │ │ └── palette_neon_intrinsics.c │ ├── config.h │ ├── example.c │ ├── png.c │ ├── png.h │ ├── pngconf.h │ ├── pngdebug.h │ ├── pngerror.c │ ├── pngget.c │ ├── pnginfo.h │ ├── pnglibconf.h │ ├── pngmem.c │ ├── pngpread.c │ ├── pngpriv.h │ ├── pngread.c │ ├── pngrio.c │ ├── pngrtran.c │ ├── pngrutil.c │ ├── pngset.c │ ├── pngstruct.h │ ├── pngtest.c │ ├── pngtrans.c │ ├── pngwio.c │ ├── pngwrite.c │ ├── pngwtran.c │ └── pngwutil.c └── png-config.cmake.in
SYMBOL INDEX (649 symbols across 25 files) FILE: jni/arm/arm_init.c function png_init_filter_functions_neon (line 57) | void FILE: jni/arm/filter_neon_intrinsics.c function png_read_filter_row_up_neon (line 50) | void function png_read_filter_row_sub3_neon (line 71) | void function png_read_filter_row_sub4_neon (line 118) | void function png_read_filter_row_avg3_neon (line 150) | void function png_read_filter_row_avg4_neon (line 218) | void function uint8x8_t (line 260) | static uint8x8_t function png_read_filter_row_paeth3_neon (line 287) | void function png_read_filter_row_paeth4_neon (line 355) | void FILE: jni/arm/palette_neon_intrinsics.c function png_riffle_palette_neon (line 24) | void function png_do_expand_palette_rgba8_neon (line 61) | int function png_do_expand_palette_rgb8_neon (line 105) | int FILE: jni/example.c function check_if_png (line 248) | int check_if_png(char *file_name, FILE **fp) function hilevel (line 576) | hilevel function process_data (line 637) | int function write_png (line 739) | void write_png(char *file_name /* , ... other image information ... */) FILE: jni/png.c type png_libpng_version_1_6_37 (line 17) | typedef png_libpng_version_1_6_37 Your_png_h_is_not_version_1_6_37; function png_set_sig_bytes (line 46) | void PNGAPI function png_sig_cmp (line 73) | int PNGAPI function png_zfree (line 117) | void /* PRIVATE */ function png_reset_crc (line 126) | void /* PRIVATE */ function png_calculate_crc (line 138) | void /* PRIVATE */ function png_user_version_check (line 192) | int function PNG_UNUSED (line 289) | PNG_UNUSED(mem_ptr) function png_destroy_info_struct (line 385) | void PNGAPI function png_data_freer (line 451) | void PNGAPI function png_free_data (line 470) | void PNGAPI function png_voidp (line 685) | png_voidp PNGAPI function png_init_io (line 702) | void PNGAPI function png_save_int_32 (line 725) | void PNGAPI function png_convert_to_rfc1123_buffer (line 736) | int PNGAPI function png_const_charp (line 790) | png_const_charp PNGAPI function png_const_charp (line 810) | png_const_charp PNGAPI function png_const_charp (line 836) | png_const_charp PNGAPI function png_const_charp (line 843) | png_const_charp PNGAPI function png_const_charp (line 851) | png_const_charp PNGAPI function png_build_grayscale_palette (line 874) | void PNGAPI function png_handle_as_unknown (line 925) | int PNGAPI function png_chunk_unknown_handling (line 960) | int /* PRIVATE */ function png_reset_zstream (line 973) | int PNGAPI function png_uint_32 (line 985) | png_uint_32 PNGAPI function png_zstream_error (line 997) | void /* PRIVATE */ function png_colorspace_check_gamma (line 1069) | static int function png_colorspace_set_gamma (line 1113) | void /* PRIVATE */ function png_colorspace_sync_info (line 1168) | void /* PRIVATE */ function png_colorspace_sync (line 1214) | void /* PRIVATE */ function png_xy_from_XYZ (line 1232) | static int function png_XYZ_from_xy (line 1275) | static int function png_XYZ_normalize (line 1541) | static int function png_colorspace_endpoints_match (line 1591) | static int function png_colorspace_check_xy (line 1617) | static int function png_colorspace_check_XYZ (line 1643) | static int function png_colorspace_set_xy_and_XYZ (line 1671) | static int function png_colorspace_set_chromaticities (line 1719) | int /* PRIVATE */ function png_colorspace_set_endpoints (line 1756) | int /* PRIVATE */ function png_icc_tag_char (line 1785) | static char function png_icc_tag_name (line 1795) | static void function is_ICC_signature_char (line 1806) | static int function is_ICC_signature (line 1813) | static int function png_chunk_report (line 1856) | PNG_UNUSED(pos) function icc_check_length (line 1969) | static int /* bool */ function png_compare_ICC_profile_with_sRGB (line 2306) | static int function png_icc_set_sRGB (line 2427) | void /* PRIVATE */ function png_colorspace_set_ICC (line 2441) | int /* PRIVATE */ function png_colorspace_set_rgb_coefficients (line 2468) | void /* PRIVATE */ function png_gt (line 2537) | static int /* PRIVATE */ function png_check_fp_number (line 2711) | int /* PRIVATE */ function png_check_fp_string (line 2838) | int function png_pow10 (line 2857) | static double function png_ascii_from_fp (line 2902) | void /* PRIVATE */ function png_ascii_from_fixed (line 3232) | void /* PRIVATE */ function png_fixed_point (line 3315) | png_fixed_point function png_muldiv (line 3348) | int function png_fixed_point (line 3471) | png_fixed_point function png_fixed_point (line 3487) | png_fixed_point function png_gamma_significant (line 3508) | int /* PRIVATE */ function png_fixed_point (line 3519) | static png_fixed_point function png_fixed_point (line 3542) | png_fixed_point function png_int_32 (line 3638) | static png_int_32 function png_int_32 (line 3695) | static png_int_32 function png_uint_32 (line 3787) | static png_uint_32 function png_byte (line 3835) | static png_byte function png_uint_16 (line 3850) | static png_uint_16 function png_byte (line 3863) | png_byte function png_uint_16 (line 3911) | png_uint_16 function png_uint_16 (line 3946) | png_uint_16 /* PRIVATE */ function png_build_16bit_table (line 3971) | static void function png_build_16to8_table (line 4048) | static void function png_build_8bit_table (line 4116) | static void function png_destroy_gamma_table (line 4135) | void /* PRIVATE */ function png_build_gamma_table (line 4195) | void /* PRIVATE */ function png_set_option (line 4331) | int PNGAPI function png_image_free_function (line 4521) | static int function png_image_free (line 4581) | void PNGAPI function png_image_error (line 4596) | int /* PRIVATE */ FILE: jni/png.h type png_struct (line 439) | typedef struct png_struct_def png_struct; type png_struct (line 440) | typedef const png_struct * png_const_structp; type png_struct (line 441) | typedef png_struct * png_structp; type png_struct (line 442) | typedef png_struct * * png_structpp; type png_info (line 453) | typedef struct png_info_def png_info; type png_info (line 454) | typedef png_info * png_infop; type png_info (line 455) | typedef const png_info * png_const_infop; type png_info (line 456) | typedef png_info * * png_infopp; type png_struct (line 469) | typedef png_struct * PNG_RESTRICT type png_struct (line 470) | typedef const png_struct * PNG_RESTRICT type png_info (line 471) | typedef png_info * PNG_RESTRICT type png_info (line 472) | typedef const png_info * PNG_RESTRICT type png_color (line 478) | typedef struct png_color_struct type png_color (line 484) | typedef png_color * png_colorp; type png_color (line 485) | typedef const png_color * png_const_colorp; type png_color (line 486) | typedef png_color * * png_colorpp; type png_color_16 (line 488) | typedef struct png_color_16_struct type png_color_16 (line 496) | typedef png_color_16 * png_color_16p; type png_color_16 (line 497) | typedef const png_color_16 * png_const_color_16p; type png_color_16 (line 498) | typedef png_color_16 * * png_color_16pp; type png_color_8 (line 500) | typedef struct png_color_8_struct type png_color_8 (line 508) | typedef png_color_8 * png_color_8p; type png_color_8 (line 509) | typedef const png_color_8 * png_const_color_8p; type png_color_8 (line 510) | typedef png_color_8 * * png_color_8pp; type png_sPLT_entry (line 516) | typedef struct png_sPLT_entry_struct type png_sPLT_entry (line 524) | typedef png_sPLT_entry * png_sPLT_entryp; type png_sPLT_entry (line 525) | typedef const png_sPLT_entry * png_const_sPLT_entryp; type png_sPLT_entry (line 526) | typedef png_sPLT_entry * * png_sPLT_entrypp; type png_sPLT_t (line 533) | typedef struct png_sPLT_struct type png_sPLT_t (line 540) | typedef png_sPLT_t * png_sPLT_tp; type png_sPLT_t (line 541) | typedef const png_sPLT_t * png_const_sPLT_tp; type png_sPLT_t (line 542) | typedef png_sPLT_t * * png_sPLT_tpp; type png_text (line 562) | typedef struct png_text_struct type png_text (line 579) | typedef png_text * png_textp; type png_text (line 580) | typedef const png_text * png_const_textp; type png_text (line 581) | typedef png_text * * png_textpp; type png_time (line 600) | typedef struct png_time_struct type png_time (line 609) | typedef png_time * png_timep; type png_time (line 610) | typedef const png_time * png_const_timep; type png_time (line 611) | typedef png_time * * png_timepp; type png_unknown_chunk (line 622) | typedef struct png_unknown_chunk_t type png_unknown_chunk (line 638) | typedef png_unknown_chunk * png_unknown_chunkp; type png_unknown_chunk (line 639) | typedef const png_unknown_chunk * png_const_unknown_chunkp; type png_unknown_chunk (line 640) | typedef png_unknown_chunk * * png_unknown_chunkpp; type png_row_info (line 754) | typedef struct png_row_info_struct type png_row_info (line 764) | typedef png_row_info * png_row_infop; type png_row_info (line 765) | typedef png_row_info * * png_row_infopp; type PNG_CALLBACK (line 775) | typedef PNG_CALLBACK(void, *png_error_ptr, (png_structp, png_const_charp)); type PNG_CALLBACK (line 776) | typedef PNG_CALLBACK(void, *png_rw_ptr, (png_structp, png_bytep, size_t)); type PNG_CALLBACK (line 777) | typedef PNG_CALLBACK(void, *png_flush_ptr, (png_structp)); type PNG_CALLBACK (line 778) | typedef PNG_CALLBACK(void, *png_read_status_ptr, (png_structp, png_uint_32, type PNG_CALLBACK (line 780) | typedef PNG_CALLBACK(void, *png_write_status_ptr, (png_structp, png_uint... type PNG_CALLBACK (line 784) | typedef PNG_CALLBACK(void, *png_progressive_info_ptr, (png_structp, png_... type PNG_CALLBACK (line 785) | typedef PNG_CALLBACK(void, *png_progressive_end_ptr, (png_structp, png_i... type PNG_CALLBACK (line 797) | typedef PNG_CALLBACK(void, *png_progressive_row_ptr, (png_structp, png_b... type PNG_CALLBACK (line 803) | typedef PNG_CALLBACK(void, *png_user_transform_ptr, (png_structp, png_ro... type PNG_CALLBACK (line 808) | typedef PNG_CALLBACK(int, *png_user_chunk_ptr, (png_structp, type PNG_CALLBACK (line 867) | typedef PNG_CALLBACK(png_voidp, *png_malloc_ptr, (png_structp, type PNG_CALLBACK (line 869) | typedef PNG_CALLBACK(void, *png_free_ptr, (png_structp, png_voidp)); type png_control (line 2671) | struct png_control type png_image (line 2672) | typedef struct FILE: jni/pngconf.h type png_byte (line 481) | typedef unsigned char png_byte; type png_int_16 (line 487) | typedef int png_int_16; type png_int_16 (line 489) | typedef short png_int_16; type png_uint_16 (line 495) | typedef unsigned int png_uint_16; type png_uint_16 (line 497) | typedef unsigned short png_uint_16; type png_int_32 (line 503) | typedef int png_int_32; type png_int_32 (line 505) | typedef long int png_int_32; type png_uint_32 (line 511) | typedef unsigned int png_uint_32; type png_uint_32 (line 513) | typedef unsigned long int png_uint_32; type png_size_t (line 523) | typedef size_t png_size_t; type png_ptrdiff_t (line 524) | typedef ptrdiff_t png_ptrdiff_t; type png_uint_32 (line 555) | typedef png_uint_32 png_alloc_size_t; type png_alloc_size_t (line 557) | typedef size_t png_alloc_size_t; type png_int_32 (line 574) | typedef png_int_32 png_fixed_point; type png_byte (line 579) | typedef png_byte * png_bytep; type png_byte (line 580) | typedef const png_byte * png_const_bytep; type png_uint_32 (line 581) | typedef png_uint_32 * png_uint_32p; type png_uint_32 (line 582) | typedef const png_uint_32 * png_const_uint_32p; type png_int_32 (line 583) | typedef png_int_32 * png_int_32p; type png_int_32 (line 584) | typedef const png_int_32 * png_const_int_32p; type png_uint_16 (line 585) | typedef png_uint_16 * png_uint_16p; type png_uint_16 (line 586) | typedef const png_uint_16 * png_const_uint_16p; type png_int_16 (line 587) | typedef png_int_16 * png_int_16p; type png_int_16 (line 588) | typedef const png_int_16 * png_const_int_16p; type png_fixed_point (line 591) | typedef png_fixed_point * png_fixed_point_p; type png_fixed_point (line 592) | typedef const png_fixed_point * png_const_fixed_point_p; type FILE (line 597) | typedef FILE * png_FILE_p; type png_byte (line 606) | typedef png_byte * * png_bytepp; type png_uint_32 (line 607) | typedef png_uint_32 * * png_uint_32pp; type png_int_32 (line 608) | typedef png_int_32 * * png_int_32pp; type png_uint_16 (line 609) | typedef png_uint_16 * * png_uint_16pp; type png_int_16 (line 610) | typedef png_int_16 * * png_int_16pp; type png_fixed_point (line 613) | typedef png_fixed_point * * png_fixed_point_pp; FILE: jni/pngerror.c function png_safecat (line 111) | size_t function png_charp (line 132) | png_charp function png_warning (line 215) | void PNGAPI function png_warning_parameter (line 246) | void function png_warning_parameter_unsigned (line 254) | void function png_warning_parameter_signed (line 262) | void function png_formatted_warning (line 283) | void function png_benign_error (line 361) | void PNGAPI function png_app_warning (line 391) | void /* PRIVATE */ function png_app_error (line 404) | void /* PRIVATE */ function png_format_buffer (line 433) | static void /* PRIVATE */ function png_chunk_warning (line 496) | void PNGAPI function png_chunk_benign_error (line 513) | void PNGAPI function png_chunk_report (line 530) | void /* PRIVATE */ function png_free_jmpbuf (line 665) | void /* PRIVATE */ function png_default_warning (line 784) | static void /* PRIVATE */ function png_set_error_fn (line 834) | void PNGAPI function png_voidp (line 855) | png_voidp PNGAPI function png_set_strip_error_numbers (line 866) | void PNGAPI function png_safe_warning (line 920) | void /* PRIVATE */ PNGCBAPI function png_safe_execute (line 935) | int /* PRIVATE */ FILE: jni/pngget.c function png_uint_32 (line 19) | png_uint_32 PNGAPI function png_get_rowbytes (line 29) | size_t PNGAPI function png_bytepp (line 39) | png_bytepp PNGAPI function png_uint_32 (line 51) | png_uint_32 PNGAPI function png_uint_32 (line 60) | png_uint_32 PNGAPI function png_byte (line 69) | png_byte PNGAPI function png_byte (line 78) | png_byte PNGAPI function png_byte (line 87) | png_byte PNGAPI function png_byte (line 96) | png_byte PNGAPI function png_byte (line 105) | png_byte PNGAPI function png_uint_32 (line 114) | png_uint_32 PNGAPI function png_uint_32 (line 136) | png_uint_32 PNGAPI function png_uint_32 (line 158) | png_uint_32 PNGAPI function png_get_pixel_aspect_ratio (line 180) | float PNGAPI function png_fixed_point (line 204) | png_fixed_point PNGAPI function png_int_32 (line 235) | png_int_32 PNGAPI function png_int_32 (line 255) | png_int_32 PNGAPI function png_int_32 (line 275) | png_int_32 PNGAPI function png_int_32 (line 295) | png_int_32 PNGAPI function png_uint_32 (line 316) | static png_uint_32 function png_uint_32 (line 348) | png_uint_32 PNGAPI function png_uint_32 (line 354) | png_uint_32 PNGAPI function png_uint_32 (line 360) | png_uint_32 PNGAPI function png_fixed_point (line 367) | static png_fixed_point function png_fixed_point (line 378) | png_fixed_point PNGAPI function png_fixed_point (line 388) | png_fixed_point PNGAPI function png_get_x_offset_inches (line 398) | float PNGAPI function png_get_y_offset_inches (line 409) | float PNGAPI function png_uint_32 (line 420) | png_uint_32 PNGAPI function png_byte (line 466) | png_byte PNGAPI function png_const_bytep (line 476) | png_const_bytep PNGAPI function png_uint_32 (line 487) | png_uint_32 PNGAPI function png_uint_32 (line 511) | png_uint_32 PNGAPI function png_uint_32 (line 557) | png_uint_32 PNGAPI function png_uint_32 (line 603) | png_uint_32 PNGAPI function png_uint_32 (line 640) | png_uint_32 PNGAPI function png_uint_32 (line 677) | png_uint_32 PNGAPI function png_uint_32 (line 696) | png_uint_32 PNGAPI function png_uint_32 (line 717) | png_uint_32 PNGAPI function png_uint_32 (line 735) | png_uint_32 PNGAPI function png_get_sPLT (line 763) | int PNGAPI function png_uint_32 (line 778) | png_uint_32 PNGAPI function png_uint_32 (line 788) | png_uint_32 PNGAPI function png_uint_32 (line 807) | png_uint_32 PNGAPI function png_uint_32 (line 824) | png_uint_32 PNGAPI function png_uint_32 (line 869) | png_uint_32 PNGAPI function png_uint_32 (line 890) | png_uint_32 PNGAPI function png_uint_32 (line 920) | png_uint_32 PNGAPI function png_uint_32 (line 943) | png_uint_32 PNGAPI function png_uint_32 (line 959) | png_uint_32 PNGAPI function png_uint_32 (line 977) | png_uint_32 PNGAPI function png_uint_32 (line 1011) | png_uint_32 PNGAPI function png_uint_32 (line 1030) | png_uint_32 PNGAPI function png_get_text (line 1048) | int PNGAPI function png_uint_32 (line 1074) | png_uint_32 PNGAPI function png_uint_32 (line 1092) | png_uint_32 PNGAPI function png_get_unknown_chunks (line 1138) | int PNGAPI function png_byte (line 1153) | png_byte PNGAPI function png_voidp (line 1161) | png_voidp PNGAPI function png_uint_32 (line 1194) | png_uint_32 PNGAPI function png_uint_32 (line 1200) | png_uint_32 PNGAPI function png_uint_32 (line 1207) | png_uint_32 PNGAPI function png_alloc_size_t (line 1214) | png_alloc_size_t PNGAPI function png_uint_32 (line 1223) | png_uint_32 PNGAPI function png_uint_32 (line 1229) | png_uint_32 PNGAPI function png_get_palette_max (line 1238) | int PNGAPI FILE: jni/pnginfo.h type png_info_def (line 55) | struct png_info_def FILE: jni/pngmem.c function png_destroy_png_struct (line 24) | void /* PRIVATE */ function png_voidp (line 108) | static png_voidp function png_free (line 231) | void PNGAPI function png_set_mem_fn (line 259) | void PNGAPI function png_voidp (line 275) | png_voidp PNGAPI FILE: jni/pngpread.c function png_process_data (line 35) | void PNGAPI function png_process_data_pause (line 50) | size_t PNGAPI function png_uint_32 (line 77) | png_uint_32 PNGAPI function png_process_some_data (line 93) | void /* PRIVATE */ function png_push_read_sig (line 133) | void /* PRIVATE */ function png_push_read_chunk (line 166) | void /* PRIVATE */ function png_push_fill_buffer (line 420) | void PNGCBAPI function png_push_save_buffer (line 463) | void /* PRIVATE */ function png_push_restore_buffer (line 523) | void /* PRIVATE */ function png_push_read_IDAT (line 533) | void /* PRIVATE */ function png_process_IDAT_data (line 626) | void /* PRIVATE */ function png_push_process_row (line 738) | void /* PRIVATE */ function png_read_push_finish_row (line 968) | void /* PRIVATE */ function png_push_have_info (line 1034) | void /* PRIVATE */ function png_push_have_end (line 1041) | void /* PRIVATE */ function png_push_have_row (line 1048) | void /* PRIVATE */ function png_progressive_combine_row (line 1057) | void PNGAPI function png_set_progressive_read_fn (line 1073) | void PNGAPI function png_voidp (line 1088) | png_voidp PNGAPI FILE: jni/pngpriv.h type png_double (line 372) | typedef struct png_incomplete png_double; type png_double (line 373) | typedef png_double* png_doublep; type png_double (line 374) | typedef const png_double* png_const_doublep; type png_double (line 375) | typedef png_double** png_doublepp; type png_ptruint (line 497) | typedef unsigned long long png_ptruint; type png_ptruint (line 499) | typedef unsigned __int64 png_ptruint; type png_ptruint (line 502) | typedef unsigned long png_ptruint; type png_uint_16p (line 937) | typedef const png_uint_16p * png_const_uint_16pp; type png_control (line 2035) | typedef struct png_control FILE: jni/pngread.c function png_read_info (line 91) | void PNGAPI function png_read_update_info (line 266) | void PNGAPI function png_start_read_image (line 297) | void PNGAPI function png_do_read_intrapixel (line 320) | static void function png_read_row (line 382) | void PNGAPI function png_read_rows (line 644) | void PNGAPI function png_read_image (line 699) | void PNGAPI function else (line 810) | else if ((keep = png_chunk_unknown_handling(png_ptr, chunk_name)) != 0) function else (line 824) | else if (chunk_name == png_IDAT) function png_read_destroy (line 939) | static void function png_destroy_read_struct (line 1010) | void PNGAPI function png_set_read_status_fn (line 1036) | void PNGAPI function png_read_png (line 1048) | void PNGAPI type png_image_read_control (line 1283) | typedef struct function png_image_read_init (line 1305) | static int function png_uint_32 (line 1354) | static png_uint_32 function png_gamma_not_sRGB (line 1387) | static int function png_image_read_header (line 1406) | static int function png_image_begin_read_from_stdio (line 1471) | int PNGAPI function png_image_begin_read_from_file (line 1501) | int PNGAPI function png_image_memory_read (line 1540) | static void PNGCBAPI function png_image_begin_read_from_memory (line 1570) | int PNGAPI png_image_begin_read_from_memory(png_imagep image, function png_image_skip_unused_chunks (line 1608) | static void function set_file_encoding (line 1665) | static void function decode_gamma (line 1685) | static unsigned int function png_uint_32 (line 1724) | static png_uint_32 function png_create_colormap_entry (line 1761) | static void function make_gray_file_colormap (line 1982) | static int function make_gray_colormap (line 1993) | static int function make_ga_colormap (line 2005) | static int function make_rgb_colormap (line 2060) | static int function png_image_read_colormap (line 2089) | static int function png_image_read_and_map (line 2943) | static int function png_image_read_colormapped (line 3132) | static int function png_image_read_composite (line 3264) | static int function png_image_read_background (line 3391) | static int function png_image_read_direct (line 3671) | static int function png_image_finish_read (line 4107) | int PNGAPI FILE: jni/pngrio.c function png_read_data (line 31) | void /* PRIVATE */ function png_default_read_data (line 49) | void PNGCBAPI function png_set_read_fn (line 86) | void PNGAPI FILE: jni/pngrtran.c function png_set_crc_action (line 35) | void PNGAPI function png_rtran_ok (line 109) | static int function png_set_background_fixed (line 136) | void PNGFAPI function png_set_background (line 166) | void PNGAPI function png_set_scale_16 (line 182) | void PNGAPI function png_set_strip_16 (line 196) | void PNGAPI function png_set_strip_alpha (line 209) | void PNGAPI function png_fixed_point (line 222) | static png_fixed_point function png_fixed_point (line 261) | static png_fixed_point function png_set_alpha_mode_fixed (line 286) | void PNGFAPI function png_set_alpha_mode (line 399) | void PNGAPI type png_dsort (line 418) | typedef struct png_dsort_struct type png_dsort (line 424) | typedef png_dsort * png_dsortp; type png_dsort (line 425) | typedef png_dsort * * png_dsortpp; function png_set_quantize (line 427) | void PNGAPI function png_set_gamma_fixed (line 817) | void PNGFAPI function png_set_gamma (line 857) | void PNGAPI function png_set_expand (line 871) | void PNGAPI function png_set_palette_to_rgb (line 901) | void PNGAPI function png_set_expand_gray_1_2_4_to_8 (line 913) | void PNGAPI function png_set_tRNS_to_alpha (line 925) | void PNGAPI function png_set_expand_16 (line 941) | void PNGAPI function png_set_gray_to_rgb (line 954) | void PNGAPI function png_set_rgb_to_gray_fixed (line 969) | void PNGFAPI function png_set_rgb_to_gray (line 1058) | void PNGAPI function png_set_read_user_transform_fn (line 1072) | void PNGAPI function png_gamma_threshold (line 1091) | static int /* PRIVATE */ function png_init_palette_transformations (line 1116) | static void /* PRIVATE */ function png_init_rgb_transformations (line 1205) | static void /* PRIVATE */ function png_init_read_transformations (line 1290) | void /* PRIVATE */ function png_read_transform_info (line 1939) | void /* PRIVATE */ function png_do_unpack (line 2151) | static void function png_do_unshift (line 2249) | static void function png_do_scale_16_to_8 (line 2388) | static void function png_do_chop (line 2446) | static void function png_do_read_swap_alpha (line 2474) | static void function png_do_read_invert_alpha (line 2570) | static void function png_do_read_filler (line 2672) | static void function png_do_gray_to_rgb (line 2859) | static void function png_do_rgb_to_gray (line 2998) | static int function png_do_compose (line 3199) | static void function png_do_gamma (line 3943) | static void function png_do_encode_alpha (line 4144) | static void function png_do_expand_palette (line 4208) | static void function png_do_expand (line 4382) | static void function png_do_expand_16 (line 4612) | static void function png_do_quantize (line 4642) | static void function png_do_read_transformations (line 4739) | void /* PRIVATE */ FILE: jni/pngrutil.c function png_uint_32 (line 21) | png_uint_32 PNGAPI function png_fixed_point (line 40) | static png_fixed_point /* PRIVATE */ function png_read_sig (line 120) | void /* PRIVATE */ function png_uint_32 (line 155) | png_uint_32 /* PRIVATE */ function png_crc_read (line 195) | void /* PRIVATE */ function png_crc_finish (line 210) | int /* PRIVATE */ function png_crc_error (line 250) | int /* PRIVATE */ function png_bytep (line 297) | static png_bytep function png_inflate_claim (line 341) | static int function png_zlib_inflate (line 453) | int /* PRIVATE */ function png_inflate (line 484) | static int function png_decompress_chunk (line 609) | static int function png_inflate_read (line 773) | static int function png_handle_IHDR (line 838) | void /* PRIVATE */ function else (line 1026) | else if (png_crc_error(png_ptr) != 0) /* Only if we have a CRC error */ function png_handle_IEND (line 1099) | void /* PRIVATE */ function png_handle_gAMA (line 1119) | void /* PRIVATE */ function png_handle_sBIT (line 1157) | void /* PRIVATE */ function png_handle_cHRM (line 1239) | void /* PRIVATE */ function png_handle_sRGB (line 1311) | void /* PRIVATE */ function png_handle_iCCP (line 1361) | void /* PRIVATE */ function png_handle_sPLT (line 1639) | void /* PRIVATE */ function png_handle_tRNS (line 1816) | void /* PRIVATE */ function png_handle_bKGD (line 1920) | void /* PRIVATE */ function png_handle_eXIf (line 2038) | void /* PRIVATE */ function png_handle_hIST (line 2101) | void /* PRIVATE */ function png_handle_pHYs (line 2153) | void /* PRIVATE */ function png_handle_oFFs (line 2199) | void /* PRIVATE */ function png_handle_pCAL (line 2246) | void /* PRIVATE */ function png_handle_sCAL (line 2375) | void /* PRIVATE */ function png_handle_tIME (line 2468) | void /* PRIVATE */ function png_handle_tEXt (line 2514) | void /* PRIVATE */ function png_handle_zTXt (line 2595) | void /* PRIVATE */ function png_handle_iTXt (line 2712) | void /* PRIVATE */ function png_cache_unknown_chunk (line 2862) | static int function png_check_chunk_name (line 3133) | void /* PRIVATE */ function png_check_chunk_length (line 3152) | void /* PRIVATE */ function png_combine_row (line 3199) | void /* PRIVATE */ function png_do_read_interlace (line 3683) | void /* PRIVATE */ function png_read_filter_row_sub (line 3930) | static void function png_read_filter_row_up (line 3948) | static void function png_read_filter_row_avg (line 3964) | static void function png_read_filter_row_paeth_1byte_pixel (line 3991) | static void function png_read_filter_row_paeth_multibyte_pixel (line 4042) | static void function png_init_filter_functions (line 4093) | static void function png_read_filter_row (line 4130) | void /* PRIVATE */ function png_read_IDAT_data (line 4148) | void /* PRIVATE */ function png_read_finish_IDAT (line 4277) | void /* PRIVATE */ function png_read_finish_row (line 4325) | void /* PRIVATE */ function png_read_start_row (line 4390) | void /* PRIVATE */ FILE: jni/pngset.c function png_set_bKGD (line 24) | void PNGAPI function png_set_cHRM_fixed (line 39) | void PNGFAPI function png_set_cHRM_XYZ_fixed (line 68) | void PNGFAPI function png_set_cHRM (line 101) | void PNGAPI function png_set_cHRM_XYZ (line 117) | void PNGAPI function png_set_eXIf (line 138) | void PNGAPI function png_set_gAMA_fixed (line 185) | void PNGFAPI function png_set_gAMA (line 199) | void PNGAPI function png_set_hIST (line 209) | void PNGAPI function png_set_IHDR (line 253) | void PNGAPI function png_set_oFFs (line 294) | void PNGAPI function png_set_pCAL (line 311) | void PNGAPI function png_set_sCAL_s (line 429) | void PNGAPI function png_set_sCAL (line 496) | void PNGAPI function png_set_sCAL_fixed (line 526) | void PNGAPI function png_set_pHYs (line 555) | void PNGAPI function png_set_PLTE (line 571) | void PNGAPI function png_set_sBIT (line 637) | void PNGAPI function png_set_sRGB (line 652) | void PNGAPI function png_set_sRGB_gAMA_and_cHRM (line 664) | void PNGAPI function png_set_iCCP (line 687) | void PNGAPI function png_set_text (line 761) | void PNGAPI function png_set_text_2 (line 772) | int /* PRIVATE */ function png_set_tIME (line 967) | void PNGAPI function png_set_tRNS (line 993) | void PNGAPI function png_set_sPLT (line 1061) | void PNGAPI function png_byte (line 1162) | static png_byte function png_set_unknown_chunks (line 1199) | void PNGAPI function png_set_unknown_chunk_location (line 1298) | void PNGAPI function png_uint_32 (line 1328) | png_uint_32 PNGAPI function add_one_chunk (line 1343) | static unsigned int function png_set_keep_unknown_chunks (line 1371) | void PNGAPI function png_set_read_user_chunk_fn (line 1530) | void PNGAPI function png_set_rows (line 1545) | void PNGAPI function png_set_compression_buffer_size (line 1565) | void PNGAPI function png_set_invalid (line 1625) | void PNGAPI function png_set_user_limits (line 1635) | void PNGAPI function png_set_chunk_cache_max (line 1651) | void PNGAPI function png_set_chunk_malloc_max (line 1659) | void PNGAPI function png_set_benign_errors (line 1670) | void PNGAPI function png_set_check_for_invalid_index (line 1700) | void PNGAPI function png_uint_32 (line 1725) | png_uint_32 /* PRIVATE */ FILE: jni/pngstruct.h type png_compression_buffer (line 61) | typedef struct png_compression_buffer type png_xy (line 83) | typedef struct png_xy type png_XYZ (line 94) | typedef struct png_XYZ type png_colorspace (line 112) | typedef struct png_colorspace type png_colorspace (line 128) | typedef const png_colorspace * PNG_RESTRICT type png_struct_def (line 143) | struct png_struct_def FILE: jni/pngtest.c type FILE (line 83) | typedef FILE * png_FILE_p; function tIME_to_str (line 130) | static int function read_row_callback (line 173) | static void PNGCBAPI function write_row_callback (line 198) | static void PNGCBAPI function read_user_callback (line 212) | static void PNGCBAPI function count_zero_samples (line 228) | static void PNGCBAPI function pngtest_check_io_state (line 350) | void function pngtest_read_data (line 388) | static void PNGCBAPI function pngtest_flush (line 414) | static void PNGCBAPI function pngtest_write_data (line 427) | static void PNGCBAPI type pngtest_error_parameters (line 450) | typedef struct function pngtest_warning (line 455) | static void PNGCBAPI function pngtest_error (line 475) | static void PNGCBAPI type memory_information (line 500) | typedef struct memory_information type memory_information (line 506) | typedef memory_information *memory_infop; function png_voidp (line 518) | png_voidp function png_debug_free (line 573) | void PNGCBAPI type user_chunk_data (line 638) | struct user_chunk_data function init_callback_info (line 655) | static void function set_location (line 662) | static int function read_user_chunk_callback (line 691) | static int PNGCBAPI function write_sTER_chunk (line 753) | static void function write_vpAg_chunk (line 764) | static void function write_chunks (line 783) | static void function pngtest_check_text_support (line 814) | static void function test_one_file (line 852) | static int function main (line 1821) | int function main (line 2147) | int type png_libpng_version_1_6_37 (line 2158) | typedef png_libpng_version_1_6_37 Your_png_h_is_not_version_1_6_37; FILE: jni/pngtrans.c function png_set_bgr (line 20) | void PNGAPI function png_set_swap (line 34) | void PNGAPI function png_set_packing (line 49) | void PNGAPI function png_set_packswap (line 69) | void PNGAPI function png_set_shift (line 83) | void PNGAPI function png_set_interlace_handling (line 98) | int PNGAPI function png_set_filler (line 119) | void PNGAPI function png_set_add_alpha (line 204) | void PNGAPI function png_set_swap_alpha (line 222) | void PNGAPI function png_set_invert_alpha (line 236) | void PNGAPI function png_set_invert_mono (line 249) | void PNGAPI function png_do_invert (line 261) | void /* PRIVATE */ function png_do_swap (line 318) | void /* PRIVATE */ function png_do_packswap (line 454) | void /* PRIVATE */ function png_do_strip_channel (line 494) | void /* PRIVATE */ function png_do_bgr (line 618) | void /* PRIVATE */ function png_do_check_palette_indexes (line 698) | void /* PRIVATE */ function png_set_user_transform_info (line 801) | void PNGAPI function png_voidp (line 832) | png_voidp PNGAPI function png_uint_32 (line 843) | png_uint_32 PNGAPI function png_byte (line 855) | png_byte PNGAPI FILE: jni/pngwio.c function png_write_data (line 32) | void /* PRIVATE */ function png_default_write_data (line 50) | void PNGCBAPI function png_flush (line 70) | void /* PRIVATE */ function png_default_flush (line 78) | void PNGCBAPI function png_set_write_fn (line 121) | void PNGAPI FILE: jni/pngwrite.c function write_unknown_chunks (line 23) | static void function png_write_info_before_PLTE (line 83) | void PNGAPI function png_write_info (line 191) | void PNGAPI function png_write_end (line 357) | void PNGAPI function png_convert_from_struct_tm (line 471) | void PNGAPI function png_convert_from_time_t (line 484) | void PNGAPI function png_write_rows (line 578) | void PNGAPI function png_write_image (line 600) | void PNGAPI function png_do_write_intrapixel (line 633) | static void function png_write_row (line 697) | void PNGAPI function png_set_flush (line 907) | void PNGAPI function png_write_flush (line 919) | void PNGAPI function png_write_destroy (line 938) | static void function png_destroy_write_struct (line 978) | void PNGAPI function png_set_filter (line 999) | void PNGAPI function PNG_UNUSED (line 1133) | PNG_UNUSED(png_ptr) function png_set_compression_level (line 1157) | void PNGAPI function png_set_compression_mem_level (line 1168) | void PNGAPI function png_set_compression_strategy (line 1179) | void PNGAPI function png_set_compression_window_bits (line 1196) | void PNGAPI function png_set_compression_method (line 1223) | void PNGAPI function png_set_text_compression_level (line 1243) | void PNGAPI function png_set_text_compression_mem_level (line 1254) | void PNGAPI function png_set_text_compression_strategy (line 1265) | void PNGAPI function png_set_text_compression_window_bits (line 1279) | void PNGAPI function png_set_text_compression_method (line 1300) | void PNGAPI function png_set_write_status_fn (line 1316) | void PNGAPI function png_set_write_user_transform_fn (line 1326) | void PNGAPI function png_write_png (line 1342) | void PNGAPI function png_image_write_init (line 1467) | static int type png_image_write_control (line 1505) | typedef struct function png_write_image_16bit (line 1527) | static int function png_byte (line 1641) | static png_byte function png_write_image_8bit (line 1686) | static int function png_image_set_PLTE (line 1783) | static void function png_image_write_main (line 1929) | static int function png_image_write_memory (line 2195) | static int function png_image_write_to_memory (line 2211) | int PNGAPI function png_image_write_to_stdio (line 2278) | int PNGAPI function png_image_write_to_file (line 2327) | int PNGAPI FILE: jni/pngwtran.c function png_do_pack (line 24) | static void function png_do_shift (line 171) | static void function png_do_write_swap_alpha (line 309) | static void function png_do_write_invert_alpha (line 403) | static void function png_do_write_transformations (line 500) | void /* PRIVATE */ FILE: jni/pngwutil.c function png_save_uint_32 (line 23) | void PNGAPI function png_save_uint_16 (line 36) | void PNGAPI function png_write_sig (line 50) | void PNGAPI function png_write_chunk_header (line 72) | static void function png_write_chunk_start (line 114) | void PNGAPI function png_write_chunk_data (line 126) | void PNGAPI function png_write_chunk_end (line 145) | void PNGAPI function png_write_complete_chunk (line 174) | static void function png_write_chunk (line 191) | void PNGAPI function png_alloc_size_t (line 203) | static png_alloc_size_t function optimize_cmf (line 249) | static void function png_deflate_claim (line 291) | static int function png_free_buffer_list (line 438) | void /* PRIVATE */ type compression_state (line 469) | typedef struct function png_text_compress_init (line 477) | static void function png_text_compress (line 487) | static int function png_write_compressed_data_out (line 636) | static void function png_write_IHDR (line 671) | void /* PRIVATE */ function png_write_PLTE (line 841) | void /* PRIVATE */ function png_compress_IDAT (line 930) | void /* PRIVATE */ function png_write_IEND (line 1072) | void /* PRIVATE */ function png_write_gAMA_fixed (line 1083) | void /* PRIVATE */ function png_write_sRGB (line 1098) | void /* PRIVATE */ function png_write_iCCP (line 1116) | void /* PRIVATE */ function png_write_sPLT (line 1178) | void /* PRIVATE */ function png_write_sBIT (line 1262) | void /* PRIVATE */ function png_write_cHRM_fixed (line 1321) | void /* PRIVATE */ function png_write_tRNS (line 1347) | void /* PRIVATE */ function png_write_bKGD (line 1413) | void /* PRIVATE */ function png_write_eXIf (line 1476) | void /* PRIVATE */ function png_write_hIST (line 1498) | void /* PRIVATE */ function png_write_tEXt (line 1529) | void /* PRIVATE */ function png_write_zTXt (line 1572) | void /* PRIVATE */ function png_write_iTXt (line 1623) | void /* PRIVATE */ function png_write_oFFs (line 1723) | void /* PRIVATE */ function png_write_pCAL (line 1743) | void /* PRIVATE */ function png_write_sCAL_s (line 1808) | void /* PRIVATE */ function png_write_pHYs (line 1838) | void /* PRIVATE */ function png_write_tIME (line 1862) | void /* PRIVATE */ function png_write_start_row (line 1889) | void /* PRIVATE */ function png_write_finish_row (line 2004) | void /* PRIVATE */ function png_do_write_interlace (line 2095) | void /* PRIVATE */ function png_setup_sub_row (line 2278) | static size_t /* PRIVATE */ function png_setup_sub_row_only (line 2317) | static void /* PRIVATE */ function png_setup_up_row (line 2339) | static size_t /* PRIVATE */ function png_setup_up_row_only (line 2366) | static void /* PRIVATE */ function png_setup_avg_row (line 2382) | static size_t /* PRIVATE */ function png_setup_avg_row_only (line 2422) | static void /* PRIVATE */ function png_setup_paeth_row (line 2444) | static size_t /* PRIVATE */ function png_setup_paeth_row_only (line 2505) | static void /* PRIVATE */ function png_write_find_filter (line 2549) | void /* PRIVATE */ function png_write_filtered_row (line 2746) | static void
Condensed preview — 38 files, each showing path, character count, and a content snippet. Download the .json file or copy for the full structured content (1,468K chars).
[
{
"path": ".gitattributes",
"chars": 12,
"preview": "* text=auto\n"
},
{
"path": ".gitignore",
"chars": 14,
"preview": ".DS_Store\nobj\n"
},
{
"path": "CMakeLists.txt",
"chars": 2328,
"preview": "cmake_minimum_required( VERSION 3.6 )\n\nset( project_name png )\nproject( ${project_name} )\n\nif( MSVC )\n add_definition"
},
{
"path": "LICENSE",
"chars": 4202,
"preview": "\nThis copy of the libpng notices is provided for your convenience. In case of\nany discrepancy between this copy and the"
},
{
"path": "README.rst",
"chars": 762,
"preview": "libpng for Android \n==================\nThis is a repackaging of libpng 1.6.37 for Android.\n\nMost changes went in config."
},
{
"path": "build.sh",
"chars": 43,
"preview": "#!/bin/sh\nndk-build NDK_PROJECT_PATH=./ $@\n"
},
{
"path": "jni/Android.mk",
"chars": 592,
"preview": "LOCAL_PATH := $(call my-dir)\ninclude $(CLEAR_VARS)\n\nLOCAL_CFLAGS :=\n\nLOCAL_MODULE := libpng\nLOCAL_SRC_FILES :=\\\n\tpng."
},
{
"path": "jni/Application.mk",
"chars": 91,
"preview": "APP_OPTIM := release\nAPP_ABI := armeabi-v7a arm64-v8a x86_64 # or all\nAPP_MODULES := libpng"
},
{
"path": "jni/arm/arm_init.c",
"chars": 4682,
"preview": "\n/* arm_init.c - NEON optimised filter functions\n *\n * Copyright (c) 2018 Cosmin Truta\n * Copyright (c) 2014,2016 Glenn "
},
{
"path": "jni/arm/filter_neon.S",
"chars": 8352,
"preview": "\n/* filter_neon.S - NEON optimised filter functions\n *\n * Copyright (c) 2018 Cosmin Truta\n * Copyright (c) 2014,2017 Gle"
},
{
"path": "jni/arm/filter_neon_intrinsics.c",
"chars": 11814,
"preview": "\n/* filter_neon_intrinsics.c - NEON optimised filter functions\n *\n * Copyright (c) 2018 Cosmin Truta\n * Copyright (c) 20"
},
{
"path": "jni/arm/palette_neon_intrinsics.c",
"chars": 4608,
"preview": "\n/* palette_neon_intrinsics.c - NEON optimised palette expansion functions\n *\n * Copyright (c) 2018-2019 Cosmin Truta\n *"
},
{
"path": "jni/config.h",
"chars": 2470,
"preview": "/* config.h. Generated from config.h.in by configure. */\n/* config.h.in. Generated from configure.ac by autoheader. "
},
{
"path": "jni/example.c",
"chars": 40399,
"preview": "\n#if 0 /* in case someone actually tries to compile this */\n\n/* example.c - an example of using libpng\n *\n * Maintained "
},
{
"path": "jni/png.c",
"chars": 157413,
"preview": "\n/* png.c - location for general purpose libpng functions\n *\n * Copyright (c) 2018-2019 Cosmin Truta\n * Copyright (c) 19"
},
{
"path": "jni/png.h",
"chars": 142860,
"preview": "\n/* png.h - header file for PNG reference library\n *\n * libpng version 1.6.37 - April 14, 2019\n *\n * Copyright (c) 2018-"
},
{
"path": "jni/pngconf.h",
"chars": 22846,
"preview": "\n/* pngconf.h - machine-configurable file for libpng\n *\n * libpng version 1.6.37\n *\n * Copyright (c) 2018-2019 Cosmin Tr"
},
{
"path": "jni/pngdebug.h",
"chars": 5319,
"preview": "\n/* pngdebug.h - Debugging macros for libpng, also used in pngtest.c\n *\n * Copyright (c) 2018 Cosmin Truta\n * Copyright "
},
{
"path": "jni/pngerror.c",
"chars": 29168,
"preview": "\n/* pngerror.c - stub functions for i/o and memory allocation\n *\n * Copyright (c) 2018 Cosmin Truta\n * Copyright (c) 199"
},
{
"path": "jni/pngget.c",
"chars": 34032,
"preview": "\n/* pngget.c - retrieval of values from info struct\n *\n * Copyright (c) 2018 Cosmin Truta\n * Copyright (c) 1998-2002,200"
},
{
"path": "jni/pnginfo.h",
"chars": 12514,
"preview": "\n/* pnginfo.h - header file for PNG reference library\n *\n * Copyright (c) 2018 Cosmin Truta\n * Copyright (c) 1998-2002,2"
},
{
"path": "jni/pnglibconf.h",
"chars": 7652,
"preview": "/* libpng 1.6.23 STANDARD API DEFINITION */\r\n\r\n/* pnglibconf.h - library build configuration */\r\n\r\n/* Libpng version 1.6"
},
{
"path": "jni/pngmem.c",
"chars": 8323,
"preview": "\n/* pngmem.c - stub functions for memory allocation\n *\n * Copyright (c) 2018 Cosmin Truta\n * Copyright (c) 1998-2002,200"
},
{
"path": "jni/pngpread.c",
"chars": 31706,
"preview": "\n/* pngpread.c - read a png file in push mode\n *\n * Copyright (c) 2018 Cosmin Truta\n * Copyright (c) 1998-2002,2004,2006"
},
{
"path": "jni/pngpriv.h",
"chars": 89768,
"preview": "\n/* pngpriv.h - private declarations for use inside libpng\n *\n * Copyright (c) 2018-2019 Cosmin Truta\n * Copyright (c) 1"
},
{
"path": "jni/pngread.c",
"chars": 142337,
"preview": "\n/* pngread.c - read a PNG file\n *\n * Copyright (c) 2018-2019 Cosmin Truta\n * Copyright (c) 1998-2002,2004,2006-2018 Gle"
},
{
"path": "jni/pngrio.c",
"chars": 3898,
"preview": "\n/* pngrio.c - functions for data input\n *\n * Copyright (c) 2018 Cosmin Truta\n * Copyright (c) 1998-2002,2004,2006-2016,"
},
{
"path": "jni/pngrtran.c",
"chars": 167439,
"preview": "\n/* pngrtran.c - transforms the data in a row for PNG readers\n *\n * Copyright (c) 2018-2019 Cosmin Truta\n * Copyright (c"
},
{
"path": "jni/pngrutil.c",
"chars": 147465,
"preview": "\n/* pngrutil.c - utilities to read a PNG file\n *\n * Copyright (c) 2018 Cosmin Truta\n * Copyright (c) 1998-2002,2004,2006"
},
{
"path": "jni/pngset.c",
"chars": 51373,
"preview": "\n/* pngset.c - storage of image information into info struct\n *\n * Copyright (c) 2018 Cosmin Truta\n * Copyright (c) 1998"
},
{
"path": "jni/pngstruct.h",
"chars": 20198,
"preview": "\n/* pngstruct.h - header file for PNG reference library\n *\n * Copyright (c) 2018-2019 Cosmin Truta\n * Copyright (c) 1998"
},
{
"path": "jni/pngtest.c",
"chars": 62815,
"preview": "\n/* pngtest.c - a simple test program to test libpng\n *\n * Copyright (c) 2018-2019 Cosmin Truta\n * Copyright (c) 1998-20"
},
{
"path": "jni/pngtrans.c",
"chars": 25240,
"preview": "\n/* pngtrans.c - transforms the data in a row (used by both readers and writers)\n *\n * Copyright (c) 2018 Cosmin Truta\n "
},
{
"path": "jni/pngwio.c",
"chars": 5601,
"preview": "\n/* pngwio.c - functions for data output\n *\n * Copyright (c) 2018 Cosmin Truta\n * Copyright (c) 1998-2002,2004,2006-2014"
},
{
"path": "jni/pngwrite.c",
"chars": 76428,
"preview": "\n/* pngwrite.c - general routines to write a PNG file\n *\n * Copyright (c) 2018-2019 Cosmin Truta\n * Copyright (c) 1998-2"
},
{
"path": "jni/pngwtran.c",
"chars": 15337,
"preview": "\n/* pngwtran.c - transforms the data in a row for PNG writers\n *\n * Copyright (c) 2018 Cosmin Truta\n * Copyright (c) 199"
},
{
"path": "jni/pngwutil.c",
"chars": 80350,
"preview": "\n/* pngwutil.c - utilities to write a PNG file\n *\n * Copyright (c) 2018 Cosmin Truta\n * Copyright (c) 1998-2002,2004,200"
},
{
"path": "png-config.cmake.in",
"chars": 61,
"preview": "include( ${CMAKE_CURRENT_LIST_DIR}/@PNG_EXPORT_NAME@.cmake )\n"
}
]
About this extraction
This page contains the full source code of the julienr/libpng-android GitHub repository, extracted and formatted as plain text for AI agents and large language models (LLMs). The extraction includes 38 files (1.4 MB), approximately 377.7k tokens, and a symbol index with 649 extracted functions, classes, methods, constants, and types. Use this with OpenClaw, Claude, ChatGPT, Cursor, Windsurf, or any other AI tool that accepts text input. You can copy the full output to your clipboard or download it as a .txt file.
Extracted by GitExtract — free GitHub repo to text converter for AI. Built by Nikandr Surkov.