Repository: Curzibn/Luban Branch: master Commit: 4beebb90ce38 Files: 71 Total size: 288.2 KB Directory structure: gitextract_rqio205u/ ├── .github/ │ └── workflows/ │ └── android.yml ├── .gitignore ├── LICENSE ├── README.md ├── README_EN.md ├── app/ │ ├── .gitignore │ ├── build.gradle.kts │ ├── proguard-rules.pro │ └── src/ │ ├── androidTest/ │ │ └── java/ │ │ └── top/ │ │ └── zibin/ │ │ └── luban/ │ │ └── app/ │ │ └── ExampleInstrumentedTest.kt │ ├── main/ │ │ ├── AndroidManifest.xml │ │ ├── java/ │ │ │ └── top/ │ │ │ └── zibin/ │ │ │ └── luban/ │ │ │ └── app/ │ │ │ ├── MainActivity.kt │ │ │ ├── MainViewModel.kt │ │ │ └── ui/ │ │ │ └── theme/ │ │ │ ├── Color.kt │ │ │ ├── Theme.kt │ │ │ └── Type.kt │ │ └── res/ │ │ ├── drawable/ │ │ │ ├── ic_launcher_background.xml │ │ │ └── ic_launcher_foreground.xml │ │ ├── mipmap-anydpi/ │ │ │ ├── ic_launcher.xml │ │ │ └── ic_launcher_round.xml │ │ ├── values/ │ │ │ ├── colors.xml │ │ │ ├── strings.xml │ │ │ └── themes.xml │ │ └── xml/ │ │ ├── backup_rules.xml │ │ └── data_extraction_rules.xml │ └── test/ │ └── java/ │ └── top/ │ └── zibin/ │ └── luban/ │ └── app/ │ └── ExampleUnitTest.kt ├── app-java/ │ ├── .gitignore │ ├── build.gradle.kts │ ├── proguard-rules.pro │ └── src/ │ ├── androidTest/ │ │ └── java/ │ │ └── top/ │ │ └── zibin/ │ │ └── luban/ │ │ └── app/ │ │ └── java/ │ │ └── ExampleInstrumentedTest.java │ ├── main/ │ │ ├── AndroidManifest.xml │ │ ├── java/ │ │ │ └── top/ │ │ │ └── zibin/ │ │ │ └── luban/ │ │ │ └── app/ │ │ │ └── java/ │ │ │ └── MainActivity.java │ │ └── res/ │ │ ├── drawable/ │ │ │ ├── ic_launcher_background.xml │ │ │ └── ic_launcher_foreground.xml │ │ ├── layout/ │ │ │ └── activity_main.xml │ │ ├── mipmap-anydpi/ │ │ │ ├── ic_launcher.xml │ │ │ └── ic_launcher_round.xml │ │ ├── values/ │ │ │ ├── colors.xml │ │ │ ├── strings.xml │ │ │ └── themes.xml │ │ ├── values-night/ │ │ │ └── themes.xml │ │ └── xml/ │ │ ├── backup_rules.xml │ │ └── data_extraction_rules.xml │ └── test/ │ └── java/ │ └── top/ │ └── zibin/ │ └── luban/ │ └── app/ │ └── java/ │ └── ExampleUnitTest.java ├── build.gradle.kts ├── gradle/ │ ├── libs.versions.toml │ └── wrapper/ │ ├── gradle-wrapper.jar │ └── gradle-wrapper.properties ├── gradle.properties ├── gradlew ├── gradlew.bat ├── luban/ │ ├── .gitignore │ ├── build.gradle.kts │ ├── consumer-rules.pro │ ├── proguard-rules.pro │ └── src/ │ ├── androidTest/ │ │ └── java/ │ │ └── top/ │ │ └── zibin/ │ │ └── luban/ │ │ └── ExampleInstrumentedTest.kt │ ├── main/ │ │ ├── AndroidManifest.xml │ │ ├── cpp/ │ │ │ ├── CMakeLists.txt │ │ │ ├── turbojpeg.h │ │ │ └── turbojpeg_wrapper.cpp │ │ └── java/ │ │ └── top/ │ │ └── zibin/ │ │ └── luban/ │ │ ├── algorithm/ │ │ │ └── CompressionCalculator.kt │ │ ├── api/ │ │ │ ├── CompressionTask.kt │ │ │ ├── Luban.kt │ │ │ ├── LubanCompat.kt │ │ │ └── OnCompressListener.kt │ │ ├── compression/ │ │ │ ├── Compressor.kt │ │ │ ├── JpegCompressor.kt │ │ │ └── TurboJpegNative.kt │ │ └── io/ │ │ └── ImageLoader.kt │ └── test/ │ └── java/ │ └── top/ │ └── zibin/ │ └── luban/ │ ├── CompressionCalculatorTest.kt │ └── ExampleUnitTest.kt └── settings.gradle.kts ================================================ FILE CONTENTS ================================================ ================================================ FILE: .github/workflows/android.yml ================================================ name: Android CI on: push: branches: [ "master", "main" ] pull_request: branches: [ "master", "main" ] jobs: build: runs-on: ubuntu-latest steps: - name: Checkout code uses: actions/checkout@v4 - name: Set up JDK 17 uses: actions/setup-java@v4 with: java-version: '17' distribution: 'temurin' cache: gradle - name: Set up Android SDK uses: android-actions/setup-android@v3 - name: Grant execute permission for gradlew run: chmod +x gradlew - name: Build with Gradle run: ./gradlew build - name: Run Unit Tests run: ./gradlew test ================================================ FILE: .gitignore ================================================ *.iml .gradle /local.properties /.idea/caches /.idea/libraries /.idea/modules.xml /.idea/workspace.xml /.idea/navEditor.xml /.idea/assetWizardSettings.xml .DS_Store /build /captures .externalNativeBuild .cxx local.properties .idea/ docs/ ================================================ FILE: LICENSE ================================================ Apache License Version 2.0, January 2004 http://www.apache.org/licenses/ TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 1. 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See the License for the specific language governing permissions and limitations under the License. ================================================ FILE: README.md ================================================ # Luban 2 [![License](https://img.shields.io/badge/license-Apache%202.0-blue.svg)](LICENSE) [![Maven Central](https://img.shields.io/maven-central/v/top.zibin/luban.svg?label=Maven%20Central)](https://search.maven.org/search?q=g:top.zibin%20a:luban) [![API](https://img.shields.io/badge/API-21%2B-brightgreen.svg?style=flat)](https://android-arsenal.com/api?level=21) [中文](README.md) | [English](README_EN.md) Luban 2(鲁班 2) —— 高效简洁的 Android 图片压缩工具库,像素级还原微信朋友圈压缩策略。 ## 📑 目录 - [📖 项目描述](#-项目描述) - [📊 效果与对比](#-效果与对比) - [🔬 核心算法特性](#-核心算法特性) - [📦 导入](#-导入) - [💻 使用](#-使用) - [⚡ Kotlin (Coroutines)](#-kotlin-coroutines) - [☕ Java / Builder 模式](#-java--builder-模式) - [☕ 捐助](#-捐助) - [📄 License](#-license) # 📖 项目描述 目前做`App`开发总绕不开图片这个元素。但是随着手机拍照分辨率的提升,图片的压缩成为一个很重要的问题。单纯对图片进行裁切,压缩已经有很多文章介绍。但是裁切成多少,压缩成多少却很难控制好,裁切过头图片太小,质量压缩过头则显示效果太差。 于是自然想到`App`巨头"微信"会是怎么处理,`Luban`(鲁班)就是通过在微信朋友圈发送近100张不同分辨率图片,对比原图与微信压缩后的图片逆向推算出来的压缩算法。 因为是逆向推算,效果还没法跟微信一模一样,但是已经很接近微信朋友圈压缩后的效果,具体看以下对比! 本库是 `Luban` 的 **Kotlin 重构版本**,在升级核心算法的同时,利用 **Kotlin Coroutines** 和 **TurboJPEG** 进行了深度优化。新算法比原算法更加健壮和高效,提供更高效的异步处理和更优质的压缩效果。 # 📊 效果与对比 | 图片类型 | 原图(分辨率, 大小) | Luban(分辨率, 大小) | Wechat(分辨率, 大小) | | :--- | :--- | :--- | :--- | | **标准拍照** | 3024×4032, 5.10MB | 1440×1920, 305KB | 1440×1920, 303KB | | **高清大图** | 4000×6000, 12.10MB | 1440×2160, 318KB | 1440×2160, 305KB | | **2K 截图** | 1440×3200, 2.10MB | 1440×3200, 148KB | 1440×3200, 256KB | | **超长记录** | 1242×22080, 6.10MB | 758×13490, 290KB | 744×13129, 256KB | | **全景横图** | 12000×5000, 8.10MB | 1440×600, 126KB | 1440×600, 123KB | | **设计原稿** | 6000×6000, 6.90MB | 1440×1440, 263KB | 1440×1440, 279KB | ## 🔬 核心算法特性 本库采用**自适应统一图像压缩算法 (Adaptive Unified Image Compression)**,通过原图的分辨率特征,动态应用差异化策略,实现画质与体积的最优平衡。 ### 智能分辨率决策 - **高清基准 (1440p)**:默认以 1440px 作为短边基准,确保在现代 2K/4K 屏幕上的视觉清晰度 - **全景墙策略**:自动识别超大全景图(长边 >10800px),锁定长边为 1440px,保留完整视野 - **超大像素陷阱**:对超过 4096万像素的超高像素图自动执行 1/4 降采样处理 - **长图内存保护**:针对超长截图建立 10.24MP 像素上限,通过等比缩放防止 OOM ### 自适应比特率控制 - **极小图 (<0.5MP)**:几乎不进行有损压缩,防止压缩伪影 - **高频信息图 (0.5-1MP)**:提高编码质量,补偿分辨率损失 - **标准图片 (1-3MP)**:应用平衡系数,对标主流社交软件体验 - **超大图/长图 (>3MP)**:应用高压缩率,显著减少体积 ### 健壮性保障 - **膨胀回退**:压缩后体积大于原图时,自动透传原图,确保绝不"负优化" - **智能格式透传**:保留小体积 PNG 的透明通道,大体积 PNG 自动转码为 JPEG - **输入防御**:妥善处理极端分辨率输入(0、负数、1px 等),防止崩溃 # 📦 导入 确保项目的 `build.gradle` 或 `build.gradle.kts` 已配置 Maven Central 仓库: ```kotlin repositories { mavenCentral() } ``` 在模块的构建文件中添加依赖: **Kotlin DSL (`build.gradle.kts`):** ```kotlin dependencies { implementation("top.zibin:luban:2.0.1") } ``` **Groovy (`build.gradle`):** ```groovy dependencies { implementation 'top.zibin:luban:2.0.1' } ``` > 注意:请访问 [Maven Central](https://search.maven.org/search?q=g:top.zibin%20a:luban) 查看最新版本号。 # 💻 使用 ### ⚡ Kotlin (Coroutines) Luban 提供了三种 Kotlin 调用方式,从最符合 Kotlin 习惯到传统方式: #### 1. DSL 风格(推荐) 最符合 Kotlin 习惯的方式是使用 DSL API: ```kotlin lifecycleScope.launch { val results = luban(context) { outputDir = File(context.cacheDir, "compressed") compress(imageUri1) compress(imageUri2) compress(imageFile1) compress(listOf(imageFile2, imageFile3)) compress(listOf(imageUri3, imageUri4)) } results.forEach { result -> result.getOrNull()?.let { file -> Log.d("Luban", "压缩成功: ${file.absolutePath}") } ?: run { val error = result.exceptionOrNull() Log.e("Luban", "压缩失败: ${error?.message}") } } } ``` **注意:** - 对于 `Uri` 类型的压缩,如果不指定 `outputDir`,默认使用 `context.cacheDir`。对于 `File` 类型的压缩,必须显式设置 `outputDir`。 - DSL 配置是声明式的,配置顺序不影响结果。你可以先设置 `outputDir` 再调用 `compress()`,也可以先调用 `compress()` 再设置 `outputDir`。 #### 2. 扩展函数 你也可以使用扩展函数,获得更流畅的 API: ```kotlin lifecycleScope.launch { val result = imageUri.compressTo(context) result.getOrElse { error -> Log.e("Luban", "压缩失败: ${error.message}") return@launch }.let { file -> Log.d("Luban", "压缩成功: ${file.absolutePath}") } } ``` **压缩单个文件:** ```kotlin val result = inputFile.compressTo(outputDir) ``` **压缩到指定文件:** ```kotlin val result = inputFile.compressToFile(outputFile) ``` **批量压缩:** ```kotlin val results = fileList.compressTo(outputDir) val results = uriList.compressTo(context) ``` #### 3. 传统静态方法 使用传统静态方法: ```kotlin lifecycleScope.launch { val result = Luban.compress(context, inputUri, outputDir) result.getOrElse { error -> Log.e("Luban", "压缩失败: ${error.message}") return@launch }.let { file -> Log.d("Luban", "压缩成功: ${file.absolutePath}") } } ``` **可用方法:** - `Luban.compress(context, input: Uri, outputDir: File = context.cacheDir): Result` - `Luban.compress(input: File, outputDir: File): Result` - `Luban.compressToFile(input: File, output: File): Result` - `Luban.compress(context, inputs: List, outputDir: File = context.cacheDir): List>` - `Luban.compress(inputs: List, outputDir: File): List>` **在其他协程作用域中使用:** ```kotlin val scope = CoroutineScope(Dispatchers.Main + SupervisorJob()) scope.launch { val result = Luban.compress(context, inputUri) result.getOrElse { error -> // 处理错误 return@launch }.let { file -> // 处理成功 } } ``` ### ☕ Java / Builder 模式 对于 Java 项目或偏好回调风格的开发者,可以使用兼容旧版风格的 `Luban.with()` API。 #### 压缩单张图片 ```java Luban.with(context) .load(imageFile) // 支持 File, Uri, 或 String 路径 .setTargetDir(context.getCacheDir()) .bindLifecycle(lifecycleOwner) // 可选:页面销毁时自动取消 .setCompressListener(new OnCompressListener() { @Override public void onStart() { // 开始压缩 } @Override public void onSuccess(File file) { // 压缩成功 } @Override public void onError(Throwable e) { // 发生错误 } }) .launch(); ``` #### 压缩多张图片 ```java List imagePaths = ...; // 图片路径列表 Luban.with(context) .load(imagePaths) // 加载图片列表 .setTargetDir(context.getCacheDir()) .setCompressListener(new OnCompressListener() { @Override public void onStart() { // 开始压缩 } @Override public void onSuccess(File file) { // 每张图片压缩成功后都会回调一次 Log.d("Luban", "Compressed: " + file.getAbsolutePath()); } @Override public void onError(Throwable e) { // 发生错误 } }) .launch(); ``` # ☕ 捐助 如果这个项目对您有帮助,欢迎通过以下方式支持我的工作。您的支持是我持续改进和维护这个项目的动力。
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感谢您的支持!🙏 # 📄 License Copyright 2025 郑梓斌 Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. ================================================ FILE: README_EN.md ================================================ # Luban 2 [![License](https://img.shields.io/badge/license-Apache%202.0-blue.svg)](LICENSE) [![Maven Central](https://img.shields.io/maven-central/v/top.zibin/luban.svg?label=Maven%20Central)](https://search.maven.org/search?q=g:top.zibin%20a:luban) [![API](https://img.shields.io/badge/API-21%2B-brightgreen.svg?style=flat)](https://android-arsenal.com/api?level=21) [English](README_EN.md) | [中文](README.md) Luban 2 — An efficient and concise Android image compression library that closely replicates the compression strategy of WeChat Moments. ## 📑 Table of Contents - [📖 Project Description](#-project-description) - [📊 Effects & Comparison](#-effects--comparison) - [🔬 Core Algorithm Features](#-core-algorithm-features) - [📦 Import](#-import) - [💻 Usage](#-usage) - [⚡ Kotlin (Coroutines)](#-kotlin-coroutines) - [☕ Java / Builder Pattern](#-java--builder-pattern) - [☕ Donation](#-donation) - [📄 License](#-license) # 📖 Project Description Images are an essential part of app development. With the increasing resolution of mobile cameras, image compression has become a critical issue. While there are many articles on simple cropping and compression, choosing the right crop and compression levels is tricky—cropping too much results in tiny images, while over-compressing leads to poor display quality. Naturally, one wonders how the industry giant "WeChat" handles this. `Luban` was derived by reverse-engineering WeChat Moments’ behavior: we sent nearly 100 images with different resolutions and compared the originals with WeChat’s outputs to infer the compression strategy. Since this behavior is inferred from observation, the results may not match WeChat exactly, but they are very close. See the comparison below! This library is the **Kotlin refactored version** of `Luban`. While upgrading the core algorithm, it is optimized with **Kotlin Coroutines** and **TurboJPEG** for faster processing and better output quality. The new algorithm is more robust and efficient than the original, providing more efficient asynchronous processing and superior compression quality. # 📊 Effects & Comparison | Image Type | Original | Luban | WeChat | | :--- | :--- | :--- | :--- | | **Standard Photo** | 3024×4032, 5.10MB | 1440×1920, 305KB | 1440×1920, 303KB | | **High-Res Photo** | 4000×6000, 12.10MB | 1440×2160, 318KB | 1440×2160, 305KB | | **2K Screenshot** | 1440×3200, 2.10MB | 1440×3200, 148KB | 1440×3200, 256KB | | **Long Screenshot** | 1242×22080, 6.10MB | 758×13490, 290KB | 744×13129, 256KB | | **Panorama** | 12000×5000, 8.10MB | 1440×600, 126KB | 1440×600, 123KB | | **Design Draft** | 6000×6000, 6.90MB | 1440×1440, 263KB | 1440×1440, 279KB | ## 🔬 Core Algorithm Features This library uses an **Adaptive Unified Image Compression** algorithm that dynamically applies differentiated strategies based on the original image's resolution characteristics to achieve optimal balance between quality and file size. ### Intelligent Resolution Decision - **High-Definition Baseline (1440p)**: Uses 1440px as the default short-side baseline, ensuring visual clarity on modern 2K/4K displays - **Panorama Wall Strategy**: Automatically identifies ultra-wide panoramas (long side >10800px), locks the long side to 1440px while preserving the full field of view - **Mega-Pixel Trap**: Automatically applies 1/4 downsampling to images exceeding 41 megapixels (≈40.96 MP) - **Long Image Memory Protection**: Establishes a 10.24MP pixel cap for ultra-long screenshots, reducing the risk of out-of-memory (OOM) errors through proportional scaling ### Adaptive Bitrate Control - **Tiny Images (<0.5MP)**: Minimal lossy compression to prevent compression artifacts - **High-Frequency Images (0.5-1MP)**: Enhanced encoding quality to compensate for resolution loss - **Standard Images (1-3MP)**: Balanced coefficients matching mainstream social media apps - **Large/Long Images (>3MP)**: High compression ratios to significantly reduce file size ### Robustness Guarantees - **Inflation Fallback**: Automatically returns the original image if compressed size exceeds original, avoiding making files larger after compression - **Smart Format Passthrough**: Preserves transparency for small PNG files, and converts large PNG files to JPEG when appropriate - **Input Defense**: Safely handles extreme resolution inputs (0, negative, 1px, etc.), preventing crashes # 📦 Import Make sure `mavenCentral()` is included in your repositories. Add the dependency to your module's `build.gradle.kts` file: ```kotlin dependencies { implementation("top.zibin:luban:2.0.1") } ``` # 💻 Usage ### ⚡ Kotlin (Coroutines) Luban provides three ways to use the library in Kotlin, from most idiomatic to traditional: #### 1. DSL Style (Recommended) The most Kotlin-idiomatic way is using the DSL API: ```kotlin lifecycleScope.launch { val results = luban(context) { outputDir = File(context.cacheDir, "compressed") compress(imageUri1) compress(imageUri2) compress(imageFile1) compress(listOf(imageFile2, imageFile3)) compress(listOf(imageUri3, imageUri4)) } results.forEach { result -> result.getOrNull()?.let { file -> Log.d("Luban", "Compressed: ${file.absolutePath}") } ?: run { val error = result.exceptionOrNull() Log.e("Luban", "Error: ${error?.message}") } } } ``` **Note:** - For `Uri` compression, if `outputDir` is not specified, it defaults to `context.cacheDir`. For `File` compression, `outputDir` must be explicitly set. - The DSL configuration is declarative, so the order of configuration does not affect the result. You can set `outputDir` before calling `compress()`, or call `compress()` before setting `outputDir`. #### 2. Extension Functions You can also use extension functions for a more fluent API: ```kotlin lifecycleScope.launch { val result = imageUri.compressTo(context) result.getOrElse { error -> Log.e("Luban", "Error: ${error.message}") return@launch }.let { file -> Log.d("Luban", "Compressed: ${file.absolutePath}") } } ``` **Compress a single file:** ```kotlin val result = inputFile.compressTo(outputDir) ``` **Compress to a specific output file:** ```kotlin val result = inputFile.compressToFile(outputFile) ``` **Compress multiple files:** ```kotlin val results = fileList.compressTo(outputDir) val results = uriList.compressTo(context) ``` #### 3. Traditional Static Methods The traditional way using static methods: ```kotlin lifecycleScope.launch { val result = Luban.compress(context, inputUri, outputDir) result.getOrElse { error -> Log.e("Luban", "Error: ${error.message}") return@launch }.let { file -> Log.d("Luban", "Compressed: ${file.absolutePath}") } } ``` **Available methods:** - `Luban.compress(context, input: Uri, outputDir: File = context.cacheDir): Result` - `Luban.compress(input: File, outputDir: File): Result` - `Luban.compressToFile(input: File, output: File): Result` - `Luban.compress(context, inputs: List, outputDir: File = context.cacheDir): List>` - `Luban.compress(inputs: List, outputDir: File): List>` **Use in a custom CoroutineScope:** ```kotlin val scope = CoroutineScope(Dispatchers.Main + SupervisorJob()) scope.launch { val result = Luban.compress(context, inputUri) result.getOrElse { error -> // Handle error return@launch }.let { file -> // Handle success } } ``` ### ☕ Java / Builder Pattern For Java projects or if you prefer a callback-based approach, use the `Luban.with()` API which is compatible with the original library style. #### Compress a Single File ```java Luban.with(context) .load(imageFile) // Can be File, Uri, or String path .setTargetDir(context.getCacheDir()) .bindLifecycle(lifecycleOwner) // Optional: Auto-cancel on destroy .setCompressListener(new OnCompressListener() { @Override public void onStart() { // Compression started } @Override public void onSuccess(File file) { // Compression finished successfully } @Override public void onError(Throwable e) { // An error occurred } }) .launch(); ``` #### Compress Multiple Files ```java List imagePaths = ...; // List of image paths Luban.with(context) .load(imagePaths) // Load a list of images .setTargetDir(context.getCacheDir()) .setCompressListener(new OnCompressListener() { @Override public void onStart() { // Compression started } @Override public void onSuccess(File file) { // Called for EACH successfully compressed image Log.d("Luban", "Compressed: " + file.getAbsolutePath()); } @Override public void onError(Throwable e) { // An error occurred } }) .launch(); ``` # ☕ Donation If this project has been helpful to you, please consider supporting my work through the following methods. Your support is the motivation for me to continue improving and maintaining this project.
Alipay QR Code WeChat QR Code
Thank you for your support! 🙏 # 📄 License Copyright 2025 Zibin Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. ================================================ FILE: app/.gitignore ================================================ /build ================================================ FILE: app/build.gradle.kts ================================================ plugins { alias(libs.plugins.android.application) alias(libs.plugins.kotlin.android) alias(libs.plugins.kotlin.compose) } android { namespace = "top.zibin.luban.app" compileSdk { version = release(36) } defaultConfig { applicationId = "top.zibin.luban.app" minSdk = 26 targetSdk = 36 versionCode = 1 versionName = "1.0" testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner" } buildTypes { release { isMinifyEnabled = false proguardFiles( getDefaultProguardFile("proguard-android-optimize.txt"), "proguard-rules.pro" ) } } compileOptions { sourceCompatibility = JavaVersion.VERSION_17 targetCompatibility = JavaVersion.VERSION_17 } buildFeatures { compose = true } } dependencies { implementation(project(":luban")) implementation(libs.androidx.core.ktx) implementation(libs.androidx.lifecycle.runtime.ktx) implementation(libs.androidx.activity.compose) implementation(platform(libs.androidx.compose.bom)) implementation(libs.androidx.compose.ui) implementation(libs.androidx.compose.ui.graphics) implementation(libs.androidx.compose.ui.tooling.preview) implementation(libs.androidx.compose.material3) implementation(libs.androidx.compose.material.icons.extended) implementation(libs.coil.compose) testImplementation(libs.junit) androidTestImplementation(libs.androidx.junit) androidTestImplementation(libs.androidx.espresso.core) androidTestImplementation(platform(libs.androidx.compose.bom)) androidTestImplementation(libs.androidx.compose.ui.test.junit4) debugImplementation(libs.androidx.compose.ui.tooling) debugImplementation(libs.androidx.compose.ui.test.manifest) } ================================================ FILE: app/proguard-rules.pro ================================================ # Add project specific ProGuard rules here. # You can control the set of applied configuration files using the # proguardFiles setting in build.gradle. # # For more details, see # http://developer.android.com/guide/developing/tools/proguard.html # If your project uses WebView with JS, uncomment the following # and specify the fully qualified class name to the JavaScript interface # class: #-keepclassmembers class fqcn.of.javascript.interface.for.webview { # public *; #} # Uncomment this to preserve the line number information for # debugging stack traces. #-keepattributes SourceFile,LineNumberTable # If you keep the line number information, uncomment this to # hide the original source file name. #-renamesourcefileattribute SourceFile ================================================ FILE: app/src/androidTest/java/top/zibin/luban/app/ExampleInstrumentedTest.kt ================================================ package top.zibin.luban.app import androidx.test.platform.app.InstrumentationRegistry import androidx.test.ext.junit.runners.AndroidJUnit4 import org.junit.Test import org.junit.runner.RunWith import org.junit.Assert.* /** * Instrumented test, which will execute on an Android device. * * See [testing documentation](http://d.android.com/tools/testing). */ @RunWith(AndroidJUnit4::class) class ExampleInstrumentedTest { @Test fun useAppContext() { // Context of the app under test. val appContext = InstrumentationRegistry.getInstrumentation().targetContext assertEquals("top.zibin.luban.app", appContext.packageName) } } ================================================ FILE: app/src/main/AndroidManifest.xml ================================================ ================================================ FILE: app/src/main/java/top/zibin/luban/app/MainActivity.kt ================================================ package top.zibin.luban.app import android.os.Bundle import androidx.activity.ComponentActivity import androidx.activity.compose.rememberLauncherForActivityResult import androidx.activity.compose.setContent import androidx.activity.result.PickVisualMediaRequest import androidx.activity.result.contract.ActivityResultContracts import androidx.activity.viewModels import androidx.compose.foundation.BorderStroke import androidx.compose.foundation.background import androidx.compose.foundation.border import androidx.compose.foundation.clickable import androidx.compose.foundation.layout.Arrangement import androidx.compose.foundation.layout.Box import androidx.compose.foundation.layout.Column import androidx.compose.foundation.layout.PaddingValues import androidx.compose.foundation.layout.Row import androidx.compose.foundation.layout.Spacer import androidx.compose.foundation.layout.fillMaxSize import androidx.compose.foundation.layout.fillMaxWidth import androidx.compose.foundation.layout.height import androidx.compose.foundation.layout.padding import androidx.compose.foundation.layout.size import androidx.compose.foundation.layout.width import androidx.compose.foundation.rememberScrollState import androidx.compose.foundation.shape.RoundedCornerShape import androidx.compose.foundation.verticalScroll import androidx.compose.material.icons.Icons import androidx.compose.material.icons.filled.Close import androidx.compose.material.icons.filled.Compress import androidx.compose.material.icons.filled.Fullscreen import androidx.compose.material.icons.filled.Info import androidx.compose.material.icons.filled.PhotoLibrary import androidx.compose.material.icons.filled.PlayArrow import androidx.compose.material3.Button import androidx.compose.material3.Card import androidx.compose.material3.CardDefaults import androidx.compose.material3.CircularProgressIndicator import androidx.compose.material3.ExperimentalMaterial3Api import androidx.compose.material3.Icon import androidx.compose.material3.IconButton import androidx.compose.material3.MaterialTheme import androidx.compose.material3.OutlinedTextField import androidx.compose.material3.Scaffold import androidx.compose.material3.Text import androidx.compose.material3.TopAppBar import androidx.compose.runtime.mutableStateOf import androidx.compose.runtime.remember import androidx.compose.runtime.Composable import androidx.compose.runtime.LaunchedEffect import androidx.compose.runtime.collectAsState import androidx.compose.runtime.getValue import androidx.compose.ui.Alignment import androidx.compose.ui.Modifier import androidx.compose.ui.draw.clip import androidx.compose.ui.graphics.Color import androidx.compose.ui.layout.ContentScale import androidx.compose.ui.platform.LocalContext import androidx.compose.ui.text.font.FontWeight import androidx.compose.ui.unit.dp import androidx.compose.ui.window.Dialog import androidx.compose.ui.window.DialogProperties import coil.compose.AsyncImage import coil.request.ImageRequest class MainActivity : ComponentActivity() { private val viewModel: MainViewModel by viewModels() override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContent { MaterialTheme { MainScreen(viewModel) } } } } @OptIn(ExperimentalMaterial3Api::class) @Composable fun MainScreen(viewModel: MainViewModel) { val uiState by viewModel.uiState.collectAsState() val context = LocalContext.current LaunchedEffect(Unit) { viewModel.initStorageDirs(context) } val pickMedia = rememberLauncherForActivityResult(ActivityResultContracts.PickVisualMedia()) { uri -> if (uri != null) { viewModel.onImageSelected(context, uri) } } Scaffold( topBar = { TopAppBar( title = { Text("图片压缩示例") }, colors = androidx.compose.material3.TopAppBarDefaults.topAppBarColors( containerColor = MaterialTheme.colorScheme.primaryContainer, titleContentColor = MaterialTheme.colorScheme.onPrimaryContainer ) ) } ) { innerPadding -> Column( modifier = Modifier .fillMaxSize() .padding(innerPadding) .padding(16.dp) .verticalScroll(rememberScrollState()), verticalArrangement = Arrangement.spacedBy(16.dp) ) { if (uiState.appStorageDir != null) { Card( modifier = Modifier.fillMaxWidth(), colors = CardDefaults.cardColors( containerColor = MaterialTheme.colorScheme.secondaryContainer ), shape = RoundedCornerShape(8.dp) ) { Column( modifier = Modifier .fillMaxWidth() .padding(16.dp), verticalArrangement = Arrangement.spacedBy(12.dp) ) { Text( text = "批量压缩测试", style = MaterialTheme.typography.titleMedium, fontWeight = FontWeight.Bold ) Text( text = "输入目录: ${uiState.appStorageDir}", style = MaterialTheme.typography.bodySmall, color = Color.Gray ) Text( text = "输出目录: ${uiState.outputStorageDir}", style = MaterialTheme.typography.bodySmall, color = Color.Gray ) if (uiState.isBatchCompressing) { Row( modifier = Modifier.fillMaxWidth(), verticalAlignment = Alignment.CenterVertically, horizontalArrangement = Arrangement.spacedBy(12.dp) ) { CircularProgressIndicator( modifier = Modifier.size(24.dp), strokeWidth = 2.dp ) Text( text = "压缩中: ${uiState.batchProgress}/${uiState.batchTotal}", style = MaterialTheme.typography.bodyMedium ) } androidx.compose.material3.LinearProgressIndicator( progress = { if (uiState.batchTotal > 0) { uiState.batchProgress.toFloat() / uiState.batchTotal.toFloat() } else { 0f } }, modifier = Modifier.fillMaxWidth() ) } else { Button( onClick = { viewModel.batchCompressImages(context) }, modifier = Modifier.fillMaxWidth(), contentPadding = PaddingValues(vertical = 16.dp) ) { Icon( imageVector = Icons.Default.PlayArrow, contentDescription = null, modifier = Modifier.size(18.dp) ) Spacer(modifier = Modifier.width(8.dp)) Text("开始批量压缩") } } if (uiState.batchResult != null) { val result = uiState.batchResult!! Text( text = "压缩完成: 总计 ${result.total}, 成功 ${result.success}, 失败 ${result.failed}", style = MaterialTheme.typography.bodyMedium, fontWeight = FontWeight.Bold, color = if (result.failed == 0) Color(0xFF4CAF50) else Color(0xFFFF9800) ) if (result.outputDir != null) { Text( text = "输出目录: ${result.outputDir.absolutePath}", style = MaterialTheme.typography.bodySmall, color = Color.Gray ) } } } } } Button( onClick = { pickMedia.launch(PickVisualMediaRequest(ActivityResultContracts.PickVisualMedia.ImageOnly)) }, modifier = Modifier.fillMaxWidth(), contentPadding = PaddingValues(vertical = 16.dp) ) { Icon( imageVector = Icons.Default.PhotoLibrary, contentDescription = null, modifier = Modifier.size(18.dp) ) Spacer(modifier = Modifier.width(8.dp)) Text("从相册选择图片") } Button( onClick = { viewModel.compressImage(context) }, enabled = uiState.originalImage != null && !uiState.isCompressing, modifier = Modifier.fillMaxWidth(), contentPadding = PaddingValues(vertical = 16.dp) ) { if (uiState.isCompressing) { CircularProgressIndicator( modifier = Modifier.size(16.dp), strokeWidth = 2.dp, color = MaterialTheme.colorScheme.onPrimary ) Spacer(modifier = Modifier.width(8.dp)) Text("压缩中...") } else { Icon( imageVector = Icons.Default.Compress, contentDescription = null, modifier = Modifier.size(18.dp) ) Spacer(modifier = Modifier.width(8.dp)) Text("使用Luban算法压缩") } } if (uiState.error != null) { Text( text = uiState.error!!, color = MaterialTheme.colorScheme.error, modifier = Modifier.fillMaxWidth() ) } if (uiState.compressionTarget != null && uiState.originalImage != null) { CompressionTargetCard( originalWidth = uiState.originalImage!!.width, originalHeight = uiState.originalImage!!.height, target = uiState.compressionTarget!!, formatFileSize = viewModel::formatFileSize ) } if (uiState.originalImage != null) { ImagePreviewCard( title = "原图", imageInfo = uiState.originalImage!!, formatFileSize = viewModel::formatFileSize, onClick = { viewModel.openImageViewer(uiState.originalImage!!) } ) } if (uiState.compressedImage != null) { ImagePreviewCard( title = "压缩后", imageInfo = uiState.compressedImage!!, formatFileSize = viewModel::formatFileSize, onClick = { viewModel.openImageViewer(uiState.compressedImage!!) } ) } if (uiState.originalImage != null && uiState.compressedImage != null) { ComparisonCard( originalSize = uiState.originalImage!!.size, compressedSize = uiState.compressedImage!!.size, formatFileSize = viewModel::formatFileSize ) } } } if (uiState.showImageViewer && uiState.viewingImage != null) { FullScreenImageViewer( imageInfo = uiState.viewingImage!!, onClose = { viewModel.closeImageViewer() } ) } } @Composable fun CompressionTargetCard( originalWidth: Int, originalHeight: Int, target: top.zibin.luban.algorithm.CompressionTarget, formatFileSize: (Long) -> String ) { val blue50 = Color(0xFFE3F2FD) val blue200 = Color(0xFF90CAF9) val blue700 = Color(0xFF1976D2) Card( modifier = Modifier.fillMaxWidth(), colors = CardDefaults.cardColors( containerColor = blue50 ), border = BorderStroke(1.dp, blue200), shape = RoundedCornerShape(8.dp) ) { Column( modifier = Modifier .fillMaxWidth() .padding(12.dp), verticalArrangement = Arrangement.spacedBy(8.dp) ) { Row( verticalAlignment = Alignment.CenterVertically, horizontalArrangement = Arrangement.spacedBy(8.dp) ) { Icon( imageVector = Icons.Default.Info, contentDescription = null, tint = blue700, modifier = Modifier.size(20.dp) ) Text( text = "Luban压缩参数", style = MaterialTheme.typography.titleMedium, fontWeight = FontWeight.Bold, color = blue700 ) } InfoRow( label = "原图尺寸", value = "$originalWidth × $originalHeight" ) val sizeChanged = target.width != originalWidth || target.height != originalHeight InfoRow( label = "目标尺寸", value = "${target.width} × ${target.height}", highlight = sizeChanged ) InfoRow( label = "压缩质量", value = "60%" ) InfoRow( label = "预计大小", value = formatFileSize(target.estimatedSizeKb * 1024L) ) } } } @Composable fun InfoRow( label: String, value: String, highlight: Boolean = false ) { Row( modifier = Modifier.fillMaxWidth(), horizontalArrangement = Arrangement.SpaceBetween ) { Text( text = label, style = MaterialTheme.typography.bodyMedium, color = Color.Gray.copy(alpha = 0.7f) ) Text( text = value, style = MaterialTheme.typography.bodyMedium, fontWeight = if (highlight) FontWeight.Bold else FontWeight.Normal, color = if (highlight) Color(0xFF1976D2) else Color.Black.copy(alpha = 0.87f) ) } } @Composable fun ImagePreviewCard( title: String, imageInfo: ImageInfo, formatFileSize: (Long) -> String, onClick: () -> Unit ) { Column( modifier = Modifier.fillMaxWidth(), verticalArrangement = Arrangement.spacedBy(8.dp) ) { Text( text = title, style = MaterialTheme.typography.titleMedium, fontWeight = FontWeight.Bold ) Box( modifier = Modifier .fillMaxWidth() .height(200.dp) .clip(RoundedCornerShape(8.dp)) .border(1.dp, Color.Gray, RoundedCornerShape(8.dp)) .clickable(onClick = onClick) ) { val model = imageInfo.file ?: imageInfo.uri AsyncImage( model = ImageRequest.Builder(LocalContext.current) .data(model) .crossfade(true) .build(), contentDescription = title, modifier = Modifier.fillMaxSize(), contentScale = ContentScale.Fit ) Box( modifier = Modifier .align(Alignment.TopEnd) .padding(8.dp) .background( Color.Black.copy(alpha = 0.5f), RoundedCornerShape(20.dp) ) .padding(6.dp) ) { Icon( imageVector = Icons.Default.Fullscreen, contentDescription = "全屏查看", tint = Color.White, modifier = Modifier.size(18.dp) ) } } Text( text = "大小: ${formatFileSize(imageInfo.size)}", style = MaterialTheme.typography.bodySmall, color = Color.Gray ) Text( text = "尺寸: ${imageInfo.width} × ${imageInfo.height}", style = MaterialTheme.typography.bodySmall, color = Color.Gray ) } } @Composable fun ComparisonCard( originalSize: Long, compressedSize: Long, formatFileSize: (Long) -> String ) { val blue50 = Color(0xFFE3F2FD) val compressionRatio = compressedSize.toFloat() / originalSize.toFloat() val savedSize = originalSize - compressedSize val ratioPercent = (1 - compressionRatio) * 100 val color = when { ratioPercent > 50 -> Color(0xFF4CAF50) ratioPercent > 20 -> Color(0xFF2196F3) else -> Color(0xFFFF9800) } Card( modifier = Modifier.fillMaxWidth(), colors = CardDefaults.cardColors( containerColor = blue50 ), shape = RoundedCornerShape(8.dp) ) { Column( modifier = Modifier .fillMaxWidth() .padding(16.dp), verticalArrangement = Arrangement.spacedBy(12.dp) ) { Text( text = "压缩对比", style = MaterialTheme.typography.titleLarge, fontWeight = FontWeight.Bold ) ComparisonRow( label = "文件大小", original = formatFileSize(originalSize), compressed = formatFileSize(compressedSize), color = color ) ComparisonRow( label = "压缩率", original = "100%", compressed = "${(compressionRatio * 100).toString().take(4)}%", color = color ) ComparisonRow( label = "节省空间", original = "-", compressed = formatFileSize(savedSize), color = color ) } } } @Composable fun ComparisonRow( label: String, original: String, compressed: String, color: Color ) { Row( modifier = Modifier.fillMaxWidth(), horizontalArrangement = Arrangement.SpaceBetween, verticalAlignment = Alignment.CenterVertically ) { Text( text = label, style = MaterialTheme.typography.bodyMedium, fontWeight = FontWeight.Medium ) Row( verticalAlignment = Alignment.CenterVertically, horizontalArrangement = Arrangement.spacedBy(8.dp) ) { Text( text = original, style = MaterialTheme.typography.bodyMedium, color = Color.Gray ) Text("→", color = Color.Gray) Text( text = compressed, style = MaterialTheme.typography.bodyMedium, fontWeight = FontWeight.Bold, color = color ) } } } @Composable fun FullScreenImageViewer( imageInfo: ImageInfo, onClose: () -> Unit ) { Dialog( onDismissRequest = onClose, properties = DialogProperties( usePlatformDefaultWidth = false, decorFitsSystemWindows = false ) ) { Box( modifier = Modifier .fillMaxSize() .background(Color.Black) ) { val model = imageInfo.file ?: imageInfo.uri AsyncImage( model = ImageRequest.Builder(LocalContext.current) .data(model) .crossfade(true) .build(), contentDescription = "全屏图片", modifier = Modifier.fillMaxSize(), contentScale = ContentScale.Fit ) IconButton( onClick = onClose, modifier = Modifier .align(Alignment.TopEnd) .padding(16.dp) ) { Icon( imageVector = Icons.Default.Close, contentDescription = "关闭", tint = Color.White ) } } } } ================================================ FILE: app/src/main/java/top/zibin/luban/app/MainViewModel.kt ================================================ package top.zibin.luban.app import android.content.Context import android.graphics.BitmapFactory import android.net.Uri import android.util.Log import androidx.lifecycle.ViewModel import androidx.lifecycle.viewModelScope import kotlinx.coroutines.Dispatchers import kotlinx.coroutines.flow.MutableStateFlow import kotlinx.coroutines.flow.StateFlow import kotlinx.coroutines.flow.asStateFlow import kotlinx.coroutines.flow.update import kotlinx.coroutines.launch import top.zibin.luban.api.Luban import top.zibin.luban.api.luban import top.zibin.luban.algorithm.CompressionCalculator import top.zibin.luban.algorithm.CompressionTarget import java.io.File import java.io.FileOutputStream import java.io.InputStream import java.util.Locale data class ImageInfo( val uri: Uri? = null, val file: File? = null, val size: Long = 0, val width: Int = 0, val height: Int = 0 ) data class BatchCompressResult( val total: Int, val success: Int, val failed: Int, val outputDir: File? ) data class MainUiState( val originalImage: ImageInfo? = null, val compressedImage: ImageInfo? = null, val compressionTarget: CompressionTarget? = null, val isCompressing: Boolean = false, val error: String? = null, val showImageViewer: Boolean = false, val viewingImage: ImageInfo? = null, val isBatchCompressing: Boolean = false, val batchProgress: Int = 0, val batchTotal: Int = 0, val batchResult: BatchCompressResult? = null, val appStorageDir: String? = null, val outputStorageDir: String? = null ) class MainViewModel : ViewModel() { private val _uiState = MutableStateFlow(MainUiState()) val uiState: StateFlow = _uiState.asStateFlow() private val calculator = CompressionCalculator() fun onImageSelected(context: Context, uri: Uri) { viewModelScope.launch(Dispatchers.IO) { try { val fileSize = context.contentResolver.openFileDescriptor(uri, "r")?.statSize ?: 0 val options = android.graphics.BitmapFactory.Options().apply { inJustDecodeBounds = true } context.contentResolver.openInputStream(uri)?.use { android.graphics.BitmapFactory.decodeStream(it, null, options) } val target = calculator.calculateTarget(options.outWidth, options.outHeight) _uiState.update { it.copy( originalImage = ImageInfo( uri = uri, size = fileSize, width = options.outWidth, height = options.outHeight ), compressedImage = null, compressionTarget = target, error = null ) } } catch (e: Exception) { _uiState.update { it.copy(error = "选择图片失败: ${e.message}") } } } } fun compressImage(context: Context) { val originalUri = _uiState.value.originalImage?.uri ?: return viewModelScope.launch(Dispatchers.IO) { _uiState.update { it.copy(isCompressing = true, error = null) } val outputDir = File(context.cacheDir, "luban_compressed") if (!outputDir.exists()) { outputDir.mkdirs() } val results = luban(context) { this.outputDir = outputDir compress(originalUri) } val result = results.firstOrNull() ?: Result.failure(IllegalStateException("No compression result")) result.getOrElse { error -> _uiState.update { it.copy(isCompressing = false, error = "压缩失败: ${error.message}") } return@launch }.let { file -> val options = BitmapFactory.Options().apply { inJustDecodeBounds = true } BitmapFactory.decodeFile(file.absolutePath, options) _uiState.update { it.copy( isCompressing = false, compressedImage = ImageInfo( file = file, size = file.length(), width = options.outWidth, height = options.outHeight ) ) } } } } fun openImageViewer(imageInfo: ImageInfo) { _uiState.update { it.copy(showImageViewer = true, viewingImage = imageInfo) } } fun closeImageViewer() { _uiState.update { it.copy(showImageViewer = false, viewingImage = null) } } fun initStorageDirs(context: Context) { viewModelScope.launch(Dispatchers.IO) { val appStorageDir = getAppStorageDir(context) val outputStorageDir = getOutputStorageDir(context) appStorageDir?.let { dir -> copyAssetsToStorage(context, dir) } _uiState.update { it.copy( appStorageDir = appStorageDir?.absolutePath, outputStorageDir = outputStorageDir?.absolutePath ) } } } private fun copyAssetsToStorage(context: Context, targetDir: File) { try { val assetManager = context.assets val assetFiles = assetManager.list("test_images") ?: emptyArray() if (assetFiles.isEmpty()) { Log.d("AssetCopy", "assets/test_images 目录为空,跳过复制") return } val imageExtensions = setOf(".jpg", ".jpeg", ".png", ".webp", ".bmp") assetFiles.forEach { fileName -> val lowerFileName = fileName.lowercase() val isImageFile = imageExtensions.any { lowerFileName.endsWith(it) } if (!isImageFile) { Log.d("AssetCopy", "跳过非图片文件: $fileName") return@forEach } val targetFile = File(targetDir, fileName) if (targetFile.exists()) { Log.d("AssetCopy", "文件已存在,跳过: $fileName") return@forEach } try { assetManager.open("test_images/$fileName").use { input -> FileOutputStream(targetFile).use { output -> input.copyTo(output) } } Log.d("AssetCopy", "复制成功: $fileName") } catch (e: Exception) { Log.e("AssetCopy", "复制失败: $fileName", e) } } } catch (e: Exception) { Log.e("AssetCopy", "复制assets图片失败", e) } } private fun getAppStorageDir(context: Context): File? { val externalFilesDir = context.getExternalFilesDir(null)?.parentFile return externalFilesDir?.let { val appDir = File(it, "images") if (!appDir.exists()) { appDir.mkdirs() } appDir } } private fun getOutputStorageDir(context: Context): File? { val externalFilesDir = context.getExternalFilesDir(null)?.parentFile return externalFilesDir?.let { val outputDir = File(it, "compressed") if (!outputDir.exists()) { outputDir.mkdirs() } outputDir } } fun batchCompressImages(context: Context) { viewModelScope.launch(Dispatchers.IO) { val inputDir = getAppStorageDir(context) val outputDir = getOutputStorageDir(context) if (inputDir == null || outputDir == null) { _uiState.update { it.copy(error = "无法访问存储目录,请检查权限") } return@launch } if (!inputDir.exists()) { _uiState.update { it.copy(error = "输入目录不存在: ${inputDir.absolutePath}") } return@launch } val imageFiles = inputDir.listFiles { file -> file.isFile && (file.name.endsWith(".jpg", ignoreCase = true) || file.name.endsWith(".jpeg", ignoreCase = true) || file.name.endsWith(".png", ignoreCase = true)) } ?: emptyArray() if (imageFiles.isEmpty()) { _uiState.update { it.copy(error = "输入目录中没有找到图片文件: ${inputDir.absolutePath}") } return@launch } _uiState.update { it.copy( isBatchCompressing = true, batchProgress = 0, batchTotal = imageFiles.size, batchResult = null, error = null ) } val inputList = imageFiles.toList() Log.d("BatchCompress", "开始批量压缩,共 ${inputList.size} 张图片") val results = luban(context) { this.outputDir = outputDir compress(inputList) } var successCount = 0 var failedCount = 0 results.forEachIndexed { index, result -> val inputFile = inputList[index] result.getOrNull()?.let { compressedFile -> successCount++ val options = BitmapFactory.Options().apply { inJustDecodeBounds = true } BitmapFactory.decodeFile(compressedFile.absolutePath, options) val width = options.outWidth val height = options.outHeight val fileSize = compressedFile.length() val fileSizeKB = fileSize / 1024.0 val fileSizeMB = fileSizeKB / 1024.0 val sizeStr = when { fileSizeMB >= 1.0 -> String.format("%.2f MB", fileSizeMB) else -> String.format("%.2f KB", fileSizeKB) } Log.d( "BatchCompress", "[${index + 1}/${inputList.size}] 压缩成功: " + "文件名=${compressedFile.name}, " + "分辨率=${width}×${height}, " + "文件大小=${sizeStr} (${fileSize} bytes)" ) } ?: run { failedCount++ val error = result.exceptionOrNull() Log.e( "BatchCompress", "[${index + 1}/${inputList.size}] 压缩失败: ${inputFile.name}, 错误=${error?.message}" ) } _uiState.update { it.copy(batchProgress = index + 1) } } Log.d( "BatchCompress", "批量压缩完成: 总计=${inputList.size}, 成功=${successCount}, 失败=${failedCount}" ) _uiState.update { it.copy( isBatchCompressing = false, batchResult = BatchCompressResult( total = inputList.size, success = successCount, failed = failedCount, outputDir = outputDir ) ) } } } fun formatFileSize(size: Long): String { if (size <= 0) return "0 B" val units = arrayOf("B", "KB", "MB", "GB", "TB") val digitGroups = (Math.log10(size.toDouble()) / Math.log10(1024.0)).toInt() return String.format( Locale.US, "%.2f %s", size / Math.pow(1024.0, digitGroups.toDouble()), units[digitGroups] ) } } ================================================ FILE: app/src/main/java/top/zibin/luban/app/ui/theme/Color.kt ================================================ package top.zibin.luban.app.ui.theme import androidx.compose.ui.graphics.Color val Purple80 = Color(0xFFD0BCFF) val PurpleGrey80 = Color(0xFFCCC2DC) val Pink80 = Color(0xFFEFB8C8) val Purple40 = Color(0xFF6650a4) val PurpleGrey40 = Color(0xFF625b71) val Pink40 = Color(0xFF7D5260) ================================================ FILE: app/src/main/java/top/zibin/luban/app/ui/theme/Theme.kt ================================================ package top.zibin.luban.app.ui.theme import android.app.Activity import android.os.Build import androidx.compose.foundation.isSystemInDarkTheme import androidx.compose.material3.MaterialTheme import androidx.compose.material3.darkColorScheme import androidx.compose.material3.dynamicDarkColorScheme import androidx.compose.material3.dynamicLightColorScheme import androidx.compose.material3.lightColorScheme import androidx.compose.runtime.Composable import androidx.compose.ui.platform.LocalContext private val DarkColorScheme = darkColorScheme( primary = Purple80, secondary = PurpleGrey80, tertiary = Pink80 ) private val LightColorScheme = lightColorScheme( primary = Purple40, secondary = PurpleGrey40, tertiary = Pink40 /* Other default colors to override background = Color(0xFFFFFBFE), surface = Color(0xFFFFFBFE), onPrimary = Color.White, onSecondary = Color.White, onTertiary = Color.White, onBackground = Color(0xFF1C1B1F), onSurface = Color(0xFF1C1B1F), */ ) @Composable fun KotlinLubanTheme( darkTheme: Boolean = isSystemInDarkTheme(), // Dynamic color is available on Android 12+ dynamicColor: Boolean = true, content: @Composable () -> Unit ) { val colorScheme = when { dynamicColor && Build.VERSION.SDK_INT >= Build.VERSION_CODES.S -> { val context = LocalContext.current if (darkTheme) dynamicDarkColorScheme(context) else dynamicLightColorScheme(context) } darkTheme -> DarkColorScheme else -> LightColorScheme } MaterialTheme( colorScheme = colorScheme, typography = Typography, content = content ) } ================================================ FILE: app/src/main/java/top/zibin/luban/app/ui/theme/Type.kt ================================================ package top.zibin.luban.app.ui.theme import androidx.compose.material3.Typography import androidx.compose.ui.text.TextStyle import androidx.compose.ui.text.font.FontFamily import androidx.compose.ui.text.font.FontWeight import androidx.compose.ui.unit.sp // Set of Material typography styles to start with val Typography = Typography( bodyLarge = TextStyle( fontFamily = FontFamily.Default, fontWeight = FontWeight.Normal, fontSize = 16.sp, lineHeight = 24.sp, letterSpacing = 0.5.sp ) /* Other default text styles to override titleLarge = TextStyle( fontFamily = FontFamily.Default, fontWeight = FontWeight.Normal, fontSize = 22.sp, lineHeight = 28.sp, letterSpacing = 0.sp ), labelSmall = TextStyle( fontFamily = FontFamily.Default, fontWeight = FontWeight.Medium, fontSize = 11.sp, lineHeight = 16.sp, letterSpacing = 0.5.sp ) */ ) ================================================ FILE: app/src/main/res/drawable/ic_launcher_background.xml ================================================ ================================================ FILE: app/src/main/res/drawable/ic_launcher_foreground.xml ================================================ ================================================ FILE: app/src/main/res/mipmap-anydpi/ic_launcher.xml ================================================ ================================================ FILE: app/src/main/res/mipmap-anydpi/ic_launcher_round.xml ================================================ ================================================ FILE: app/src/main/res/values/colors.xml ================================================ #FFBB86FC #FF6200EE #FF3700B3 #FF03DAC5 #FF018786 #FF000000 #FFFFFFFF ================================================ FILE: app/src/main/res/values/strings.xml ================================================ Kotlin Luban ================================================ FILE: app/src/main/res/values/themes.xml ================================================ ================================================ FILE: app-java/src/main/res/values-night/themes.xml ================================================ ================================================ FILE: app-java/src/main/res/xml/backup_rules.xml ================================================ ================================================ FILE: app-java/src/main/res/xml/data_extraction_rules.xml ================================================ ================================================ FILE: app-java/src/test/java/top/zibin/luban/app/java/ExampleUnitTest.java ================================================ package top.zibin.luban.app.java; import org.junit.Test; import static org.junit.Assert.*; /** * Example local unit test, which will execute on the development machine (host). * * @see Testing documentation */ public class ExampleUnitTest { @Test public void addition_isCorrect() { assertEquals(4, 2 + 2); } } ================================================ FILE: build.gradle.kts ================================================ plugins { alias(libs.plugins.android.application) apply false alias(libs.plugins.kotlin.android) apply false alias(libs.plugins.kotlin.compose) apply false alias(libs.plugins.android.library) apply false alias(libs.plugins.maven.publish) apply false } ================================================ FILE: gradle/libs.versions.toml ================================================ [versions] agp = "9.0.0" kotlin = "2.3.0" coreKtx = "1.17.0" junit = "4.13.2" junitVersion = "1.3.0" espressoCore = "3.7.0" lifecycleRuntimeKtx = "2.10.0" activityCompose = "1.12.2" composeBom = "2025.12.01" coroutines = "1.10.2" exifinterface = "1.4.2" appcompat = "1.7.1" material = "1.13.0" coil = "2.7.0" mavenPublish = "0.35.0" [libraries] androidx-core-ktx = { group = "androidx.core", name = "core-ktx", version.ref = "coreKtx" } junit = { group = "junit", name = "junit", version.ref = "junit" } androidx-junit = { group = "androidx.test.ext", name = "junit", version.ref = "junitVersion" } androidx-espresso-core = { group = "androidx.test.espresso", name = "espresso-core", version.ref = "espressoCore" } androidx-lifecycle-runtime-ktx = { group = "androidx.lifecycle", name = "lifecycle-runtime-ktx", version.ref = "lifecycleRuntimeKtx" } androidx-activity-compose = { group = "androidx.activity", name = "activity-compose", version.ref = "activityCompose" } androidx-compose-bom = { group = "androidx.compose", name = "compose-bom", version.ref = "composeBom" } androidx-compose-ui = { group = "androidx.compose.ui", name = "ui" } androidx-compose-ui-graphics = { group = "androidx.compose.ui", name = "ui-graphics" } androidx-compose-ui-tooling = { group = "androidx.compose.ui", name = "ui-tooling" } androidx-compose-ui-tooling-preview = { group = "androidx.compose.ui", name = "ui-tooling-preview" } androidx-compose-ui-test-manifest = { group = "androidx.compose.ui", name = "ui-test-manifest" } androidx-compose-ui-test-junit4 = { group = "androidx.compose.ui", name = "ui-test-junit4" } androidx-compose-material3 = { group = "androidx.compose.material3", name = "material3" } androidx-compose-material-icons-extended = { group = "androidx.compose.material", name = "material-icons-extended" } androidx-appcompat = { group = "androidx.appcompat", name = "appcompat", version.ref = "appcompat" } material = { group = "com.google.android.material", name = "material", version.ref = "material" } kotlinx-coroutines-android = { group = "org.jetbrains.kotlinx", name = "kotlinx-coroutines-android", version.ref = "coroutines" } kotlinx-coroutines-core = { group = "org.jetbrains.kotlinx", name = "kotlinx-coroutines-core", version.ref = "coroutines" } androidx-exifinterface = { group = "androidx.exifinterface", name = "exifinterface", version.ref = "exifinterface" } coil-compose = { group = "io.coil-kt", name = "coil-compose", version.ref = "coil" } [plugins] android-application = { id = "com.android.application", version.ref = "agp" } kotlin-android = { id = "org.jetbrains.kotlin.android", version.ref = "kotlin" } kotlin-compose = { id = "org.jetbrains.kotlin.plugin.compose", version.ref = "kotlin" } android-library = { id = "com.android.library", version.ref = "agp" } maven-publish = { id = "com.vanniktech.maven.publish", version.ref = "mavenPublish" } ================================================ FILE: gradle/wrapper/gradle-wrapper.properties ================================================ #Mon Jan 05 11:56:32 CST 2026 distributionBase=GRADLE_USER_HOME distributionPath=wrapper/dists distributionUrl=https\://services.gradle.org/distributions/gradle-9.3.0-bin.zip networkTimeout=10000 validateDistributionUrl=true zipStoreBase=GRADLE_USER_HOME zipStorePath=wrapper/dists ================================================ FILE: gradle.properties ================================================ # Project-wide Gradle settings. # IDE (e.g. Android Studio) users: # Gradle settings configured through the IDE *will override* # any settings specified in this file. # For more details on how to configure your build environment visit # http://www.gradle.org/docs/current/userguide/build_environment.html # Specifies the JVM arguments used for the daemon process. # The setting is particularly useful for tweaking memory settings. org.gradle.jvmargs=-Xmx2048m -Dfile.encoding=UTF-8 # When configured, Gradle will run in incubating parallel mode. # This option should only be used with decoupled projects. For more details, visit # https://developer.android.com/r/tools/gradle-multi-project-decoupled-projects # org.gradle.parallel=true # AndroidX package structure to make it clearer which packages are bundled with the # Android operating system, and which are packaged with your app's APK # https://developer.android.com/topic/libraries/support-library/androidx-rn android.useAndroidX=true # Kotlin code style for this project: "official" or "obsolete": kotlin.code.style=official # Enables namespacing of each library's R class so that its R class includes only the # resources declared in the library itself and none from the library's dependencies, # thereby reducing the size of the R class for that library android.nonTransitiveRClass=true android.defaults.buildfeatures.resvalues=true android.sdk.defaultTargetSdkToCompileSdkIfUnset=false android.enableAppCompileTimeRClass=false android.usesSdkInManifest.disallowed=false android.uniquePackageNames=false android.dependency.useConstraints=true android.r8.strictFullModeForKeepRules=false android.r8.optimizedResourceShrinking=false android.builtInKotlin=false android.newDsl=false ================================================ FILE: gradlew ================================================ #!/bin/sh # # Copyright © 2015 the original authors. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # https://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. # # SPDX-License-Identifier: Apache-2.0 # ############################################################################## # # Gradle start up script for POSIX generated by Gradle. # # Important for running: # # (1) You need a POSIX-compliant shell to run this script. If your /bin/sh is # noncompliant, but you have some other compliant shell such as ksh or # bash, then to run this script, type that shell name before the whole # command line, like: # # ksh Gradle # # Busybox and similar reduced shells will NOT work, because this script # requires all of these POSIX shell features: # * functions; # * expansions «$var», «${var}», «${var:-default}», «${var+SET}», # «${var#prefix}», «${var%suffix}», and «$( cmd )»; # * compound commands having a testable exit status, especially «case»; # * various built-in commands including «command», «set», and «ulimit». # # Important for patching: # # (2) This script targets any POSIX shell, so it avoids extensions provided # by Bash, Ksh, etc; in particular arrays are avoided. # # The "traditional" practice of packing multiple parameters into a # space-separated string is a well documented source of bugs and security # problems, so this is (mostly) avoided, by progressively accumulating # options in "$@", and eventually passing that to Java. # # Where the inherited environment variables (DEFAULT_JVM_OPTS, JAVA_OPTS, # and GRADLE_OPTS) rely on word-splitting, this is performed explicitly; # see the in-line comments for details. # # There are tweaks for specific operating systems such as AIX, CygWin, # Darwin, MinGW, and NonStop. # # (3) This script is generated from the Groovy template # https://github.com/gradle/gradle/blob/HEAD/platforms/jvm/plugins-application/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt # within the Gradle project. # # You can find Gradle at https://github.com/gradle/gradle/. # ############################################################################## # Attempt to set APP_HOME # Resolve links: $0 may be a link app_path=$0 # Need this for daisy-chained symlinks. while APP_HOME=${app_path%"${app_path##*/}"} # leaves a trailing /; empty if no leading path [ -h "$app_path" ] do ls=$( ls -ld "$app_path" ) link=${ls#*' -> '} case $link in #( /*) app_path=$link ;; #( *) app_path=$APP_HOME$link ;; esac done # This is normally unused # shellcheck disable=SC2034 APP_BASE_NAME=${0##*/} # Discard cd standard output in case $CDPATH is set (https://github.com/gradle/gradle/issues/25036) APP_HOME=$( cd -P "${APP_HOME:-./}" > /dev/null && printf '%s\n' "$PWD" ) || exit # Use the maximum available, or set MAX_FD != -1 to use that value. MAX_FD=maximum warn () { echo "$*" } >&2 die () { echo echo "$*" echo exit 1 } >&2 # OS specific support (must be 'true' or 'false'). cygwin=false msys=false darwin=false nonstop=false case "$( uname )" in #( CYGWIN* ) cygwin=true ;; #( Darwin* ) darwin=true ;; #( MSYS* | MINGW* ) msys=true ;; #( NONSTOP* ) nonstop=true ;; esac CLASSPATH="\\\"\\\"" # Determine the Java command to use to start the JVM. if [ -n "$JAVA_HOME" ] ; then if [ -x "$JAVA_HOME/jre/sh/java" ] ; then # IBM's JDK on AIX uses strange locations for the executables JAVACMD=$JAVA_HOME/jre/sh/java else JAVACMD=$JAVA_HOME/bin/java fi if [ ! -x "$JAVACMD" ] ; then die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME Please set the JAVA_HOME variable in your environment to match the location of your Java installation." fi else JAVACMD=java if ! command -v java >/dev/null 2>&1 then die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. Please set the JAVA_HOME variable in your environment to match the location of your Java installation." fi fi # Increase the maximum file descriptors if we can. if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then case $MAX_FD in #( max*) # In POSIX sh, ulimit -H is undefined. That's why the result is checked to see if it worked. # shellcheck disable=SC2039,SC3045 MAX_FD=$( ulimit -H -n ) || warn "Could not query maximum file descriptor limit" esac case $MAX_FD in #( '' | soft) :;; #( *) # In POSIX sh, ulimit -n is undefined. That's why the result is checked to see if it worked. # shellcheck disable=SC2039,SC3045 ulimit -n "$MAX_FD" || warn "Could not set maximum file descriptor limit to $MAX_FD" esac fi # Collect all arguments for the java command, stacking in reverse order: # * args from the command line # * the main class name # * -classpath # * -D...appname settings # * --module-path (only if needed) # * DEFAULT_JVM_OPTS, JAVA_OPTS, and GRADLE_OPTS environment variables. # For Cygwin or MSYS, switch paths to Windows format before running java if "$cygwin" || "$msys" ; then APP_HOME=$( cygpath --path --mixed "$APP_HOME" ) CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" ) JAVACMD=$( cygpath --unix "$JAVACMD" ) # Now convert the arguments - kludge to limit ourselves to /bin/sh for arg do if case $arg in #( -*) false ;; # don't mess with options #( /?*) t=${arg#/} t=/${t%%/*} # looks like a POSIX filepath [ -e "$t" ] ;; #( *) false ;; esac then arg=$( cygpath --path --ignore --mixed "$arg" ) fi # Roll the args list around exactly as many times as the number of # args, so each arg winds up back in the position where it started, but # possibly modified. # # NB: a `for` loop captures its iteration list before it begins, so # changing the positional parameters here affects neither the number of # iterations, nor the values presented in `arg`. shift # remove old arg set -- "$@" "$arg" # push replacement arg done fi # Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script. DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"' # Collect all arguments for the java command: # * DEFAULT_JVM_OPTS, JAVA_OPTS, and optsEnvironmentVar are not allowed to contain shell fragments, # and any embedded shellness will be escaped. # * For example: A user cannot expect ${Hostname} to be expanded, as it is an environment variable and will be # treated as '${Hostname}' itself on the command line. set -- \ "-Dorg.gradle.appname=$APP_BASE_NAME" \ -classpath "$CLASSPATH" \ -jar "$APP_HOME/gradle/wrapper/gradle-wrapper.jar" \ "$@" # Stop when "xargs" is not available. if ! command -v xargs >/dev/null 2>&1 then die "xargs is not available" fi # Use "xargs" to parse quoted args. # # With -n1 it outputs one arg per line, with the quotes and backslashes removed. # # In Bash we could simply go: # # readarray ARGS < <( xargs -n1 <<<"$var" ) && # set -- "${ARGS[@]}" "$@" # # but POSIX shell has neither arrays nor command substitution, so instead we # post-process each arg (as a line of input to sed) to backslash-escape any # character that might be a shell metacharacter, then use eval to reverse # that process (while maintaining the separation between arguments), and wrap # the whole thing up as a single "set" statement. # # This will of course break if any of these variables contains a newline or # an unmatched quote. # eval "set -- $( printf '%s\n' "$DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS" | xargs -n1 | sed ' s~[^-[:alnum:]+,./:=@_]~\\&~g; ' | tr '\n' ' ' )" '"$@"' exec "$JAVACMD" "$@" ================================================ FILE: gradlew.bat ================================================ @rem @rem Copyright 2015 the original author or authors. @rem @rem Licensed under the Apache License, Version 2.0 (the "License"); @rem you may not use this file except in compliance with the License. @rem You may obtain a copy of the License at @rem @rem https://www.apache.org/licenses/LICENSE-2.0 @rem @rem Unless required by applicable law or agreed to in writing, software @rem distributed under the License is distributed on an "AS IS" BASIS, @rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. @rem See the License for the specific language governing permissions and @rem limitations under the License. @rem @rem SPDX-License-Identifier: Apache-2.0 @rem @if "%DEBUG%"=="" @echo off @rem ########################################################################## @rem @rem Gradle startup script for Windows @rem @rem ########################################################################## @rem Set local scope for the variables with windows NT shell if "%OS%"=="Windows_NT" setlocal set DIRNAME=%~dp0 if "%DIRNAME%"=="" set DIRNAME=. @rem This is normally unused set APP_BASE_NAME=%~n0 set APP_HOME=%DIRNAME% @rem Resolve any "." and ".." in APP_HOME to make it shorter. for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi @rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script. set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m" @rem Find java.exe if defined JAVA_HOME goto findJavaFromJavaHome set JAVA_EXE=java.exe %JAVA_EXE% -version >NUL 2>&1 if %ERRORLEVEL% equ 0 goto execute echo. 1>&2 echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. 1>&2 echo. 1>&2 echo Please set the JAVA_HOME variable in your environment to match the 1>&2 echo location of your Java installation. 1>&2 goto fail :findJavaFromJavaHome set JAVA_HOME=%JAVA_HOME:"=% set JAVA_EXE=%JAVA_HOME%/bin/java.exe if exist "%JAVA_EXE%" goto execute echo. 1>&2 echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME% 1>&2 echo. 1>&2 echo Please set the JAVA_HOME variable in your environment to match the 1>&2 echo location of your Java installation. 1>&2 goto fail :execute @rem Setup the command line set CLASSPATH= @rem Execute Gradle "%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" -jar "%APP_HOME%\gradle\wrapper\gradle-wrapper.jar" %* :end @rem End local scope for the variables with windows NT shell if %ERRORLEVEL% equ 0 goto mainEnd :fail rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of rem the _cmd.exe /c_ return code! set EXIT_CODE=%ERRORLEVEL% if %EXIT_CODE% equ 0 set EXIT_CODE=1 if not ""=="%GRADLE_EXIT_CONSOLE%" exit %EXIT_CODE% exit /b %EXIT_CODE% :mainEnd if "%OS%"=="Windows_NT" endlocal :omega ================================================ FILE: luban/.gitignore ================================================ /build ================================================ FILE: luban/build.gradle.kts ================================================ @file:Suppress("UnstableApiUsage") plugins { alias(libs.plugins.android.library) alias(libs.plugins.kotlin.android) alias(libs.plugins.maven.publish) } val libraryVersion = "2.0.1" android { namespace = "top.zibin.luban" compileSdk = 36 defaultConfig { minSdk = 21 testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner" consumerProguardFiles("consumer-rules.pro") ndk { abiFilters += listOf("armeabi-v7a", "arm64-v8a", "x86", "x86_64") } externalNativeBuild { cmake { cppFlags += "-std=c++17" arguments += listOf("-DANDROID_STL=c++_static", "-DANDROID_SUPPORT_FLEXIBLE_PAGE_SIZES=ON") } } } buildTypes { release { isMinifyEnabled = false proguardFiles( getDefaultProguardFile("proguard-android-optimize.txt"), "proguard-rules.pro" ) } } compileOptions { sourceCompatibility = JavaVersion.VERSION_17 targetCompatibility = JavaVersion.VERSION_17 } kotlin { compilerOptions { jvmTarget.set(org.jetbrains.kotlin.gradle.dsl.JvmTarget.JVM_17) } } externalNativeBuild { cmake { path = file("src/main/cpp/CMakeLists.txt") version = "3.22.1" } } packaging { jniLibs { useLegacyPackaging = true excludes += "lib/**/libc++_shared.so" } } } dependencies { api(libs.kotlinx.coroutines.android) api(libs.kotlinx.coroutines.core) implementation(libs.androidx.core.ktx) implementation(libs.androidx.appcompat) implementation(libs.material) implementation(libs.androidx.exifinterface) testImplementation(libs.junit) androidTestImplementation(libs.androidx.junit) androidTestImplementation(libs.androidx.espresso.core) } mavenPublishing { publishToMavenCentral() signAllPublications() coordinates("top.zibin", "luban", libraryVersion) pom { name.set("Luban") description.set("Luban(鲁班) —— Android图片压缩工具,仿微信朋友圈压缩策略。") url.set("https://github.com/Curzibn/Luban") licenses { license { name.set("The Apache License, Version 2.0") url.set("http://www.apache.org/licenses/LICENSE-2.0.txt") distribution.set("http://www.apache.org/licenses/LICENSE-2.0.txt") } } developers { developer { id.set("Curzibn") name.set("Zibin Zheng") email.set("a@zibin.top") } } scm { connection.set("scm:git:git://github.com/Curzibn/Luban.git") developerConnection.set("scm:git:ssh://git@github.com/Curzibn/Luban.git") url.set("https://github.com/Curzibn/Luban") } } } ================================================ FILE: luban/consumer-rules.pro ================================================ -keep class top.zibin.luban.compression.TurboJpegNative { native ; } ================================================ FILE: luban/proguard-rules.pro ================================================ # Add project specific ProGuard rules here. # You can control the set of applied configuration files using the # proguardFiles setting in build.gradle. # # For more details, see # http://developer.android.com/guide/developing/tools/proguard.html # If your project uses WebView with JS, uncomment the following # and specify the fully qualified class name to the JavaScript interface # class: #-keepclassmembers class fqcn.of.javascript.interface.for.webview { # public *; #} # Uncomment this to preserve the line number information for # debugging stack traces. #-keepattributes SourceFile,LineNumberTable # If you keep the line number information, uncomment this to # hide the original source file name. #-renamesourcefileattribute SourceFile ================================================ FILE: luban/src/androidTest/java/top/zibin/luban/ExampleInstrumentedTest.kt ================================================ package top.zibin.luban import androidx.test.platform.app.InstrumentationRegistry import androidx.test.ext.junit.runners.AndroidJUnit4 import org.junit.Test import org.junit.runner.RunWith import org.junit.Assert.* /** * 在 Android 设备上执行的仪器测试。 * * 参见 [测试文档](http://d.android.com/tools/testing)。 * * Instrumented test, which will execute on an Android device. * * See [testing documentation](http://d.android.com/tools/testing). */ @RunWith(AndroidJUnit4::class) class ExampleInstrumentedTest { @Test fun useAppContext() { val appContext = InstrumentationRegistry.getInstrumentation().targetContext assertEquals("top.zibin.luban.test", appContext.packageName) } } ================================================ FILE: luban/src/main/AndroidManifest.xml ================================================ ================================================ FILE: luban/src/main/cpp/CMakeLists.txt ================================================ cmake_minimum_required(VERSION 3.22.1) project(turbojpeg-wrapper) set(CMAKE_CXX_STANDARD 17) set(CMAKE_CXX_STANDARD_REQUIRED ON) set(jniLibsDir "${CMAKE_SOURCE_DIR}/../jniLibs") add_library(turbojpeg SHARED IMPORTED) set_target_properties(turbojpeg PROPERTIES IMPORTED_LOCATION "${jniLibsDir}/${ANDROID_ABI}/libturbojpeg.so" ) add_library(turbojpeg-wrapper SHARED turbojpeg_wrapper.cpp ) target_include_directories(turbojpeg-wrapper PRIVATE ${CMAKE_CURRENT_SOURCE_DIR} ) find_library(log-lib log) target_link_libraries(turbojpeg-wrapper turbojpeg ${log-lib} android ) ================================================ FILE: luban/src/main/cpp/turbojpeg.h ================================================ /* * Copyright (C)2009-2015, 2017, 2020-2025 D. R. Commander. * All Rights Reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * - Redistributions of source code must retain the above copyright notice, * this list of conditions and the following disclaimer. * - Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * - Neither the name of the libjpeg-turbo Project nor the names of its * contributors may be used to endorse or promote products derived from this * software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS", * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ #ifndef __TURBOJPEG_H__ #define __TURBOJPEG_H__ #include #if defined(_WIN32) && defined(DLLDEFINE) #define DLLEXPORT __declspec(dllexport) #else #define DLLEXPORT #endif #define DLLCALL /** * @addtogroup TurboJPEG * TurboJPEG API. This API provides an interface for generating, decoding, and * transforming planar YUV and JPEG images in memory. * * @anchor YUVnotes * YUV Image Format Notes * ---------------------- * Technically, the JPEG format uses the YCbCr colorspace (which is technically * not a colorspace but a color transform), but per the convention of the * digital video community, the TurboJPEG API uses "YUV" to refer to an image * format consisting of Y, Cb, and Cr image planes. * * Each plane is simply a 2D array of bytes, each byte representing the value * of one of the components (Y, Cb, or Cr) at a particular location in the * image. The width and height of each plane are determined by the image * width, height, and level of chrominance subsampling. The luminance plane * width is the image width padded to the nearest multiple of the horizontal * subsampling factor (1 in the case of 4:4:4, grayscale, 4:4:0, or 4:4:1; 2 in * the case of 4:2:2 or 4:2:0; 4 in the case of 4:1:1.) Similarly, the * luminance plane height is the image height padded to the nearest multiple of * the vertical subsampling factor (1 in the case of 4:4:4, 4:2:2, grayscale, * or 4:1:1; 2 in the case of 4:2:0 or 4:4:0; 4 in the case of 4:4:1.) This is * irrespective of any additional padding that may be specified as an argument * to the various YUV functions. The chrominance plane width is equal to the * luminance plane width divided by the horizontal subsampling factor, and the * chrominance plane height is equal to the luminance plane height divided by * the vertical subsampling factor. * * For example, if the source image is 35 x 35 pixels and 4:2:2 subsampling is * used, then the luminance plane would be 36 x 35 bytes, and each of the * chrominance planes would be 18 x 35 bytes. If you specify a row alignment * of 4 bytes on top of this, then the luminance plane would be 36 x 35 bytes, * and each of the chrominance planes would be 20 x 35 bytes. * * @{ */ /** * The number of initialization options */ #define TJ_NUMINIT 3 /** * Initialization options */ enum TJINIT { /** * Initialize the TurboJPEG instance for compression. */ TJINIT_COMPRESS, /** * Initialize the TurboJPEG instance for decompression. */ TJINIT_DECOMPRESS, /** * Initialize the TurboJPEG instance for lossless transformation (both * compression and decompression.) */ TJINIT_TRANSFORM }; /** * The number of chrominance subsampling options */ #define TJ_NUMSAMP 7 /** * Chrominance subsampling options * * When pixels are converted from RGB to YCbCr (see #TJCS_YCbCr) or from CMYK * to YCCK (see #TJCS_YCCK) as part of the JPEG compression process, some of * the Cb and Cr (chrominance) components can be discarded or averaged together * to produce a smaller image with little perceptible loss of image quality. * (The human eye is more sensitive to small changes in brightness than to * small changes in color.) This is called "chrominance subsampling". */ enum TJSAMP { /** * 4:4:4 chrominance subsampling (no chrominance subsampling) * * The JPEG or YUV image will contain one chrominance component for every * pixel in the source image. */ TJSAMP_444, /** * 4:2:2 chrominance subsampling * * The JPEG or YUV image will contain one chrominance component for every 2x1 * block of pixels in the source image. */ TJSAMP_422, /** * 4:2:0 chrominance subsampling * * The JPEG or YUV image will contain one chrominance component for every 2x2 * block of pixels in the source image. */ TJSAMP_420, /** * Grayscale * * The JPEG or YUV image will contain no chrominance components. */ TJSAMP_GRAY, /** * 4:4:0 chrominance subsampling * * The JPEG or YUV image will contain one chrominance component for every 1x2 * block of pixels in the source image. * * @note 4:4:0 subsampling is not fully accelerated in libjpeg-turbo. */ TJSAMP_440, /** * 4:1:1 chrominance subsampling * * The JPEG or YUV image will contain one chrominance component for every 4x1 * block of pixels in the source image. All else being equal, a JPEG image * with 4:1:1 subsampling is almost exactly the same size as a JPEG image * with 4:2:0 subsampling, and in the aggregate, both subsampling methods * produce approximately the same perceptual quality. However, 4:1:1 is * better able to reproduce sharp horizontal features. * * @note 4:1:1 subsampling is not fully accelerated in libjpeg-turbo. */ TJSAMP_411, /** * 4:4:1 chrominance subsampling * * The JPEG or YUV image will contain one chrominance component for every 1x4 * block of pixels in the source image. All else being equal, a JPEG image * with 4:4:1 subsampling is almost exactly the same size as a JPEG image * with 4:2:0 subsampling, and in the aggregate, both subsampling methods * produce approximately the same perceptual quality. However, 4:4:1 is * better able to reproduce sharp vertical features. * * @note 4:4:1 subsampling is not fully accelerated in libjpeg-turbo. */ TJSAMP_441, /** * Unknown subsampling * * The JPEG image uses an unusual type of chrominance subsampling. Such * images can be decompressed into packed-pixel images, but they cannot be * - decompressed into planar YUV images, * - losslessly transformed if #TJXOPT_CROP is specified and #TJXOPT_GRAY is * not specified, or * - partially decompressed using a cropping region. */ TJSAMP_UNKNOWN = -1 }; /** * iMCU width (in pixels) for a given level of chrominance subsampling * * In a typical lossy JPEG image, 8x8 blocks of DCT coefficients for each * component are interleaved in a single scan. If the image uses chrominance * subsampling, then multiple luminance blocks are stored together, followed by * a single block for each chrominance component. The minimum set of * full-resolution luminance block(s) and corresponding (possibly subsampled) * chrominance blocks necessary to represent at least one DCT block per * component is called a "Minimum Coded Unit" or "MCU". (For example, an MCU * in an interleaved lossy JPEG image that uses 4:2:2 subsampling consists of * two luminance blocks followed by one block for each chrominance component.) * In a non-interleaved lossy JPEG image, each component is stored in a * separate scan, and an MCU is a single DCT block, so we use the term "iMCU" * (interleaved MCU) to refer to the equivalent of an MCU in an interleaved * JPEG image. For the common case of interleaved JPEG images, an iMCU is the * same as an MCU. * * iMCU sizes: * - 8x8 for no subsampling or grayscale * - 16x8 for 4:2:2 * - 8x16 for 4:4:0 * - 16x16 for 4:2:0 * - 32x8 for 4:1:1 * - 8x32 for 4:4:1 */ static const int tjMCUWidth[TJ_NUMSAMP] = { 8, 16, 16, 8, 8, 32, 8 }; /** * iMCU height (in pixels) for a given level of chrominance subsampling * * In a typical lossy JPEG image, 8x8 blocks of DCT coefficients for each * component are interleaved in a single scan. If the image uses chrominance * subsampling, then multiple luminance blocks are stored together, followed by * a single block for each chrominance component. The minimum set of * full-resolution luminance block(s) and corresponding (possibly subsampled) * chrominance blocks necessary to represent at least one DCT block per * component is called a "Minimum Coded Unit" or "MCU". (For example, an MCU * in an interleaved lossy JPEG image that uses 4:2:2 subsampling consists of * two luminance blocks followed by one block for each chrominance component.) * In a non-interleaved lossy JPEG image, each component is stored in a * separate scan, and an MCU is a single DCT block, so we use the term "iMCU" * (interleaved MCU) to refer to the equivalent of an MCU in an interleaved * JPEG image. For the common case of interleaved JPEG images, an iMCU is the * same as an MCU. * * iMCU sizes: * - 8x8 for no subsampling or grayscale * - 16x8 for 4:2:2 * - 8x16 for 4:4:0 * - 16x16 for 4:2:0 * - 32x8 for 4:1:1 * - 8x32 for 4:4:1 */ static const int tjMCUHeight[TJ_NUMSAMP] = { 8, 8, 16, 8, 16, 8, 32 }; /** * The number of pixel formats */ #define TJ_NUMPF 12 /** * Pixel formats */ enum TJPF { /** * RGB pixel format * * The red, green, and blue components in the image are stored in 3-sample * pixels in the order R, G, B from lowest to highest memory address within * each pixel. */ TJPF_RGB, /** * BGR pixel format * * The red, green, and blue components in the image are stored in 3-sample * pixels in the order B, G, R from lowest to highest memory address within * each pixel. */ TJPF_BGR, /** * RGBX pixel format * * The red, green, and blue components in the image are stored in 4-sample * pixels in the order R, G, B from lowest to highest memory address within * each pixel. The X component is ignored when compressing/encoding and * undefined when decompressing/decoding. */ TJPF_RGBX, /** * BGRX pixel format * * The red, green, and blue components in the image are stored in 4-sample * pixels in the order B, G, R from lowest to highest memory address within * each pixel. The X component is ignored when compressing/encoding and * undefined when decompressing/decoding. */ TJPF_BGRX, /** * XBGR pixel format * * The red, green, and blue components in the image are stored in 4-sample * pixels in the order R, G, B from highest to lowest memory address within * each pixel. The X component is ignored when compressing/encoding and * undefined when decompressing/decoding. */ TJPF_XBGR, /** * XRGB pixel format * * The red, green, and blue components in the image are stored in 4-sample * pixels in the order B, G, R from highest to lowest memory address within * each pixel. The X component is ignored when compressing/encoding and * undefined when decompressing/decoding. */ TJPF_XRGB, /** * Grayscale pixel format * * Each 1-sample pixel represents a luminance (brightness) level from 0 to * the maximum sample value (which is, for instance, 255 for 8-bit samples or * 4095 for 12-bit samples or 65535 for 16-bit samples.) */ TJPF_GRAY, /** * RGBA pixel format * * This is the same as @ref TJPF_RGBX, except that when * decompressing/decoding, the X component is guaranteed to be equal to the * maximum sample value, which can be interpreted as an opaque alpha channel. */ TJPF_RGBA, /** * BGRA pixel format * * This is the same as @ref TJPF_BGRX, except that when * decompressing/decoding, the X component is guaranteed to be equal to the * maximum sample value, which can be interpreted as an opaque alpha channel. */ TJPF_BGRA, /** * ABGR pixel format * * This is the same as @ref TJPF_XBGR, except that when * decompressing/decoding, the X component is guaranteed to be equal to the * maximum sample value, which can be interpreted as an opaque alpha channel. */ TJPF_ABGR, /** * ARGB pixel format * * This is the same as @ref TJPF_XRGB, except that when * decompressing/decoding, the X component is guaranteed to be equal to the * maximum sample value, which can be interpreted as an opaque alpha channel. */ TJPF_ARGB, /** * CMYK pixel format * * Unlike RGB, which is an additive color model used primarily for display, * CMYK (Cyan/Magenta/Yellow/Key) is a subtractive color model used primarily * for printing. In the CMYK color model, the value of each color component * typically corresponds to an amount of cyan, magenta, yellow, or black ink * that is applied to a white background. In order to convert between CMYK * and RGB, it is necessary to use a color management system (CMS.) A CMS * will attempt to map colors within the printer's gamut to perceptually * similar colors in the display's gamut and vice versa, but the mapping is * typically not 1:1 or reversible, nor can it be defined with a simple * formula. Thus, such a conversion is out of scope for a codec library. * However, the TurboJPEG API allows for compressing packed-pixel CMYK images * into YCCK JPEG images (see #TJCS_YCCK) and decompressing YCCK JPEG images * into packed-pixel CMYK images. */ TJPF_CMYK, /** * Unknown pixel format * * Currently this is only used by #tj3LoadImage8(), #tj3LoadImage12(), and * #tj3LoadImage16(). */ TJPF_UNKNOWN = -1 }; /** * Red offset (in samples) for a given pixel format * * This specifies the number of samples that the red component is offset from * the start of the pixel. For instance, if an 8-bit-per-component pixel of * format TJPF_BGRX is stored in `unsigned char pixel[]`, then the red * component is `pixel[tjRedOffset[TJPF_BGRX]]`. The offset is -1 if the pixel * format does not have a red component. */ static const int tjRedOffset[TJ_NUMPF] = { 0, 2, 0, 2, 3, 1, -1, 0, 2, 3, 1, -1 }; /** * Green offset (in samples) for a given pixel format * * This specifies the number of samples that the green component is offset from * the start of the pixel. For instance, if an 8-bit-per-component pixel of * format TJPF_BGRX is stored in `unsigned char pixel[]`, then the green * component is `pixel[tjGreenOffset[TJPF_BGRX]]`. The offset is -1 if the * pixel format does not have a green component. */ static const int tjGreenOffset[TJ_NUMPF] = { 1, 1, 1, 1, 2, 2, -1, 1, 1, 2, 2, -1 }; /** * Blue offset (in samples) for a given pixel format * * This specifies the number of samples that the blue component is offset from * the start of the pixel. For instance, if an 8-bit-per-component pixel of * format TJPF_BGRX is stored in `unsigned char pixel[]`, then the blue * component is `pixel[tjBlueOffset[TJPF_BGRX]]`. The offset is -1 if the * pixel format does not have a blue component. */ static const int tjBlueOffset[TJ_NUMPF] = { 2, 0, 2, 0, 1, 3, -1, 2, 0, 1, 3, -1 }; /** * Alpha offset (in samples) for a given pixel format * * This specifies the number of samples that the alpha component is offset from * the start of the pixel. For instance, if an 8-bit-per-component pixel of * format TJPF_BGRA is stored in `unsigned char pixel[]`, then the alpha * component is `pixel[tjAlphaOffset[TJPF_BGRA]]`. The offset is -1 if the * pixel format does not have an alpha component. */ static const int tjAlphaOffset[TJ_NUMPF] = { -1, -1, -1, -1, -1, -1, -1, 3, 3, 0, 0, -1 }; /** * Pixel size (in samples) for a given pixel format */ static const int tjPixelSize[TJ_NUMPF] = { 3, 3, 4, 4, 4, 4, 1, 4, 4, 4, 4, 4 }; /** * The number of JPEG colorspaces */ #define TJ_NUMCS 5 /** * JPEG colorspaces */ enum TJCS { /** * RGB colorspace * * When generating the JPEG image, the R, G, and B components in the source * image are reordered into image planes, but no colorspace conversion or * subsampling is performed. RGB JPEG images can be generated from and * decompressed to packed-pixel images with any of the extended RGB or * grayscale pixel formats, but they cannot be generated from or * decompressed to planar YUV images. */ TJCS_RGB, /** * YCbCr colorspace * * YCbCr is not an absolute colorspace but rather a mathematical * transformation of RGB designed solely for storage and transmission. YCbCr * images must be converted to RGB before they can be displayed. In the * YCbCr colorspace, the Y (luminance) component represents the black & white * portion of the original image, and the Cb and Cr (chrominance) components * represent the color portion of the original image. Historically, the * analog equivalent of this transformation allowed the same signal to be * displayed to both black & white and color televisions, but JPEG images use * YCbCr primarily because it allows the color data to be optionally * subsampled in order to reduce network and disk usage. YCbCr is the most * common JPEG colorspace, and YCbCr JPEG images can be generated from and * decompressed to packed-pixel images with any of the extended RGB or * grayscale pixel formats. YCbCr JPEG images can also be generated from * and decompressed to planar YUV images. */ TJCS_YCbCr, /** * Grayscale colorspace * * The JPEG image retains only the luminance data (Y component), and any * color data from the source image is discarded. Grayscale JPEG images can * be generated from and decompressed to packed-pixel images with any of the * extended RGB or grayscale pixel formats, or they can be generated from * and decompressed to planar YUV images. */ TJCS_GRAY, /** * CMYK colorspace * * When generating the JPEG image, the C, M, Y, and K components in the * source image are reordered into image planes, but no colorspace conversion * or subsampling is performed. CMYK JPEG images can only be generated from * and decompressed to packed-pixel images with the CMYK pixel format. */ TJCS_CMYK, /** * YCCK colorspace * * YCCK (AKA "YCbCrK") is not an absolute colorspace but rather a * mathematical transformation of CMYK designed solely for storage and * transmission. It is to CMYK as YCbCr is to RGB. CMYK pixels can be * reversibly transformed into YCCK, and as with YCbCr, the chrominance * components in the YCCK pixels can be subsampled without incurring major * perceptual loss. YCCK JPEG images can only be generated from and * decompressed to packed-pixel images with the CMYK pixel format. */ TJCS_YCCK }; /** * Parameters */ enum TJPARAM { /** * Error handling behavior * * **Value** * - `0` *[default]* Allow the current compression/decompression/transform * operation to complete unless a fatal error is encountered. * - `1` Immediately discontinue the current * compression/decompression/transform operation if a warning (non-fatal * error) occurs. */ TJPARAM_STOPONWARNING, /** * Row order in packed-pixel source/destination images * * **Value** * - `0` *[default]* top-down (X11) order * - `1` bottom-up (Windows, OpenGL) order */ TJPARAM_BOTTOMUP, /** * JPEG destination buffer (re)allocation [compression, lossless * transformation] * * **Value** * - `0` *[default]* Attempt to allocate or reallocate the JPEG destination * buffer as needed. * - `1` Generate an error if the JPEG destination buffer is invalid or too * small. */ TJPARAM_NOREALLOC, /** * Perceptual quality of lossy JPEG images [compression only] * * **Value** * - `1`-`100` (`1` = worst quality but best compression, `100` = best * quality but worst compression) *[no default; must be explicitly * specified]* */ TJPARAM_QUALITY, /** * Chrominance subsampling level * * The JPEG or YUV image uses (decompression, decoding) or will use (lossy * compression, encoding) the specified level of chrominance subsampling. * * **Value** * - One of the @ref TJSAMP "chrominance subsampling options" *[no default; * must be explicitly specified for lossy compression, encoding, and * decoding]* */ TJPARAM_SUBSAMP, /** * JPEG width (in pixels) [decompression only, read-only] */ TJPARAM_JPEGWIDTH, /** * JPEG height (in pixels) [decompression only, read-only] */ TJPARAM_JPEGHEIGHT, /** * Data precision (bits per sample) * * The JPEG image uses (decompression) or will use (lossless compression) the * specified number of bits per sample. This parameter also specifies the * target data precision when loading a PBMPLUS file with #tj3LoadImage8(), * #tj3LoadImage12(), or #tj3LoadImage16() and the source data precision when * saving a PBMPLUS file with #tj3SaveImage8(), #tj3SaveImage12(), or * #tj3SaveImage16(). * * The data precision is the number of bits in the maximum sample value, * which may not be the same as the width of the data type used to store the * sample. * * **Value** * - `8` or `12` for lossy JPEG images; `2` to `16` for lossless JPEG and * PBMPLUS images * * 12-bit JPEG data precision implies #TJPARAM_OPTIMIZE unless * #TJPARAM_ARITHMETIC is set. */ TJPARAM_PRECISION, /** * JPEG colorspace * * The JPEG image uses (decompression) or will use (lossy compression) the * specified colorspace. * * **Value** * - One of the @ref TJCS "JPEG colorspaces" *[default for lossy compression: * automatically selected based on the subsampling level and pixel format]* */ TJPARAM_COLORSPACE, /** * Chrominance upsampling algorithm [lossy decompression only] * * **Value** * - `0` *[default]* Use smooth upsampling when decompressing a JPEG image * that was generated using chrominance subsampling. This creates a smooth * transition between neighboring chrominance components in order to reduce * upsampling artifacts in the decompressed image. * - `1` Use the fastest chrominance upsampling algorithm available, which * may combine upsampling with color conversion. */ TJPARAM_FASTUPSAMPLE, /** * DCT/IDCT algorithm [lossy compression and decompression] * * **Value** * - `0` *[default]* Use the most accurate DCT/IDCT algorithm available. * - `1` Use the fastest DCT/IDCT algorithm available. * * This parameter is provided mainly for backward compatibility with libjpeg, * which historically implemented several different DCT/IDCT algorithms * because of performance limitations with 1990s CPUs. In the libjpeg-turbo * implementation of the TurboJPEG API: * - The "fast" and "accurate" DCT/IDCT algorithms perform similarly on * modern x86/x86-64 CPUs that support AVX2 instructions. * - The "fast" algorithm is generally only about 5-15% faster than the * "accurate" algorithm on other types of CPUs. * - The difference in accuracy between the "fast" and "accurate" algorithms * is the most pronounced at JPEG quality levels above 90 and tends to be * more pronounced with decompression than with compression. * - For JPEG quality levels above 97, the "fast" algorithm degrades and is * not fully accelerated, so it is slower than the "accurate" algorithm. */ TJPARAM_FASTDCT, /** * Huffman table optimization [lossy compression, lossless transformation] * * **Value** * - `0` *[default]* The JPEG image will use the default Huffman tables. * - `1` Optimal Huffman tables will be computed for the JPEG image. For * lossless transformation, this can also be specified using * #TJXOPT_OPTIMIZE. * * Huffman table optimization improves compression slightly (generally 5% or * less), but it reduces compression performance considerably. */ TJPARAM_OPTIMIZE, /** * Progressive JPEG * * In a progressive JPEG image, the DCT coefficients are split across * multiple "scans" of increasing quality. Thus, a low-quality scan * containing the lowest-frequency DCT coefficients can be transmitted first * and refined with subsequent higher-quality scans containing * higher-frequency DCT coefficients. When using Huffman entropy coding, the * progressive JPEG format also provides an "end-of-bands (EOB) run" feature * that allows large groups of zeroes, potentially spanning multiple MCUs, * to be represented using only a few bytes. * * **Value** * - `0` *[default for compression, lossless transformation]* The lossy JPEG * image is (decompression) or will be (compression, lossless transformation) * single-scan. * - `1` The lossy JPEG image is (decompression) or will be (compression, * lossless transformation) progressive. For lossless transformation, this * can also be specified using #TJXOPT_PROGRESSIVE. * * Progressive JPEG images generally have better compression ratios than * single-scan JPEG images (much better if the image has large areas of solid * color), but progressive JPEG compression and decompression is considerably * slower than single-scan JPEG compression and decompression. Can be * combined with #TJPARAM_ARITHMETIC. Implies #TJPARAM_OPTIMIZE unless * #TJPARAM_ARITHMETIC is also set. */ TJPARAM_PROGRESSIVE, /** * Progressive JPEG scan limit for lossy JPEG images [decompression, lossless * transformation] * * Setting this parameter causes the decompression and transform functions to * return an error if the number of scans in a progressive JPEG image exceeds * the specified limit. The primary purpose of this is to allow * security-critical applications to guard against an exploit of the * progressive JPEG format described in * this report. * * **Value** * - maximum number of progressive JPEG scans that the decompression and * transform functions will process *[default: `0` (no limit)]* * * @see #TJPARAM_PROGRESSIVE */ TJPARAM_SCANLIMIT, /** * Arithmetic entropy coding * * **Value** * - `0` *[default for compression, lossless transformation]* The lossy JPEG * image uses (decompression) or will use (compression, lossless * transformation) Huffman entropy coding. * - `1` The lossy JPEG image uses (decompression) or will use (compression, * lossless transformation) arithmetic entropy coding. For lossless * transformation, this can also be specified using #TJXOPT_ARITHMETIC. * * Arithmetic entropy coding generally improves compression relative to * Huffman entropy coding, but it reduces compression and decompression * performance considerably. Can be combined with #TJPARAM_PROGRESSIVE. */ TJPARAM_ARITHMETIC, /** * Lossless JPEG * * **Value** * - `0` *[default for compression]* The JPEG image is (decompression) or * will be (compression) lossy/DCT-based. * - `1` The JPEG image is (decompression) or will be (compression) * lossless/predictive. * * In most cases, lossless JPEG compression and decompression is considerably * slower than lossy JPEG compression and decompression, and lossless JPEG * images are much larger than lossy JPEG images. Thus, lossless JPEG images * are typically used only for applications that require mathematically * lossless compression. Also note that the following features are not * available with lossless JPEG images: * - Colorspace conversion (lossless JPEG images always use #TJCS_RGB, * #TJCS_GRAY, or #TJCS_CMYK, depending on the pixel format of the source * image) * - Chrominance subsampling (lossless JPEG images always use #TJSAMP_444) * - JPEG quality selection * - DCT/IDCT algorithm selection * - Progressive JPEG * - Arithmetic entropy coding * - Compression from/decompression to planar YUV images (this parameter is * ignored by #tj3CompressFromYUV8() and #tj3CompressFromYUVPlanes8()) * - Decompression scaling * - Lossless transformation * * @see #TJPARAM_LOSSLESSPSV, #TJPARAM_LOSSLESSPT */ TJPARAM_LOSSLESS, /** * Lossless JPEG predictor selection value (PSV) * * **Value** * - `1`-`7` *[default for compression: `1`]* * * Lossless JPEG compression shares no algorithms with lossy JPEG * compression. Instead, it uses differential pulse-code modulation (DPCM), * an algorithm whereby each sample is encoded as the difference between the * sample's value and a "predictor", which is based on the values of * neighboring samples. If Ra is the sample immediately to the left of the * current sample, Rb is the sample immediately above the current sample, and * Rc is the sample diagonally to the left and above the current sample, then * the relationship between the predictor selection value and the predictor * is as follows: * * PSV | Predictor * ----|---------- * 1 | Ra * 2 | Rb * 3 | Rc * 4 | Ra + Rb – Rc * 5 | Ra + (Rb – Rc) / 2 * 6 | Rb + (Ra – Rc) / 2 * 7 | (Ra + Rb) / 2 * * Predictors 1-3 are 1-dimensional predictors, whereas Predictors 4-7 are * 2-dimensional predictors. The best predictor for a particular image * depends on the image. * * @see #TJPARAM_LOSSLESS */ TJPARAM_LOSSLESSPSV, /** * Lossless JPEG point transform (Pt) * * **Value** * - `0` through ***precision*** *- 1*, where ***precision*** is the JPEG * data precision in bits *[default for compression: `0`]* * * A point transform value of `0` is necessary in order to generate a fully * lossless JPEG image. (A non-zero point transform value right-shifts the * input samples by the specified number of bits, which is effectively a form * of lossy color quantization.) * * @see #TJPARAM_LOSSLESS, #TJPARAM_PRECISION */ TJPARAM_LOSSLESSPT, /** * JPEG restart marker interval in MCUs [lossy compression, * lossless transformation] * * The nature of entropy coding is such that a corrupt JPEG image cannot * be decompressed beyond the point of corruption unless it contains restart * markers. A restart marker stops and restarts the entropy coding algorithm * so that, if a JPEG image is corrupted, decompression can resume at the * next marker. Thus, adding more restart markers improves the fault * tolerance of the JPEG image, but adding too many restart markers can * adversely affect the compression ratio and performance. * * In typical JPEG images, an MCU (Minimum Coded Unit) is the minimum set of * interleaved "data units" (8x8 DCT blocks if the image is lossy or samples * if the image is lossless) necessary to represent at least one data unit * per component. (For example, an MCU in an interleaved lossy JPEG image * that uses 4:2:2 subsampling consists of two luminance blocks followed by * one block for each chrominance component.) In single-component or * non-interleaved JPEG images, an MCU is the same as a data unit. * * **Value** * - the number of MCUs between each restart marker *[default: `0` (no * restart markers)]* * * Setting this parameter to a non-zero value sets #TJPARAM_RESTARTROWS to 0. */ TJPARAM_RESTARTBLOCKS, /** * JPEG restart marker interval in MCU rows [compression, * lossless transformation] * * See #TJPARAM_RESTARTBLOCKS for a description of restart markers and MCUs. * An MCU row is a row of MCUs spanning the entire width of the image. * * **Value** * - the number of MCU rows between each restart marker *[default: `0` (no * restart markers)]* * * Setting this parameter to a non-zero value sets #TJPARAM_RESTARTBLOCKS to * 0. */ TJPARAM_RESTARTROWS, /** * JPEG horizontal pixel density * * **Value** * - The JPEG image has (decompression) or will have (compression) the * specified horizontal pixel density *[default for compression: `1`]*. * * This value is stored in or read from the JPEG header. It does not affect * the contents of the JPEG image. Note that this parameter is set by * #tj3LoadImage8() when loading a Windows BMP file that contains pixel * density information, and the value of this parameter is stored to a * Windows BMP file by #tj3SaveImage8() if the value of #TJPARAM_DENSITYUNITS * is `2`. * * This parameter has no effect unless the JPEG colorspace (see * #TJPARAM_COLORSPACE) is #TJCS_YCbCr or #TJCS_GRAY. * * @see TJPARAM_DENSITYUNITS */ TJPARAM_XDENSITY, /** * JPEG vertical pixel density * * **Value** * - The JPEG image has (decompression) or will have (compression) the * specified vertical pixel density *[default for compression: `1`]*. * * This value is stored in or read from the JPEG header. It does not affect * the contents of the JPEG image. Note that this parameter is set by * #tj3LoadImage8() when loading a Windows BMP file that contains pixel * density information, and the value of this parameter is stored to a * Windows BMP file by #tj3SaveImage8() if the value of #TJPARAM_DENSITYUNITS * is `2`. * * This parameter has no effect unless the JPEG colorspace (see * #TJPARAM_COLORSPACE) is #TJCS_YCbCr or #TJCS_GRAY. * * @see TJPARAM_DENSITYUNITS */ TJPARAM_YDENSITY, /** * JPEG pixel density units * * **Value** * - `0` *[default for compression]* The pixel density of the JPEG image is * expressed (decompression) or will be expressed (compression) in unknown * units. * - `1` The pixel density of the JPEG image is expressed (decompression) or * will be expressed (compression) in units of pixels/inch. * - `2` The pixel density of the JPEG image is expressed (decompression) or * will be expressed (compression) in units of pixels/cm. * * This value is stored in or read from the JPEG header. It does not affect * the contents of the JPEG image. Note that this parameter is set by * #tj3LoadImage8() when loading a Windows BMP file that contains pixel * density information, and the value of this parameter is stored to a * Windows BMP file by #tj3SaveImage8() if the value is `2`. * * This parameter has no effect unless the JPEG colorspace (see * #TJPARAM_COLORSPACE) is #TJCS_YCbCr or #TJCS_GRAY. * * @see TJPARAM_XDENSITY, TJPARAM_YDENSITY */ TJPARAM_DENSITYUNITS, /** * Memory limit for intermediate buffers * * **Value** * - the maximum amount of memory (in megabytes) that will be allocated for * intermediate buffers, which are used with progressive JPEG compression and * decompression, Huffman table optimization, lossless JPEG compression, and * lossless transformation *[default: `0` (no limit)]* */ TJPARAM_MAXMEMORY, /** * Image size limit [decompression, lossless transformation, packed-pixel * image loading] * * Setting this parameter causes the decompression, transform, and image * loading functions to return an error if the number of pixels in the source * image exceeds the specified limit. This allows security-critical * applications to guard against excessive memory consumption. * * **Value** * - maximum number of pixels that the decompression, transform, and image * loading functions will process *[default: `0` (no limit)]* */ TJPARAM_MAXPIXELS, /** * Marker copying behavior [decompression, lossless transformation] * * **Value [lossless transformation]** * - `0` Do not copy any extra markers (including comments, JFIF thumbnails, * Exif data, and ICC profile data) from the source image to the destination * image. * - `1` Do not copy any extra markers, except comment (COM) markers, from * the source image to the destination image. * - `2` *[default]* Copy all extra markers from the source image to the * destination image. * - `3` Copy all extra markers, except ICC profile data (APP2 markers), from * the source image to the destination image. * - `4` Do not copy any extra markers, except ICC profile data (APP2 * markers), from the source image to the destination image. * * #TJXOPT_COPYNONE overrides this parameter for a particular transform. * This parameter overrides any ICC profile that was previously associated * with the TurboJPEG instance using #tj3SetICCProfile(). * * When decompressing, #tj3DecompressHeader() extracts the ICC profile from a * JPEG image if this parameter is set to `2` or `4`. #tj3GetICCProfile() * can then be used to retrieve the profile. */ TJPARAM_SAVEMARKERS }; /** * The number of error codes */ #define TJ_NUMERR 2 /** * Error codes */ enum TJERR { /** * The error was non-fatal and recoverable, but the destination image may * still be corrupt. */ TJERR_WARNING, /** * The error was fatal and non-recoverable. */ TJERR_FATAL }; /** * The number of transform operations */ #define TJ_NUMXOP 8 /** * Transform operations for #tj3Transform() */ enum TJXOP { /** * Do not transform the position of the image pixels. */ TJXOP_NONE, /** * Flip (mirror) image horizontally. This transform is imperfect if there * are any partial iMCUs on the right edge (see #TJXOPT_PERFECT.) */ TJXOP_HFLIP, /** * Flip (mirror) image vertically. This transform is imperfect if there are * any partial iMCUs on the bottom edge (see #TJXOPT_PERFECT.) */ TJXOP_VFLIP, /** * Transpose image (flip/mirror along upper left to lower right axis.) This * transform is always perfect. */ TJXOP_TRANSPOSE, /** * Transverse transpose image (flip/mirror along upper right to lower left * axis.) This transform is imperfect if there are any partial iMCUs in the * image (see #TJXOPT_PERFECT.) */ TJXOP_TRANSVERSE, /** * Rotate image clockwise by 90 degrees. This transform is imperfect if * there are any partial iMCUs on the bottom edge (see #TJXOPT_PERFECT.) */ TJXOP_ROT90, /** * Rotate image 180 degrees. This transform is imperfect if there are any * partial iMCUs in the image (see #TJXOPT_PERFECT.) */ TJXOP_ROT180, /** * Rotate image counter-clockwise by 90 degrees. This transform is imperfect * if there are any partial iMCUs on the right edge (see #TJXOPT_PERFECT.) */ TJXOP_ROT270 }; /** * This option causes #tj3Transform() to return an error if the transform is * not perfect. Lossless transforms operate on iMCUs, the size of which * depends on the level of chrominance subsampling used (see #tjMCUWidth and * #tjMCUHeight.) If the image's width or height is not evenly divisible by * the iMCU size, then there will be partial iMCUs on the right and/or bottom * edges. It is not possible to move these partial iMCUs to the top or left of * the image, so any transform that would require that is "imperfect." If this * option is not specified, then any partial iMCUs that cannot be transformed * will be left in place, which will create odd-looking strips on the right or * bottom edge of the image. */ #define TJXOPT_PERFECT (1 << 0) /** * Discard any partial iMCUs that cannot be transformed. */ #define TJXOPT_TRIM (1 << 1) /** * Enable lossless cropping. See #tj3Transform() for more information. */ #define TJXOPT_CROP (1 << 2) /** * Discard the color data in the source image, and generate a grayscale * destination image. */ #define TJXOPT_GRAY (1 << 3) /** * Do not generate a destination image. (This can be used in conjunction with * a custom filter to capture the transformed DCT coefficients without * transcoding them.) */ #define TJXOPT_NOOUTPUT (1 << 4) /** * Generate a progressive destination image instead of a single-scan * destination image. Progressive JPEG images generally have better * compression ratios than single-scan JPEG images (much better if the image * has large areas of solid color), but progressive JPEG decompression is * considerably slower than single-scan JPEG decompression. Can be combined * with #TJXOPT_ARITHMETIC. Implies #TJXOPT_OPTIMIZE unless #TJXOPT_ARITHMETIC * is also specified. */ #define TJXOPT_PROGRESSIVE (1 << 5) /** * Do not copy any extra markers (including Exif and ICC profile data) from the * source image to the destination image. */ #define TJXOPT_COPYNONE (1 << 6) /** * Enable arithmetic entropy coding in the destination image. Arithmetic * entropy coding generally improves compression relative to Huffman entropy * coding (the default), but it reduces decompression performance considerably. * Can be combined with #TJXOPT_PROGRESSIVE. */ #define TJXOPT_ARITHMETIC (1 << 7) /** * Enable Huffman table optimization for the destination image. Huffman table * optimization improves compression slightly (generally 5% or less.) */ #define TJXOPT_OPTIMIZE (1 << 8) /** * Scaling factor */ typedef struct { /** * Numerator */ int num; /** * Denominator */ int denom; } tjscalingfactor; /** * Cropping region */ typedef struct { /** * The left boundary of the cropping region. For lossless transformation, * this must be evenly divisible by the iMCU width (see #tjMCUWidth) of the * destination image. For decompression, this must be evenly divisible by * the scaled iMCU width of the source image. */ int x; /** * The upper boundary of the cropping region. For lossless transformation, * this must be evenly divisible by the iMCU height (see #tjMCUHeight) of the * destination image. */ int y; /** * The width of the cropping region. Setting this to 0 is the equivalent of * setting it to the width of the source JPEG image - x. */ int w; /** * The height of the cropping region. Setting this to 0 is the equivalent of * setting it to the height of the source JPEG image - y. */ int h; } tjregion; /** * A #tjregion structure that specifies no cropping */ static const tjregion TJUNCROPPED = { 0, 0, 0, 0 }; /** * Lossless transform */ typedef struct tjtransform { /** * Cropping region */ tjregion r; /** * One of the @ref TJXOP "transform operations" */ int op; /** * The bitwise OR of one of more of the @ref TJXOPT_ARITHMETIC * "transform options" */ int options; /** * Arbitrary data that can be accessed within the body of the callback * function */ void *data; /** * A callback function that can be used to modify the DCT coefficients after * they are losslessly transformed but before they are transcoded to a new * JPEG image. This allows for custom filters or other transformations to be * applied in the frequency domain. * * @param coeffs pointer to an array of transformed DCT coefficients. (NOTE: * This pointer is not guaranteed to be valid once the callback returns, so * applications wishing to hand off the DCT coefficients to another function * or library should make a copy of them within the body of the callback.) * * @param arrayRegion #tjregion structure containing the width and height of * the array pointed to by `coeffs` as well as its offset relative to the * component plane. TurboJPEG implementations may choose to split each * component plane into multiple DCT coefficient arrays and call the callback * function once for each array. * * @param planeRegion #tjregion structure containing the width and height of * the component plane to which `coeffs` belongs * * @param componentID ID number of the component plane to which `coeffs` * belongs. (Y, Cb, and Cr have, respectively, ID's of 0, 1, and 2 in * typical JPEG images.) * * @param transformID ID number of the transformed image to which `coeffs` * belongs. This is the same as the index of the transform in the * `transforms` array that was passed to #tj3Transform(). * * @param transform a pointer to a #tjtransform structure that specifies the * parameters and/or cropping region for this transform * * @return 0 if the callback was successful, or -1 if an error occurred. */ int (*customFilter) (short *coeffs, tjregion arrayRegion, tjregion planeRegion, int componentID, int transformID, struct tjtransform *transform); } tjtransform; /** * TurboJPEG instance handle */ typedef void *tjhandle; /** * Compute the scaled value of `dimension` using the given scaling factor. * This macro performs the integer equivalent of `ceil(dimension * * scalingFactor)`. */ #define TJSCALED(dimension, scalingFactor) \ (((dimension) * scalingFactor.num + scalingFactor.denom - 1) / \ scalingFactor.denom) /** * A #tjscalingfactor structure that specifies a scaling factor of 1/1 (no * scaling) */ static const tjscalingfactor TJUNSCALED = { 1, 1 }; #ifdef __cplusplus extern "C" { #endif /** * Create a new TurboJPEG instance. * * @param initType one of the @ref TJINIT "initialization options" * * @return a handle to the newly-created instance, or NULL if an error occurred * (see #tj3GetErrorStr().) */ DLLEXPORT tjhandle tj3Init(int initType); /** * Destroy a TurboJPEG instance. * * @param handle handle to a TurboJPEG instance. If the handle is NULL, then * this function has no effect. */ DLLEXPORT void tj3Destroy(tjhandle handle); /** * Returns a descriptive error message explaining why the last command failed. * * @param handle handle to a TurboJPEG instance, or NULL if the error was * generated by a global function (but note that retrieving the error message * for a global function is thread-safe only on platforms that support * thread-local storage.) * * @return a descriptive error message explaining why the last command failed. */ DLLEXPORT char *tj3GetErrorStr(tjhandle handle); /** * Returns a code indicating the severity of the last error. See * @ref TJERR "Error codes". * * @param handle handle to a TurboJPEG instance * * @return a code indicating the severity of the last error. See * @ref TJERR "Error codes". */ DLLEXPORT int tj3GetErrorCode(tjhandle handle); /** * Set the value of a parameter. * * @param handle handle to a TurboJPEG instance * * @param param one of the @ref TJPARAM "parameters" * * @param value value of the parameter (refer to @ref TJPARAM * "parameter documentation") * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr().) */ DLLEXPORT int tj3Set(tjhandle handle, int param, int value); /** * Get the value of a parameter. * * @param handle handle to a TurboJPEG instance * * @param param one of the @ref TJPARAM "parameters" * * @return the value of the specified parameter, or -1 if the value is unknown. */ DLLEXPORT int tj3Get(tjhandle handle, int param); /** * Allocate a byte buffer for use with TurboJPEG. You should always use this * function to allocate the JPEG destination buffer(s) for the compression and * transform functions unless you are disabling automatic buffer (re)allocation * (by setting #TJPARAM_NOREALLOC.) * * @param bytes the number of bytes to allocate * * @return a pointer to a newly-allocated buffer with the specified number of * bytes. * * @see tj3Free() */ DLLEXPORT void *tj3Alloc(size_t bytes); /** * Free a byte buffer previously allocated by TurboJPEG. You should always use * this function to free JPEG destination buffer(s) that were automatically * (re)allocated by the compression and transform functions or that were * manually allocated using #tj3Alloc(). * * @param buffer address of the buffer to free. If the address is NULL, then * this function has no effect. * * @see tj3Alloc() */ DLLEXPORT void tj3Free(void *buffer); /** * The maximum size of the buffer (in bytes) required to hold a JPEG image with * the given parameters. The number of bytes returned by this function is * larger than the size of the uncompressed source image. The reason for this * is that the JPEG format uses 16-bit coefficients, so it is possible for a * very high-quality source image with very high-frequency content to expand * rather than compress when converted to the JPEG format. Such images * represent very rare corner cases, but since there is no way to predict the * size of a JPEG image prior to compression, the corner cases have to be * handled. * * @param width width (in pixels) of the image * * @param height height (in pixels) of the image * * @param jpegSubsamp the level of chrominance subsampling to be used when * generating the JPEG image (see @ref TJSAMP * "Chrominance subsampling options".) #TJSAMP_UNKNOWN is treated like * #TJSAMP_444, since a buffer large enough to hold a JPEG image with no * subsampling should also be large enough to hold a JPEG image with an * arbitrary level of subsampling. Note that lossless JPEG images always * use #TJSAMP_444. * * @return the maximum size of the buffer (in bytes) required to hold the * image, or 0 if the arguments are out of bounds. */ DLLEXPORT size_t tj3JPEGBufSize(int width, int height, int jpegSubsamp); /** * The size of the buffer (in bytes) required to hold a unified planar YUV * image with the given parameters. * * @param width width (in pixels) of the image * * @param align row alignment (in bytes) of the image (must be a power of 2.) * Setting this parameter to n specifies that each row in each plane of the * image will be padded to the nearest multiple of n bytes (1 = unpadded.) * * @param height height (in pixels) of the image * * @param subsamp level of chrominance subsampling in the image (see * @ref TJSAMP "Chrominance subsampling options".) * * @return the size of the buffer (in bytes) required to hold the image, or 0 * if the arguments are out of bounds. */ DLLEXPORT size_t tj3YUVBufSize(int width, int align, int height, int subsamp); /** * The size of the buffer (in bytes) required to hold a YUV image plane with * the given parameters. * * @param componentID ID number of the image plane (0 = Y, 1 = U/Cb, 2 = V/Cr) * * @param width width (in pixels) of the YUV image. NOTE: This is the width of * the whole image, not the plane width. * * @param stride bytes per row in the image plane. Setting this to 0 is the * equivalent of setting it to the plane width. * * @param height height (in pixels) of the YUV image. NOTE: This is the height * of the whole image, not the plane height. * * @param subsamp level of chrominance subsampling in the image (see * @ref TJSAMP "Chrominance subsampling options".) * * @return the size of the buffer (in bytes) required to hold the YUV image * plane, or 0 if the arguments are out of bounds. */ DLLEXPORT size_t tj3YUVPlaneSize(int componentID, int width, int stride, int height, int subsamp); /** * The plane width of a YUV image plane with the given parameters. Refer to * @ref YUVnotes "YUV Image Format Notes" for a description of plane width. * * @param componentID ID number of the image plane (0 = Y, 1 = U/Cb, 2 = V/Cr) * * @param width width (in pixels) of the YUV image * * @param subsamp level of chrominance subsampling in the image (see * @ref TJSAMP "Chrominance subsampling options".) * * @return the plane width of a YUV image plane with the given parameters, or 0 * if the arguments are out of bounds. */ DLLEXPORT int tj3YUVPlaneWidth(int componentID, int width, int subsamp); /** * The plane height of a YUV image plane with the given parameters. Refer to * @ref YUVnotes "YUV Image Format Notes" for a description of plane height. * * @param componentID ID number of the image plane (0 = Y, 1 = U/Cb, 2 = V/Cr) * * @param height height (in pixels) of the YUV image * * @param subsamp level of chrominance subsampling in the image (see * @ref TJSAMP "Chrominance subsampling options".) * * @return the plane height of a YUV image plane with the given parameters, or * 0 if the arguments are out of bounds. */ DLLEXPORT int tj3YUVPlaneHeight(int componentID, int height, int subsamp); /** * Embed an ICC (International Color Consortium) color management profile in * JPEG images generated by subsequent compression and lossless transformation * operations. * * @param handle handle to a TurboJPEG instance that has been initialized for * compression * * @param iccBuf pointer to a byte buffer containing an ICC profile. A copy is * made of the ICC profile, so this buffer can be freed or reused as soon as * this function returns. Setting this parameter to NULL or setting `iccSize` * to 0 removes any ICC profile that was previously associated with the * TurboJPEG instance. * * @param iccSize size of the ICC profile (in bytes.) Setting this parameter * to 0 or setting `iccBuf` to NULL removes any ICC profile that was previously * associated with the TurboJPEG instance. * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr().) */ DLLEXPORT int tj3SetICCProfile(tjhandle handle, unsigned char *iccBuf, size_t iccSize); /** * Compress a packed-pixel RGB, grayscale, or CMYK image with 2 to 8 bits of * data precision per sample into a JPEG image with the same data precision. * * @param handle handle to a TurboJPEG instance that has been initialized for * compression * * @param srcBuf pointer to a buffer containing a packed-pixel RGB, grayscale, * or CMYK source image to be compressed. This buffer should normally be * `pitch * height` samples in size. However, you can also use this parameter * to compress from a specific region of a larger buffer. The data precision * of the source image (from 2 to 8 bits per sample) can be specified using * #TJPARAM_PRECISION and defaults to 8 if #TJPARAM_PRECISION is unset or out * of range. * * @param width width (in pixels) of the source image * * @param pitch samples per row in the source image. Normally this should be * width * #tjPixelSize[pixelFormat], if the image is unpadded. * (Setting this parameter to 0 is the equivalent of setting it to * width * #tjPixelSize[pixelFormat].) However, you can also use this * parameter to specify the row alignment/padding of the source image, to skip * rows, or to compress from a specific region of a larger buffer. * * @param height height (in pixels) of the source image * * @param pixelFormat pixel format of the source image (see @ref TJPF * "Pixel formats".) * * @param jpegBuf address of a pointer to a byte buffer that will receive the * JPEG image. TurboJPEG has the ability to reallocate the JPEG buffer to * accommodate the size of the JPEG image. Thus, you can choose to: * -# pre-allocate the JPEG buffer with an arbitrary size using #tj3Alloc() and * let TurboJPEG grow the buffer as needed, * -# set `*jpegBuf` to NULL to tell TurboJPEG to allocate the buffer for you, * or * -# pre-allocate the buffer to a "worst case" size determined by calling * #tj3JPEGBufSize() and adding the return value to the size of the ICC profile * (if any) that was previously associated with the TurboJPEG instance (see * #tj3SetICCProfile().) This should ensure that the buffer never has to be * re-allocated. (Setting #TJPARAM_NOREALLOC guarantees that it won't be.) * . * Unless you have set #TJPARAM_NOREALLOC, you should always check `*jpegBuf` * upon return from this function, as it may have changed. * * @param jpegSize pointer to a size_t variable that holds the size of the JPEG * buffer. If `*jpegBuf` points to a pre-allocated buffer, then `*jpegSize` * should be set to the size of the buffer. Otherwise, `*jpegSize` is * ignored. If `*jpegBuf` points to a JPEG buffer that is being reused from a * previous call to one of the JPEG compression functions, then `*jpegSize` is * also ignored. Upon return, `*jpegSize` will contain the size of the JPEG * image (in bytes.) * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3Compress8(tjhandle handle, const unsigned char *srcBuf, int width, int pitch, int height, int pixelFormat, unsigned char **jpegBuf, size_t *jpegSize); /** * Compress a packed-pixel RGB, grayscale, or CMYK image with 9 to 12 bits of * data precision per sample into a JPEG image with the same data precision. * * @param handle handle to a TurboJPEG instance that has been initialized for * compression * * @param srcBuf pointer to a buffer containing a packed-pixel RGB, grayscale, * or CMYK source image to be compressed. This buffer should normally be * `pitch * height` samples in size. However, you can also use this parameter * to compress from a specific region of a larger buffer. The data precision * of the source image (from 9 to 12 bits per sample) can be specified using * #TJPARAM_PRECISION and defaults to 12 if #TJPARAM_PRECISION is unset or out * of range. * * @param width width (in pixels) of the source image * * @param pitch samples per row in the source image. Normally this should be * width * #tjPixelSize[pixelFormat], if the image is unpadded. * (Setting this parameter to 0 is the equivalent of setting it to * width * #tjPixelSize[pixelFormat].) However, you can also use this * parameter to specify the row alignment/padding of the source image, to skip * rows, or to compress from a specific region of a larger buffer. * * @param height height (in pixels) of the source image * * @param pixelFormat pixel format of the source image (see @ref TJPF * "Pixel formats".) * * @param jpegBuf address of a pointer to a byte buffer that will receive the * JPEG image. TurboJPEG has the ability to reallocate the JPEG buffer to * accommodate the size of the JPEG image. Thus, you can choose to: * -# pre-allocate the JPEG buffer with an arbitrary size using #tj3Alloc() and * let TurboJPEG grow the buffer as needed, * -# set `*jpegBuf` to NULL to tell TurboJPEG to allocate the buffer for you, * or * -# pre-allocate the buffer to a "worst case" size determined by calling * #tj3JPEGBufSize() and adding the return value to the size of the ICC profile * (if any) that was previously associated with the TurboJPEG instance (see * #tj3SetICCProfile().) This should ensure that the buffer never has to be * re-allocated. (Setting #TJPARAM_NOREALLOC guarantees that it won't be.) * . * Unless you have set #TJPARAM_NOREALLOC, you should always check `*jpegBuf` * upon return from this function, as it may have changed. * * @param jpegSize pointer to a size_t variable that holds the size of the JPEG * buffer. If `*jpegBuf` points to a pre-allocated buffer, then `*jpegSize` * should be set to the size of the buffer. Otherwise, `*jpegSize` is * ignored. If `*jpegBuf` points to a JPEG buffer that is being reused from a * previous call to one of the JPEG compression functions, then `*jpegSize` is * also ignored. Upon return, `*jpegSize` will contain the size of the JPEG * image (in bytes.) * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3Compress12(tjhandle handle, const short *srcBuf, int width, int pitch, int height, int pixelFormat, unsigned char **jpegBuf, size_t *jpegSize); /** * Compress a packed-pixel RGB, grayscale, or CMYK image with 13 to 16 bits of * data precision per sample into a lossless JPEG image with the same data * precision. * * @param handle handle to a TurboJPEG instance that has been initialized for * compression * * @param srcBuf pointer to a buffer containing a packed-pixel RGB, grayscale, * or CMYK source image to be compressed. This buffer should normally be * `pitch * height` samples in size. However, you can also use this parameter * to compress from a specific region of a larger buffer. The data precision * of the source image (from 13 to 16 bits per sample) can be specified using * #TJPARAM_PRECISION and defaults to 16 if #TJPARAM_PRECISION is unset or out * of range. * * @param width width (in pixels) of the source image * * @param pitch samples per row in the source image. Normally this should be * width * #tjPixelSize[pixelFormat], if the image is unpadded. * (Setting this parameter to 0 is the equivalent of setting it to * width * #tjPixelSize[pixelFormat].) However, you can also use this * parameter to specify the row alignment/padding of the source image, to skip * rows, or to compress from a specific region of a larger buffer. * * @param height height (in pixels) of the source image * * @param pixelFormat pixel format of the source image (see @ref TJPF * "Pixel formats".) * * @param jpegBuf address of a pointer to a byte buffer that will receive the * JPEG image. TurboJPEG has the ability to reallocate the JPEG buffer to * accommodate the size of the JPEG image. Thus, you can choose to: * -# pre-allocate the JPEG buffer with an arbitrary size using #tj3Alloc() and * let TurboJPEG grow the buffer as needed, * -# set `*jpegBuf` to NULL to tell TurboJPEG to allocate the buffer for you, * or * -# pre-allocate the buffer to a "worst case" size determined by calling * #tj3JPEGBufSize() and adding the return value to the size of the ICC profile * (if any) that was previously associated with the TurboJPEG instance (see * #tj3SetICCProfile().) This should ensure that the buffer never has to be * re-allocated. (Setting #TJPARAM_NOREALLOC guarantees that it won't be.) * . * Unless you have set #TJPARAM_NOREALLOC, you should always check `*jpegBuf` * upon return from this function, as it may have changed. * * @param jpegSize pointer to a size_t variable that holds the size of the JPEG * buffer. If `*jpegBuf` points to a pre-allocated buffer, then `*jpegSize` * should be set to the size of the buffer. Otherwise, `*jpegSize` is * ignored. If `*jpegBuf` points to a JPEG buffer that is being reused from a * previous call to one of the JPEG compression functions, then `*jpegSize` is * also ignored. Upon return, `*jpegSize` will contain the size of the JPEG * image (in bytes.) * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3Compress16(tjhandle handle, const unsigned short *srcBuf, int width, int pitch, int height, int pixelFormat, unsigned char **jpegBuf, size_t *jpegSize); /** * Compress a set of 8-bit-per-sample Y, U (Cb), and V (Cr) image planes into * an 8-bit-per-sample lossy @ref TJCS_YCbCr "YCbCr" or * @ref TJCS_GRAY "grayscale" JPEG image. * * @param handle handle to a TurboJPEG instance that has been initialized for * compression * * @param srcPlanes an array of pointers to Y, U (Cb), and V (Cr) image planes * (or just a Y plane, if compressing a grayscale image) that contain a YUV * source image to be compressed. These planes can be contiguous or * non-contiguous in memory. The size of each plane should match the value * returned by #tj3YUVPlaneSize() for the given image width, height, strides, * and level of chrominance subsampling (see #TJPARAM_SUBSAMP.) Refer to * @ref YUVnotes "YUV Image Format Notes" for more details. * * @param width width (in pixels) of the source image. If the width is not an * even multiple of the iMCU width (see #tjMCUWidth), then an intermediate * buffer copy will be performed. * * @param strides an array of integers, each specifying the number of bytes per * row in the corresponding plane of the YUV source image. Setting the stride * for any plane to 0 is the same as setting it to the plane width (see * @ref YUVnotes "YUV Image Format Notes".) If `strides` is NULL, then the * strides for all planes will be set to their respective plane widths. You * can adjust the strides in order to specify an arbitrary amount of row * padding in each plane or to create a JPEG image from a subregion of a larger * planar YUV image. * * @param height height (in pixels) of the source image. If the height is not * an even multiple of the iMCU height (see #tjMCUHeight), then an intermediate * buffer copy will be performed. * * @param jpegBuf address of a pointer to a byte buffer that will receive the * JPEG image. TurboJPEG has the ability to reallocate the JPEG buffer to * accommodate the size of the JPEG image. Thus, you can choose to: * -# pre-allocate the JPEG buffer with an arbitrary size using #tj3Alloc() and * let TurboJPEG grow the buffer as needed, * -# set `*jpegBuf` to NULL to tell TurboJPEG to allocate the buffer for you, * or * -# pre-allocate the buffer to a "worst case" size determined by calling * #tj3JPEGBufSize() and adding the return value to the size of the ICC profile * (if any) that was previously associated with the TurboJPEG instance (see * #tj3SetICCProfile().) This should ensure that the buffer never has to be * re-allocated. (Setting #TJPARAM_NOREALLOC guarantees that it won't be.) * . * Unless you have set #TJPARAM_NOREALLOC, you should always check `*jpegBuf` * upon return from this function, as it may have changed. * * @param jpegSize pointer to a size_t variable that holds the size of the JPEG * buffer. If `*jpegBuf` points to a pre-allocated buffer, then `*jpegSize` * should be set to the size of the buffer. Otherwise, `*jpegSize` is * ignored. If `*jpegBuf` points to a JPEG buffer that is being reused from a * previous call to one of the JPEG compression functions, then `*jpegSize` is * also ignored. Upon return, `*jpegSize` will contain the size of the JPEG * image (in bytes.) * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3CompressFromYUVPlanes8(tjhandle handle, const unsigned char * const *srcPlanes, int width, const int *strides, int height, unsigned char **jpegBuf, size_t *jpegSize); /** * Compress an 8-bit-per-sample unified planar YUV image into an * 8-bit-per-sample lossy @ref TJCS_YCbCr "YCbCr" or @ref TJCS_GRAY "grayscale" * JPEG image. * * @param handle handle to a TurboJPEG instance that has been initialized for * compression * * @param srcBuf pointer to a buffer containing a unified planar YUV source * image to be compressed. The size of this buffer should match the value * returned by #tj3YUVBufSize() for the given image width, height, row * alignment, and level of chrominance subsampling (see #TJPARAM_SUBSAMP.) The * Y, U (Cb), and V (Cr) image planes should be stored sequentially in the * buffer. (Refer to @ref YUVnotes "YUV Image Format Notes".) * * @param width width (in pixels) of the source image. If the width is not an * even multiple of the iMCU width (see #tjMCUWidth), then an intermediate * buffer copy will be performed. * * @param align row alignment (in bytes) of the source image (must be a power * of 2.) Setting this parameter to n indicates that each row in each plane of * the source image is padded to the nearest multiple of n bytes * (1 = unpadded.) * * @param height height (in pixels) of the source image. If the height is not * an even multiple of the iMCU height (see #tjMCUHeight), then an intermediate * buffer copy will be performed. * * @param jpegBuf address of a pointer to a byte buffer that will receive the * JPEG image. TurboJPEG has the ability to reallocate the JPEG buffer to * accommodate the size of the JPEG image. Thus, you can choose to: * -# pre-allocate the JPEG buffer with an arbitrary size using #tj3Alloc() and * let TurboJPEG grow the buffer as needed, * -# set `*jpegBuf` to NULL to tell TurboJPEG to allocate the buffer for you, * or * -# pre-allocate the buffer to a "worst case" size determined by calling * #tj3JPEGBufSize() and adding the return value to the size of the ICC profile * (if any) that was previously associated with the TurboJPEG instance (see * #tj3SetICCProfile().) This should ensure that the buffer never has to be * re-allocated. (Setting #TJPARAM_NOREALLOC guarantees that it won't be.) * . * Unless you have set #TJPARAM_NOREALLOC, you should always check `*jpegBuf` * upon return from this function, as it may have changed. * * @param jpegSize pointer to a size_t variable that holds the size of the JPEG * buffer. If `*jpegBuf` points to a pre-allocated buffer, then `*jpegSize` * should be set to the size of the buffer. Otherwise, `*jpegSize` is * ignored. If `*jpegBuf` points to a JPEG buffer that is being reused from a * previous call to one of the JPEG compression functions, then `*jpegSize` is * also ignored. Upon return, `*jpegSize` will contain the size of the JPEG * image (in bytes.) * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3CompressFromYUV8(tjhandle handle, const unsigned char *srcBuf, int width, int align, int height, unsigned char **jpegBuf, size_t *jpegSize); /** * Encode an 8-bit-per-sample packed-pixel RGB or grayscale image into separate * 8-bit-per-sample Y, U (Cb), and V (Cr) image planes. This function performs * color conversion and downsampling (which are accelerated in the * libjpeg-turbo implementation) but does not execute any of the other steps in * the JPEG compression process. * * @param handle handle to a TurboJPEG instance that has been initialized for * compression * * @param srcBuf pointer to a buffer containing a packed-pixel RGB or grayscale * source image to be encoded. This buffer should normally be `pitch * height` * bytes in size. However, you can also use this parameter to encode from a * specific region of a larger buffer. * * * @param width width (in pixels) of the source image * * @param pitch bytes per row in the source image. Normally this should be * width * #tjPixelSize[pixelFormat], if the image is unpadded. * (Setting this parameter to 0 is the equivalent of setting it to * width * #tjPixelSize[pixelFormat].) However, you can also use this * parameter to specify the row alignment/padding of the source image, to skip * rows, or to encode from a specific region of a larger packed-pixel image. * * @param height height (in pixels) of the source image * * @param pixelFormat pixel format of the source image (see @ref TJPF * "Pixel formats".) * * @param dstPlanes an array of pointers to Y, U (Cb), and V (Cr) image planes * (or just a Y plane, if generating a grayscale image) that will receive the * encoded image. These planes can be contiguous or non-contiguous in memory. * Use #tj3YUVPlaneSize() to determine the appropriate size for each plane * based on the image width, height, strides, and level of chrominance * subsampling (see #TJPARAM_SUBSAMP.) Refer to @ref YUVnotes * "YUV Image Format Notes" for more details. * * @param strides an array of integers, each specifying the number of bytes per * row in the corresponding plane of the YUV image. Setting the stride for any * plane to 0 is the same as setting it to the plane width (see @ref YUVnotes * "YUV Image Format Notes".) If `strides` is NULL, then the strides for all * planes will be set to their respective plane widths. You can adjust the * strides in order to add an arbitrary amount of row padding to each plane or * to encode an RGB or grayscale image into a subregion of a larger planar YUV * image. * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3EncodeYUVPlanes8(tjhandle handle, const unsigned char *srcBuf, int width, int pitch, int height, int pixelFormat, unsigned char **dstPlanes, int *strides); /** * Encode an 8-bit-per-sample packed-pixel RGB or grayscale image into an * 8-bit-per-sample unified planar YUV image. This function performs color * conversion and downsampling (which are accelerated in the libjpeg-turbo * implementation) but does not execute any of the other steps in the JPEG * compression process. * * @param handle handle to a TurboJPEG instance that has been initialized for * compression * * @param srcBuf pointer to a buffer containing a packed-pixel RGB or grayscale * source image to be encoded. This buffer should normally be `pitch * height` * bytes in size. However, you can also use this parameter to encode from a * specific region of a larger buffer. * * @param width width (in pixels) of the source image * * @param pitch bytes per row in the source image. Normally this should be * width * #tjPixelSize[pixelFormat], if the image is unpadded. * (Setting this parameter to 0 is the equivalent of setting it to * width * #tjPixelSize[pixelFormat].) However, you can also use this * parameter to specify the row alignment/padding of the source image, to skip * rows, or to encode from a specific region of a larger packed-pixel image. * * @param height height (in pixels) of the source image * * @param pixelFormat pixel format of the source image (see @ref TJPF * "Pixel formats".) * * @param dstBuf pointer to a buffer that will receive the unified planar YUV * image. Use #tj3YUVBufSize() to determine the appropriate size for this * buffer based on the image width, height, row alignment, and level of * chrominance subsampling (see #TJPARAM_SUBSAMP.) The Y, U (Cb), and V (Cr) * image planes will be stored sequentially in the buffer. (Refer to * @ref YUVnotes "YUV Image Format Notes".) * * @param align row alignment (in bytes) of the YUV image (must be a power of * 2.) Setting this parameter to n will cause each row in each plane of the * YUV image to be padded to the nearest multiple of n bytes (1 = unpadded.) * To generate images suitable for X Video, `align` should be set to 4. * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3EncodeYUV8(tjhandle handle, const unsigned char *srcBuf, int width, int pitch, int height, int pixelFormat, unsigned char *dstBuf, int align); /** * Retrieve information about a JPEG image without decompressing it, or prime * the decompressor with quantization and Huffman tables. If a JPEG image is * passed to this function, then the @ref TJPARAM "parameters" that describe * the JPEG image will be set when the function returns. If a JPEG image is * passed to this function and #TJPARAM_SAVEMARKERS is set to `2` or `4`, then * the ICC profile (if any) will be extracted from the JPEG image. * (#tj3GetICCProfile() can then be used to retrieve the profile.) * * @param handle handle to a TurboJPEG instance that has been initialized for * decompression * * @param jpegBuf pointer to a byte buffer containing a JPEG image or an * "abbreviated table specification" (AKA "tables-only") datastream. Passing a * tables-only datastream to this function primes the decompressor with * quantization and Huffman tables that can be used when decompressing * subsequent "abbreviated image" datastreams. This is useful, for instance, * when decompressing video streams in which all frames share the same * quantization and Huffman tables. * * @param jpegSize size of the JPEG image or tables-only datastream (in bytes) * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3DecompressHeader(tjhandle handle, const unsigned char *jpegBuf, size_t jpegSize); /** * Retrieve the ICC (International Color Consortium) color management profile * (if any) that was previously extracted from a JPEG image. * * @note To extract the ICC profile from a JPEG image, call * #tj3DecompressHeader() with #TJPARAM_SAVEMARKERS set to `2` or `4`. Once * the ICC profile is retrieved, it must be re-extracted before it can be * retrieved again. * * @param handle handle to a TurboJPEG instance that has been initialized for * decompression * * @param iccBuf address of a pointer to a byte buffer. Upon return: * - If `iccBuf` is not NULL and there is an ICC profile to retrieve, then * `*iccBuf` will point to a byte buffer containing the ICC profile. This * buffer should be freed using #tj3Free(). * - If `iccBuf` is not NULL and there is no ICC profile to retrieve, then * `*iccBuf` will be NULL. * - If `iccBuf` is NULL, then only the ICC profile size will be retrieved, and * the ICC profile can be retrieved later. * * @param iccSize address of a size_t variable. Upon return, the variable will * contain the ICC profile size (or 0 if there is no ICC profile to retrieve.) * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3GetICCProfile(tjhandle handle, unsigned char **iccBuf, size_t *iccSize); /** * Returns a list of fractional scaling factors that the JPEG decompressor * supports. * * @param numScalingFactors pointer to an integer variable that will receive * the number of elements in the list * * @return a pointer to a list of fractional scaling factors, or NULL if an * error is encountered (see #tj3GetErrorStr().) */ DLLEXPORT tjscalingfactor *tj3GetScalingFactors(int *numScalingFactors); /** * Set the scaling factor for subsequent lossy decompression operations. * * @param handle handle to a TurboJPEG instance that has been initialized for * decompression * * @param scalingFactor #tjscalingfactor structure that specifies a fractional * scaling factor that the decompressor supports (see #tj3GetScalingFactors()), * or #TJUNSCALED for no scaling. Decompression scaling is a function * of the IDCT algorithm, so scaling factors are generally limited to multiples * of 1/8. If the entire JPEG image will be decompressed, then the width and * height of the scaled destination image can be determined by calling * #TJSCALED() with the JPEG width and height (see #TJPARAM_JPEGWIDTH and * #TJPARAM_JPEGHEIGHT) and the specified scaling factor. When decompressing * into a planar YUV image, an intermediate buffer copy will be performed if * the width or height of the scaled destination image is not an even multiple * of the iMCU size (see #tjMCUWidth and #tjMCUHeight.) Note that * decompression scaling is not available (and the specified scaling factor is * ignored) when decompressing lossless JPEG images (see #TJPARAM_LOSSLESS), * since the IDCT algorithm is not used with those images. Note also that * #TJPARAM_FASTDCT is ignored when decompression scaling is enabled. * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr().) */ DLLEXPORT int tj3SetScalingFactor(tjhandle handle, tjscalingfactor scalingFactor); /** * Set the cropping region for partially decompressing a lossy JPEG image into * a packed-pixel image * * @param handle handle to a TurboJPEG instance that has been initialized for * decompression * * @param croppingRegion #tjregion structure that specifies a subregion of the * JPEG image to decompress, or #TJUNCROPPED for no cropping. The * left boundary of the cropping region must be evenly divisible by the scaled * iMCU width-- #TJSCALED(#tjMCUWidth[subsamp], scalingFactor), where * `subsamp` is the level of chrominance subsampling in the JPEG image (see * #TJPARAM_SUBSAMP) and `scalingFactor` is the decompression scaling factor * (see #tj3SetScalingFactor().) The cropping region should be specified * relative to the scaled image dimensions. Unless `croppingRegion` is * #TJUNCROPPED, the JPEG header must be read (see * #tj3DecompressHeader()) prior to calling this function. * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr().) */ DLLEXPORT int tj3SetCroppingRegion(tjhandle handle, tjregion croppingRegion); /** * Decompress a JPEG image with 2 to 8 bits of data precision per sample into a * packed-pixel RGB, grayscale, or CMYK image with the same data precision. * The @ref TJPARAM "parameters" that describe the JPEG image will be set when * this function returns. * * @param handle handle to a TurboJPEG instance that has been initialized for * decompression * * @param jpegBuf pointer to a byte buffer containing the JPEG image to * decompress * * @param jpegSize size of the JPEG image (in bytes) * * @param dstBuf pointer to a buffer that will receive the packed-pixel * decompressed image. This buffer should normally be * `pitch * destinationHeight` samples in size. However, you can also use this * parameter to decompress into a specific region of a larger buffer. NOTE: * If the JPEG image is lossy, then `destinationHeight` is either the scaled * JPEG height (see #TJSCALED(), #TJPARAM_JPEGHEIGHT, and * #tj3SetScalingFactor()) or the height of the cropping region (see * #tj3SetCroppingRegion().) If the JPEG image is lossless, then * `destinationHeight` is the JPEG height. * * @param pitch samples per row in the destination image. Normally this should * be set to destinationWidth * #tjPixelSize[pixelFormat], if the * destination image should be unpadded. (Setting this parameter to 0 is the * equivalent of setting it to * destinationWidth * #tjPixelSize[pixelFormat].) However, you can * also use this parameter to specify the row alignment/padding of the * destination image, to skip rows, or to decompress into a specific region of * a larger buffer. NOTE: If the JPEG image is lossy, then `destinationWidth` * is either the scaled JPEG width (see #TJSCALED(), #TJPARAM_JPEGWIDTH, and * #tj3SetScalingFactor()) or the width of the cropping region (see * #tj3SetCroppingRegion().) If the JPEG image is lossless, then * `destinationWidth` is the JPEG width. * * @param pixelFormat pixel format of the destination image (see @ref * TJPF "Pixel formats".) * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3Decompress8(tjhandle handle, const unsigned char *jpegBuf, size_t jpegSize, unsigned char *dstBuf, int pitch, int pixelFormat); /** * Decompress a JPEG image with 9 to 12 bits of data precision per sample into * a packed-pixel RGB, grayscale, or CMYK image with the same data precision. * * \details \copydetails tj3Decompress8() */ DLLEXPORT int tj3Decompress12(tjhandle handle, const unsigned char *jpegBuf, size_t jpegSize, short *dstBuf, int pitch, int pixelFormat); /** * Decompress a lossless JPEG image with 13 to 16 bits of data precision per * sample into a packed-pixel RGB, grayscale, or CMYK image with the same * data precision. * * \details \copydetails tj3Decompress8() */ DLLEXPORT int tj3Decompress16(tjhandle handle, const unsigned char *jpegBuf, size_t jpegSize, unsigned short *dstBuf, int pitch, int pixelFormat); /** * Decompress an 8-bit-per-sample lossy JPEG image into separate * 8-bit-per-sample Y, U (Cb), and V (Cr) image planes. This function performs * JPEG decompression but leaves out the color conversion step, so a planar YUV * image is generated instead of a packed-pixel image. The * @ref TJPARAM "parameters" that describe the JPEG image will be set when this * function returns. * * @param handle handle to a TurboJPEG instance that has been initialized for * decompression * * @param jpegBuf pointer to a byte buffer containing the JPEG image to * decompress * * @param jpegSize size of the JPEG image (in bytes) * * @param dstPlanes an array of pointers to Y, U (Cb), and V (Cr) image planes * (or just a Y plane, if decompressing a grayscale image) that will receive * the decompressed image. These planes can be contiguous or non-contiguous in * memory. Use #tj3YUVPlaneSize() to determine the appropriate size for each * plane based on the scaled JPEG width and height (see #TJSCALED(), * #TJPARAM_JPEGWIDTH, #TJPARAM_JPEGHEIGHT, and #tj3SetScalingFactor()), * strides, and level of chrominance subsampling (see #TJPARAM_SUBSAMP.) Refer * to @ref YUVnotes "YUV Image Format Notes" for more details. * * @param strides an array of integers, each specifying the number of bytes per * row in the corresponding plane of the YUV image. Setting the stride for any * plane to 0 is the same as setting it to the scaled plane width (see * @ref YUVnotes "YUV Image Format Notes".) If `strides` is NULL, then the * strides for all planes will be set to their respective scaled plane widths. * You can adjust the strides in order to add an arbitrary amount of row * padding to each plane or to decompress the JPEG image into a subregion of a * larger planar YUV image. * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3DecompressToYUVPlanes8(tjhandle handle, const unsigned char *jpegBuf, size_t jpegSize, unsigned char **dstPlanes, int *strides); /** * Decompress an 8-bit-per-sample lossy JPEG image into an 8-bit-per-sample * unified planar YUV image. This function performs JPEG decompression but * leaves out the color conversion step, so a planar YUV image is generated * instead of a packed-pixel image. The @ref TJPARAM "parameters" that * describe the JPEG image will be set when this function returns. * * @param handle handle to a TurboJPEG instance that has been initialized for * decompression * * @param jpegBuf pointer to a byte buffer containing the JPEG image to * decompress * * @param jpegSize size of the JPEG image (in bytes) * * @param dstBuf pointer to a buffer that will receive the unified planar YUV * decompressed image. Use #tj3YUVBufSize() to determine the appropriate size * for this buffer based on the scaled JPEG width and height (see #TJSCALED(), * #TJPARAM_JPEGWIDTH, #TJPARAM_JPEGHEIGHT, and #tj3SetScalingFactor()), row * alignment, and level of chrominance subsampling (see #TJPARAM_SUBSAMP.) The * Y, U (Cb), and V (Cr) image planes will be stored sequentially in the * buffer. (Refer to @ref YUVnotes "YUV Image Format Notes".) * * @param align row alignment (in bytes) of the YUV image (must be a power of * 2.) Setting this parameter to n will cause each row in each plane of the * YUV image to be padded to the nearest multiple of n bytes (1 = unpadded.) * To generate images suitable for X Video, `align` should be set to 4. * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3DecompressToYUV8(tjhandle handle, const unsigned char *jpegBuf, size_t jpegSize, unsigned char *dstBuf, int align); /** * Decode a set of 8-bit-per-sample Y, U (Cb), and V (Cr) image planes into an * 8-bit-per-sample packed-pixel RGB or grayscale image. This function * performs color conversion (which is accelerated in the libjpeg-turbo * implementation) but does not execute any of the other steps in the JPEG * decompression process. * * @param handle handle to a TurboJPEG instance that has been initialized for * decompression * * @param srcPlanes an array of pointers to Y, U (Cb), and V (Cr) image planes * (or just a Y plane, if decoding a grayscale image) that contain a YUV image * to be decoded. These planes can be contiguous or non-contiguous in memory. * The size of each plane should match the value returned by #tj3YUVPlaneSize() * for the given image width, height, strides, and level of chrominance * subsampling (see #TJPARAM_SUBSAMP.) Refer to @ref YUVnotes * "YUV Image Format Notes" for more details. * * @param strides an array of integers, each specifying the number of bytes per * row in the corresponding plane of the YUV source image. Setting the stride * for any plane to 0 is the same as setting it to the plane width (see * @ref YUVnotes "YUV Image Format Notes".) If `strides` is NULL, then the * strides for all planes will be set to their respective plane widths. You * can adjust the strides in order to specify an arbitrary amount of row * padding in each plane or to decode a subregion of a larger planar YUV image. * * @param dstBuf pointer to a buffer that will receive the packed-pixel decoded * image. This buffer should normally be `pitch * height` bytes in size. * However, you can also use this parameter to decode into a specific region of * a larger buffer. * * @param width width (in pixels) of the source and destination images * * @param pitch bytes per row in the destination image. Normally this should * be set to width * #tjPixelSize[pixelFormat], if the destination * image should be unpadded. (Setting this parameter to 0 is the equivalent of * setting it to width * #tjPixelSize[pixelFormat].) However, you can * also use this parameter to specify the row alignment/padding of the * destination image, to skip rows, or to decode into a specific region of a * larger buffer. * * @param height height (in pixels) of the source and destination images * * @param pixelFormat pixel format of the destination image (see @ref TJPF * "Pixel formats".) * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3DecodeYUVPlanes8(tjhandle handle, const unsigned char * const *srcPlanes, const int *strides, unsigned char *dstBuf, int width, int pitch, int height, int pixelFormat); /** * Decode an 8-bit-per-sample unified planar YUV image into an 8-bit-per-sample * packed-pixel RGB or grayscale image. This function performs color * conversion (which is accelerated in the libjpeg-turbo implementation) but * does not execute any of the other steps in the JPEG decompression process. * * @param handle handle to a TurboJPEG instance that has been initialized for * decompression * * @param srcBuf pointer to a buffer containing a unified planar YUV source * image to be decoded. The size of this buffer should match the value * returned by #tj3YUVBufSize() for the given image width, height, row * alignment, and level of chrominance subsampling (see #TJPARAM_SUBSAMP.) The * Y, U (Cb), and V (Cr) image planes should be stored sequentially in the * source buffer. (Refer to @ref YUVnotes "YUV Image Format Notes".) * * @param align row alignment (in bytes) of the YUV source image (must be a * power of 2.) Setting this parameter to n indicates that each row in each * plane of the YUV source image is padded to the nearest multiple of n bytes * (1 = unpadded.) * * @param dstBuf pointer to a buffer that will receive the packed-pixel decoded * image. This buffer should normally be `pitch * height` bytes in size. * However, you can also use this parameter to decode into a specific region of * a larger buffer. * * @param width width (in pixels) of the source and destination images * * @param pitch bytes per row in the destination image. Normally this should * be set to width * #tjPixelSize[pixelFormat], if the destination * image should be unpadded. (Setting this parameter to 0 is the equivalent of * setting it to width * #tjPixelSize[pixelFormat].) However, you can * also use this parameter to specify the row alignment/padding of the * destination image, to skip rows, or to decode into a specific region of a * larger buffer. * * @param height height (in pixels) of the source and destination images * * @param pixelFormat pixel format of the destination image (see @ref TJPF * "Pixel formats".) * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3DecodeYUV8(tjhandle handle, const unsigned char *srcBuf, int align, unsigned char *dstBuf, int width, int pitch, int height, int pixelFormat); /** * The maximum size of the buffer (in bytes) required to hold a JPEG image * transformed with the given transform parameters and/or cropping region. * This function is a wrapper for #tj3JPEGBufSize() that takes into account * cropping, transposition of the width and height (which affects the * destination image dimensions and level of chrominance subsampling), * grayscale conversion, and the ICC profile (if any) that was previously * associated with the TurboJPEG instance (see #tj3SetICCProfile()) or * extracted from the source image (see #tj3GetICCProfile() and * #TJPARAM_SAVEMARKERS.) The JPEG header must be read (see * tj3DecompressHeader()) prior to calling this function. * * @param handle handle to a TurboJPEG instance that has been initialized for * lossless transformation * * @param transform pointer to a #tjtransform structure that specifies the * transform parameters and/or cropping region for the JPEG image. * * @return the maximum size of the buffer (in bytes) required to hold the * transformed image, or 0 if an error occurred (see #tj3GetErrorStr() and * #tj3GetErrorCode().) */ DLLEXPORT size_t tj3TransformBufSize(tjhandle handle, const tjtransform *transform); /** * Losslessly transform a JPEG image into another JPEG image. Lossless * transforms work by moving the raw DCT coefficients from one JPEG image * structure to another without altering the values of the coefficients. While * this is typically faster than decompressing the image, transforming it, and * re-compressing it, lossless transforms are not free. Each lossless * transform requires reading and performing entropy decoding on all of the * coefficients in the source image, regardless of the size of the destination * image. Thus, this function provides a means of generating multiple * transformed images from the same source or applying multiple transformations * simultaneously, in order to eliminate the need to read the source * coefficients multiple times. * * @param handle handle to a TurboJPEG instance that has been initialized for * lossless transformation * * @param jpegBuf pointer to a byte buffer containing the JPEG source image to * transform * * @param jpegSize size of the JPEG source image (in bytes) * * @param n the number of transformed JPEG images to generate * * @param dstBufs pointer to an array of n byte buffers. `dstBufs[i]` will * receive a JPEG image that has been transformed using the parameters in * `transforms[i]`. TurboJPEG has the ability to reallocate the JPEG * destination buffer to accommodate the size of the transformed JPEG image. * Thus, you can choose to: * -# pre-allocate the JPEG destination buffer with an arbitrary size using * #tj3Alloc() and let TurboJPEG grow the buffer as needed, * -# set `dstBufs[i]` to NULL to tell TurboJPEG to allocate the buffer for * you, or * -# pre-allocate the buffer to a "worst case" size determined by calling * #tj3TransformBufSize(). Under normal circumstances, this should ensure that * the buffer never has to be re-allocated. (Setting #TJPARAM_NOREALLOC * guarantees that it won't be. However, if the source image has a large * amount of embedded Exif data, then the transformed JPEG image may be larger * than the worst-case size. #TJPARAM_NOREALLOC cannot be used in that case * unless the embedded data is discarded using #TJXOPT_COPYNONE or * #TJPARAM_SAVEMARKERS.) * . * Unless you have set #TJPARAM_NOREALLOC, you should always check `dstBufs[i]` * upon return from this function, as it may have changed. * * @param dstSizes pointer to an array of n size_t variables that will receive * the actual sizes (in bytes) of each transformed JPEG image. If `dstBufs[i]` * points to a pre-allocated buffer, then `dstSizes[i]` should be set to the * size of the buffer. Otherwise, `dstSizes[i]` is ignored. Upon return, * `dstSizes[i]` will contain the size of the transformed JPEG image (in * bytes.) * * @param transforms pointer to an array of n #tjtransform structures, each of * which specifies the transform parameters and/or cropping region for the * corresponding transformed JPEG image. * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3Transform(tjhandle handle, const unsigned char *jpegBuf, size_t jpegSize, int n, unsigned char **dstBufs, size_t *dstSizes, const tjtransform *transforms); /** * Load a packed-pixel image with 2 to 8 bits of data precision per sample from * disk into memory. * * @param handle handle to a TurboJPEG instance * * @param filename name of a file containing a packed-pixel image in Windows * BMP or PBMPLUS (PPM/PGM) format. Windows BMP files require 8-bit-per-sample * data precision. When loading a PBMPLUS file, the target data precision * (from 2 to 8 bits per sample) can be specified using #TJPARAM_PRECISION and * defaults to 8 if #TJPARAM_PRECISION is unset or out of range. If the data * precision of the PBMPLUS file does not match the target data precision, then * upconverting or downconverting will be performed. * * @param width pointer to an integer variable that will receive the width (in * pixels) of the packed-pixel image * * @param align row alignment (in samples) of the packed-pixel buffer to be * returned (must be a power of 2.) Setting this parameter to n will cause all * rows in the buffer to be padded to the nearest multiple of n samples * (1 = unpadded.) * * @param height pointer to an integer variable that will receive the height * (in pixels) of the packed-pixel image * * @param pixelFormat pointer to an integer variable that specifies or will * receive the pixel format of the packed-pixel buffer. The behavior of this * function varies depending on the value of `*pixelFormat` passed to the * function: * - @ref TJPF_UNKNOWN : The packed-pixel buffer returned by this function will * use the most optimal pixel format for the file type, and `*pixelFormat` will * contain the ID of that pixel format upon successful return from this * function. * - @ref TJPF_GRAY : Only PGM files and 8-bit-per-pixel BMP files with a * grayscale colormap can be loaded. * - @ref TJPF_CMYK : The RGB or grayscale pixels stored in the file will be * converted using a quick & dirty algorithm that is suitable only for testing * purposes. (Proper conversion between CMYK and other formats requires a * color management system.) * - Other @ref TJPF "pixel formats" : The packed-pixel buffer will use the * specified pixel format, and pixel format conversion will be performed if * necessary. * * @return a pointer to a newly-allocated buffer containing the packed-pixel * image, converted to the chosen pixel format and with the chosen row * alignment, or NULL if an error occurred (see #tj3GetErrorStr().) This * buffer should be freed using #tj3Free(). */ DLLEXPORT unsigned char *tj3LoadImage8(tjhandle handle, const char *filename, int *width, int align, int *height, int *pixelFormat); /** * Load a packed-pixel image with 9 to 12 bits of data precision per sample * from disk into memory. * * @param handle handle to a TurboJPEG instance * * @param filename name of a file containing a packed-pixel image in PBMPLUS * (PPM/PGM) format. The target data precision (from 9 to 12 bits per sample) * can be specified using #TJPARAM_PRECISION and defaults to 12 if * #TJPARAM_PRECISION is unset or out of range. If the data precision of the * PBMPLUS file does not match the target data precision, then upconverting or * downconverting will be performed. * * @param width pointer to an integer variable that will receive the width (in * pixels) of the packed-pixel image * * @param align row alignment (in samples) of the packed-pixel buffer to be * returned (must be a power of 2.) Setting this parameter to n will cause all * rows in the buffer to be padded to the nearest multiple of n samples * (1 = unpadded.) * * @param height pointer to an integer variable that will receive the height * (in pixels) of the packed-pixel image * * @param pixelFormat pointer to an integer variable that specifies or will * receive the pixel format of the packed-pixel buffer. The behavior of this * function will vary depending on the value of `*pixelFormat` passed to the * function: * - @ref TJPF_UNKNOWN : The packed-pixel buffer returned by this function will * use the most optimal pixel format for the file type, and `*pixelFormat` will * contain the ID of that pixel format upon successful return from this * function. * - @ref TJPF_GRAY : Only PGM files can be loaded. * - @ref TJPF_CMYK : The RGB or grayscale pixels stored in the file will be * converted using a quick & dirty algorithm that is suitable only for testing * purposes. (Proper conversion between CMYK and other formats requires a * color management system.) * - Other @ref TJPF "pixel formats" : The packed-pixel buffer will use the * specified pixel format, and pixel format conversion will be performed if * necessary. * * @return a pointer to a newly-allocated buffer containing the packed-pixel * image, converted to the chosen pixel format and with the chosen row * alignment, or NULL if an error occurred (see #tj3GetErrorStr().) This * buffer should be freed using #tj3Free(). */ DLLEXPORT short *tj3LoadImage12(tjhandle handle, const char *filename, int *width, int align, int *height, int *pixelFormat); /** * Load a packed-pixel image with 13 to 16 bits of data precision per sample * from disk into memory. * * @param handle handle to a TurboJPEG instance * * @param filename name of a file containing a packed-pixel image in PBMPLUS * (PPM/PGM) format. The target data precision (from 13 to 16 bits per sample) * can be specified using #TJPARAM_PRECISION and defaults to 16 if * #TJPARAM_PRECISION is unset or out of range. If the data precision of the * PBMPLUS file does not match the target data precision, then upconverting or * downconverting will be performed. * * @param width pointer to an integer variable that will receive the width (in * pixels) of the packed-pixel image * * @param align row alignment (in samples) of the packed-pixel buffer to be * returned (must be a power of 2.) Setting this parameter to n will cause all * rows in the buffer to be padded to the nearest multiple of n samples * (1 = unpadded.) * * @param height pointer to an integer variable that will receive the height * (in pixels) of the packed-pixel image * * @param pixelFormat pointer to an integer variable that specifies or will * receive the pixel format of the packed-pixel buffer. The behavior of this * function will vary depending on the value of `*pixelFormat` passed to the * function: * - @ref TJPF_UNKNOWN : The packed-pixel buffer returned by this function will * use the most optimal pixel format for the file type, and `*pixelFormat` will * contain the ID of that pixel format upon successful return from this * function. * - @ref TJPF_GRAY : Only PGM files can be loaded. * - @ref TJPF_CMYK : The RGB or grayscale pixels stored in the file will be * converted using a quick & dirty algorithm that is suitable only for testing * purposes. (Proper conversion between CMYK and other formats requires a * color management system.) * - Other @ref TJPF "pixel formats" : The packed-pixel buffer will use the * specified pixel format, and pixel format conversion will be performed if * necessary. * * @return a pointer to a newly-allocated buffer containing the packed-pixel * image, converted to the chosen pixel format and with the chosen row * alignment, or NULL if an error occurred (see #tj3GetErrorStr().) This * buffer should be freed using #tj3Free(). */ DLLEXPORT unsigned short *tj3LoadImage16(tjhandle handle, const char *filename, int *width, int align, int *height, int *pixelFormat); /** * Save a packed-pixel image with 2 to 8 bits of data precision per sample from * memory to disk. * * @param handle handle to a TurboJPEG instance * * @param filename name of a file to which to save the packed-pixel image. The * image will be stored in Windows BMP or PBMPLUS (PPM/PGM) format, depending * on the file extension. Windows BMP files require 8-bit-per-sample data * precision. When saving a PBMPLUS file, the source data precision (from 2 to * 8 bits per sample) can be specified using #TJPARAM_PRECISION and defaults to * 8 if #TJPARAM_PRECISION is unset or out of range. * * @param buffer pointer to a buffer containing a packed-pixel RGB, grayscale, * or CMYK image to be saved * * @param width width (in pixels) of the packed-pixel image * * @param pitch samples per row in the packed-pixel image. Setting this * parameter to 0 is the equivalent of setting it to * width * #tjPixelSize[pixelFormat]. * * @param height height (in pixels) of the packed-pixel image * * @param pixelFormat pixel format of the packed-pixel image (see @ref TJPF * "Pixel formats".) If this parameter is set to @ref TJPF_GRAY, then the * image will be stored in PGM or 8-bit-per-pixel (indexed color) BMP format. * Otherwise, the image will be stored in PPM or 24-bit-per-pixel BMP format. * If this parameter is set to @ref TJPF_CMYK, then the CMYK pixels will be * converted to RGB using a quick & dirty algorithm that is suitable only for * testing purposes. (Proper conversion between CMYK and other formats * requires a color management system.) * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr().) */ DLLEXPORT int tj3SaveImage8(tjhandle handle, const char *filename, const unsigned char *buffer, int width, int pitch, int height, int pixelFormat); /** * Save a packed-pixel image with 9 to 12 bits of data precision per sample * from memory to disk. * * @param handle handle to a TurboJPEG instance * * @param filename name of a file to which to save the packed-pixel image, * which will be stored in PBMPLUS (PPM/PGM) format. The source data precision * (from 9 to 12 bits per sample) can be specified using #TJPARAM_PRECISION and * defaults to 12 if #TJPARAM_PRECISION is unset or out of range. * * @param buffer pointer to a buffer containing a packed-pixel RGB, grayscale, * or CMYK image to be saved * * @param width width (in pixels) of the packed-pixel image * * @param pitch samples per row in the packed-pixel image. Setting this * parameter to 0 is the equivalent of setting it to * width * #tjPixelSize[pixelFormat]. * * @param height height (in pixels) of the packed-pixel image * * @param pixelFormat pixel format of the packed-pixel image (see @ref TJPF * "Pixel formats".) If this parameter is set to @ref TJPF_GRAY, then the * image will be stored in PGM format. Otherwise, the image will be stored in * PPM format. If this parameter is set to @ref TJPF_CMYK, then the CMYK * pixels will be converted to RGB using a quick & dirty algorithm that is * suitable only for testing purposes. (Proper conversion between CMYK and * other formats requires a color management system.) * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr().) */ DLLEXPORT int tj3SaveImage12(tjhandle handle, const char *filename, const short *buffer, int width, int pitch, int height, int pixelFormat); /** * Save a packed-pixel image with 13 to 16 bits of data precision per sample * from memory to disk. * * @param handle handle to a TurboJPEG instance * * @param filename name of a file to which to save the packed-pixel image, * which will be stored in PBMPLUS (PPM/PGM) format. The source data precision * (from 13 to 16 bits per sample) can be specified using #TJPARAM_PRECISION * and defaults to 16 if #TJPARAM_PRECISION is unset or out of range. * * @param buffer pointer to a buffer containing a packed-pixel RGB, grayscale, * or CMYK image to be saved * * @param width width (in pixels) of the packed-pixel image * * @param pitch samples per row in the packed-pixel image. Setting this * parameter to 0 is the equivalent of setting it to * width * #tjPixelSize[pixelFormat]. * * @param height height (in pixels) of the packed-pixel image * * @param pixelFormat pixel format of the packed-pixel image (see @ref TJPF * "Pixel formats".) If this parameter is set to @ref TJPF_GRAY, then the * image will be stored in PGM format. Otherwise, the image will be stored in * PPM format. If this parameter is set to @ref TJPF_CMYK, then the CMYK * pixels will be converted to RGB using a quick & dirty algorithm that is * suitable only for testing purposes. (Proper conversion between CMYK and * other formats requires a color management system.) * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr().) */ DLLEXPORT int tj3SaveImage16(tjhandle handle, const char *filename, const unsigned short *buffer, int width, int pitch, int height, int pixelFormat); /* Backward compatibility functions and macros (nothing to see here) */ /* TurboJPEG 1.0+ */ #define NUMSUBOPT TJ_NUMSAMP #define TJ_444 TJSAMP_444 #define TJ_422 TJSAMP_422 #define TJ_420 TJSAMP_420 #define TJ_411 TJSAMP_420 #define TJ_GRAYSCALE TJSAMP_GRAY #define TJ_BGR 1 #define TJ_BOTTOMUP TJFLAG_BOTTOMUP #define TJ_FORCEMMX TJFLAG_FORCEMMX #define TJ_FORCESSE TJFLAG_FORCESSE #define TJ_FORCESSE2 TJFLAG_FORCESSE2 #define TJ_ALPHAFIRST 64 #define TJ_FORCESSE3 TJFLAG_FORCESSE3 #define TJ_FASTUPSAMPLE TJFLAG_FASTUPSAMPLE #define TJPAD(width) (((width) + 3) & (~3)) DLLEXPORT unsigned long TJBUFSIZE(int width, int height); DLLEXPORT int tjCompress(tjhandle handle, unsigned char *srcBuf, int width, int pitch, int height, int pixelSize, unsigned char *dstBuf, unsigned long *compressedSize, int jpegSubsamp, int jpegQual, int flags); DLLEXPORT int tjDecompress(tjhandle handle, unsigned char *jpegBuf, unsigned long jpegSize, unsigned char *dstBuf, int width, int pitch, int height, int pixelSize, int flags); DLLEXPORT int tjDecompressHeader(tjhandle handle, unsigned char *jpegBuf, unsigned long jpegSize, int *width, int *height); DLLEXPORT int tjDestroy(tjhandle handle); DLLEXPORT char *tjGetErrorStr(void); DLLEXPORT tjhandle tjInitCompress(void); DLLEXPORT tjhandle tjInitDecompress(void); /* TurboJPEG 1.1+ */ #define TJ_YUV 512 DLLEXPORT unsigned long TJBUFSIZEYUV(int width, int height, int jpegSubsamp); DLLEXPORT int tjDecompressHeader2(tjhandle handle, unsigned char *jpegBuf, unsigned long jpegSize, int *width, int *height, int *jpegSubsamp); DLLEXPORT int tjDecompressToYUV(tjhandle handle, unsigned char *jpegBuf, unsigned long jpegSize, unsigned char *dstBuf, int flags); DLLEXPORT int tjEncodeYUV(tjhandle handle, unsigned char *srcBuf, int width, int pitch, int height, int pixelSize, unsigned char *dstBuf, int subsamp, int flags); /* TurboJPEG 1.2+ */ #define TJFLAG_BOTTOMUP 2 #define TJFLAG_FORCEMMX 8 #define TJFLAG_FORCESSE 16 #define TJFLAG_FORCESSE2 32 #define TJFLAG_FORCESSE3 128 #define TJFLAG_FASTUPSAMPLE 256 #define TJFLAG_NOREALLOC 1024 DLLEXPORT unsigned char *tjAlloc(int bytes); DLLEXPORT unsigned long tjBufSize(int width, int height, int jpegSubsamp); DLLEXPORT unsigned long tjBufSizeYUV(int width, int height, int subsamp); DLLEXPORT int tjCompress2(tjhandle handle, const unsigned char *srcBuf, int width, int pitch, int height, int pixelFormat, unsigned char **jpegBuf, unsigned long *jpegSize, int jpegSubsamp, int jpegQual, int flags); DLLEXPORT int tjDecompress2(tjhandle handle, const unsigned char *jpegBuf, unsigned long jpegSize, unsigned char *dstBuf, int width, int pitch, int height, int pixelFormat, int flags); DLLEXPORT int tjEncodeYUV2(tjhandle handle, unsigned char *srcBuf, int width, int pitch, int height, int pixelFormat, unsigned char *dstBuf, int subsamp, int flags); DLLEXPORT void tjFree(unsigned char *buffer); DLLEXPORT tjscalingfactor *tjGetScalingFactors(int *numscalingfactors); DLLEXPORT tjhandle tjInitTransform(void); DLLEXPORT int tjTransform(tjhandle handle, const unsigned char *jpegBuf, unsigned long jpegSize, int n, unsigned char **dstBufs, unsigned long *dstSizes, tjtransform *transforms, int flags); /* TurboJPEG 1.2.1+ */ #define TJFLAG_FASTDCT 2048 #define TJFLAG_ACCURATEDCT 4096 /* TurboJPEG 1.4+ */ DLLEXPORT unsigned long tjBufSizeYUV2(int width, int align, int height, int subsamp); DLLEXPORT int tjCompressFromYUV(tjhandle handle, const unsigned char *srcBuf, int width, int align, int height, int subsamp, unsigned char **jpegBuf, unsigned long *jpegSize, int jpegQual, int flags); DLLEXPORT int tjCompressFromYUVPlanes(tjhandle handle, const unsigned char **srcPlanes, int width, const int *strides, int height, int subsamp, unsigned char **jpegBuf, unsigned long *jpegSize, int jpegQual, int flags); DLLEXPORT int tjDecodeYUV(tjhandle handle, const unsigned char *srcBuf, int align, int subsamp, unsigned char *dstBuf, int width, int pitch, int height, int pixelFormat, int flags); DLLEXPORT int tjDecodeYUVPlanes(tjhandle handle, const unsigned char **srcPlanes, const int *strides, int subsamp, unsigned char *dstBuf, int width, int pitch, int height, int pixelFormat, int flags); DLLEXPORT int tjDecompressHeader3(tjhandle handle, const unsigned char *jpegBuf, unsigned long jpegSize, int *width, int *height, int *jpegSubsamp, int *jpegColorspace); DLLEXPORT int tjDecompressToYUV2(tjhandle handle, const unsigned char *jpegBuf, unsigned long jpegSize, unsigned char *dstBuf, int width, int align, int height, int flags); DLLEXPORT int tjDecompressToYUVPlanes(tjhandle handle, const unsigned char *jpegBuf, unsigned long jpegSize, unsigned char **dstPlanes, int width, int *strides, int height, int flags); DLLEXPORT int tjEncodeYUV3(tjhandle handle, const unsigned char *srcBuf, int width, int pitch, int height, int pixelFormat, unsigned char *dstBuf, int align, int subsamp, int flags); DLLEXPORT int tjEncodeYUVPlanes(tjhandle handle, const unsigned char *srcBuf, int width, int pitch, int height, int pixelFormat, unsigned char **dstPlanes, int *strides, int subsamp, int flags); DLLEXPORT int tjPlaneHeight(int componentID, int height, int subsamp); DLLEXPORT unsigned long tjPlaneSizeYUV(int componentID, int width, int stride, int height, int subsamp); DLLEXPORT int tjPlaneWidth(int componentID, int width, int subsamp); /* TurboJPEG 2.0+ */ #define TJFLAG_STOPONWARNING 8192 #define TJFLAG_PROGRESSIVE 16384 DLLEXPORT int tjGetErrorCode(tjhandle handle); DLLEXPORT char *tjGetErrorStr2(tjhandle handle); DLLEXPORT unsigned char *tjLoadImage(const char *filename, int *width, int align, int *height, int *pixelFormat, int flags); DLLEXPORT int tjSaveImage(const char *filename, unsigned char *buffer, int width, int pitch, int height, int pixelFormat, int flags); /* TurboJPEG 2.1+ */ #define TJFLAG_LIMITSCANS 32768 /** * @} */ #ifdef __cplusplus } #endif #endif ================================================ FILE: luban/src/main/cpp/turbojpeg_wrapper.cpp ================================================ #include #include #include #include "turbojpeg.h" #define LOG_TAG "TurboJpeg" #define LOGI(...) __android_log_print(ANDROID_LOG_INFO, LOG_TAG, __VA_ARGS__) #define LOGE(...) __android_log_print(ANDROID_LOG_ERROR, LOG_TAG, __VA_ARGS__) static const char* get_error_string() { return tjGetErrorStr(); } extern "C" JNIEXPORT jbyteArray JNICALL Java_top_zibin_luban_compression_TurboJpegNative_compress( JNIEnv *env, jobject thiz, jbyteArray rgbData, jint width, jint height, jint quality ) { unsigned long jpegSize = 0; unsigned char* jpegBuf = nullptr; tjhandle handle = nullptr; jbyte* inputData = env->GetByteArrayElements(rgbData, nullptr); if (!inputData) { LOGE("获取输入数据失败 (Failed to get input data)"); return nullptr; } handle = tjInitCompress(); if (!handle) { LOGE("初始化压缩器失败 (Failed to initialize compressor): %s", get_error_string()); env->ReleaseByteArrayElements(rgbData, inputData, JNI_ABORT); return nullptr; } int result = tjCompress2( handle, (unsigned char*)inputData, width, 0, height, TJPF_RGB, &jpegBuf, &jpegSize, TJSAMP_444, quality, TJFLAG_FASTDCT ); env->ReleaseByteArrayElements(rgbData, inputData, JNI_ABORT); if (result != 0) { LOGE("压缩失败 (Compression failed): %s", get_error_string()); tjDestroy(handle); return nullptr; } jbyteArray jpegArray = env->NewByteArray((jsize)jpegSize); if (!jpegArray) { LOGE("创建字节数组失败 (Failed to create byte array)"); tjFree(jpegBuf); tjDestroy(handle); return nullptr; } env->SetByteArrayRegion(jpegArray, 0, (jsize)jpegSize, (jbyte*)jpegBuf); tjFree(jpegBuf); tjDestroy(handle); return jpegArray; } extern "C" JNIEXPORT jstring JNICALL Java_top_zibin_luban_compression_TurboJpegNative_getErrorString( JNIEnv *env, jobject thiz ) { const char* error = get_error_string(); return env->NewStringUTF(error ? error : "未知错误 (Unknown error)"); } ================================================ FILE: luban/src/main/java/top/zibin/luban/algorithm/CompressionCalculator.kt ================================================ package top.zibin.luban.algorithm import kotlin.math.floor import kotlin.math.max import kotlin.math.min import kotlin.math.sqrt data class CompressionTarget( val width: Int, val height: Int, val estimatedSizeKb: Int, val isLongImage: Boolean = false, val targetSizeKb: Int? = null ) class CompressionCalculator { private val baseShort = 1440 private val wallLong = 10800 private val wallRatio = 0.4 private val trapPixels = 40_960_000L private val capPixels = 10_240_000L fun calculateTarget(width: Int, height: Int): CompressionTarget { if (width <= 0 || height <= 0) { return CompressionTarget(0, 0, 0) } val shortSide = min(width, height) val longSide = max(width, height) val ratio = shortSide.toDouble() / longSide val pixelCount = width.toLong() * height var targetShort = baseShort var targetLong = (targetShort / ratio).toInt() if (longSide >= wallLong && ratio > wallRatio) { targetLong = baseShort targetShort = (targetLong * ratio).toInt() } if (pixelCount > trapPixels) { val trapShort = (shortSide * 0.25).toInt() if (trapShort < targetShort) { targetShort = trapShort targetLong = (targetShort / ratio).toInt() } } if (targetShort > shortSide) { targetShort = shortSide targetLong = longSide } val currentPixels = targetShort.toLong() * targetLong if (currentPixels > capPixels) { val scale = floor(sqrt(capPixels.toDouble() / currentPixels) * 1000) / 1000.0 targetShort = (targetShort * scale).toInt() targetLong = (targetLong * scale).toInt() } targetShort = (targetShort / 2) * 2 targetLong = (targetLong / 2) * 2 targetShort = maxOf(2, targetShort) targetLong = maxOf(2, targetLong) val (finalW, finalH) = if (width < height) { Pair(targetShort, targetLong) } else { Pair(targetLong, targetShort) } val finalPixels = finalW.toLong() * finalH val factor = when { finalPixels < 500_000L -> 0.0005 finalPixels < 1_000_000L -> 0.00015 finalPixels < 3_000_000L -> 0.00011 else -> 0.000025 } var estimatedSize = (finalPixels * factor).toInt() estimatedSize = maxOf(20, estimatedSize) if (ratio < 0.2 && estimatedSize < 400) { estimatedSize = maxOf(estimatedSize, 250) } val isLongImage = ratio <= 0.5 val targetSizeKb = if (isLongImage) estimatedSize else null return CompressionTarget( finalW, finalH, estimatedSize, isLongImage, targetSizeKb ) } } ================================================ FILE: luban/src/main/java/top/zibin/luban/api/CompressionTask.kt ================================================ package top.zibin.luban.api /** * 表示一个正在运行的压缩任务。 * * 调用方可以通过该接口取消压缩操作。 * * Represents a running compression task. * * Allows the caller to cancel the compression operation. */ interface CompressionTask { /** * 取消当前压缩任务。 * * Cancels the compression task. */ fun cancel() } ================================================ FILE: luban/src/main/java/top/zibin/luban/api/Luban.kt ================================================ package top.zibin.luban.api import android.content.Context import android.graphics.Bitmap import android.graphics.BitmapFactory import android.net.Uri import kotlinx.coroutines.Dispatchers import kotlinx.coroutines.async import kotlinx.coroutines.awaitAll import kotlinx.coroutines.coroutineScope import kotlinx.coroutines.withContext import top.zibin.luban.algorithm.CompressionCalculator import top.zibin.luban.algorithm.CompressionTarget import top.zibin.luban.compression.Compressor import top.zibin.luban.compression.JpegCompressor import top.zibin.luban.io.ImageData import top.zibin.luban.io.ImageLoader import java.io.File import java.io.FileOutputStream /** * 图片压缩核心类。 * * 使用 Kotlin 协程实现异步压缩,支持单图与多图压缩。 * * Image compression core class. * * Uses Kotlin Coroutines for asynchronous compression, supporting both single and multiple image processing. * * @property compressor 图片压缩实现,默认使用 [JpegCompressor]。 * The image compressor implementation, defaults to [JpegCompressor]. * @property imageLoader 图片加载实现,默认使用 [ImageLoader]。 * The image loader implementation, defaults to [ImageLoader]. * @property calculator 压缩参数计算实现,默认使用 [CompressionCalculator]。 * The compression calculator implementation, defaults to [CompressionCalculator]. */ class Luban @JvmOverloads constructor( private val compressor: Compressor = JpegCompressor(), private val imageLoader: ImageLoader = ImageLoader(), private val calculator: CompressionCalculator = CompressionCalculator() ) { companion object { private val defaultInstance by lazy { Luban() } /** * 为 Java 兼容性或流式 API 使用创建一个 Builder。 * * Creates a builder for Java compatibility or fluent API usage. * * @param context Android 上下文。 * The Android Context. * * @return 一个 [LubanCompat.Builder] 实例。 * A [LubanCompat.Builder] instance. */ @JvmStatic fun with(context: Context): LubanCompat.Builder { return LubanCompat.Builder(context) } /** * 压缩单个 Uri 图片。 * * Compresses a single image from a Uri. * * @param context 用于解析 Uri 的上下文。 * Context required to resolve the Uri. * * @param input 需要压缩的图片 Uri。 * The image Uri to compress. * * @param outputDir 压缩后图片的输出目录,默认为 context.cacheDir。 * The directory where the compressed image will be saved, defaults to context.cacheDir. * * @return 包含压缩后 [File] 或异常信息的 [Result]。 * A [Result] containing the compressed [File] or the exception if failed. */ @JvmOverloads suspend fun compress(context: Context, input: Uri, outputDir: File = context.cacheDir): Result { return defaultInstance.compress(context, input, outputDir) } /** * 压缩单个图片文件。 * * Compresses a single image file。 * * @param input 需要压缩的图片文件。 * The image file to compress。 * * @param outputDir 压缩后图片的输出目录。 * The directory where the compressed image will be saved。 * * @return 包含压缩后 [File] 或异常信息的 [Result]。 * A [Result] containing the compressed [File] or the exception if failed。 */ suspend fun compress(input: File, outputDir: File): Result { return defaultInstance.compress(input, outputDir) } /** * 将单个图片文件压缩到一个指定输出文件。 * * Compresses a single image file to a specific output file. * * @param input 需要压缩的图片文件。 * The image file to compress. * * @param output 指定的输出文件。 * The specific output file destination. * * @return 包含压缩后 [File] 或异常信息的 [Result]。 * A [Result] containing the compressed [File] or the exception if failed. */ suspend fun compressToFile(input: File, output: File): Result { return defaultInstance.compressToFile(input, output) } /** * 并发压缩多个 Uri 图片。 * * Compresses a list of image Uris concurrently. * * @param context 用于解析 Uri 的上下文。 * Context required to resolve the Uris. * * @param inputs 需要压缩的 Uri 列表。 * The list of image Uris to compress. * * @param outputDir 压缩后图片的输出目录,默认为 context.cacheDir。 * The directory where the compressed images will be saved, defaults to context.cacheDir. * * @return [Result] 列表,每个元素包含压缩后 [File] 或异常信息。 * A list of [Result]s, each containing the compressed [File] or exception. */ @JvmOverloads suspend fun compress(context: Context, inputs: List, outputDir: File = context.cacheDir): List> { return defaultInstance.compress(context, inputs, outputDir) } /** * 并发压缩多个图片文件。 * * Compresses a list of image files concurrently. * * @param inputs 需要压缩的图片文件列表。 * The list of image files to compress. * * @param outputDir 压缩后图片的输出目录。 * The directory where the compressed images will be saved. * * @return [Result] 列表,每个元素包含压缩后 [File] 或异常信息。 * A list of [Result]s, each containing the compressed [File] or exception. */ suspend fun compress(inputs: List, outputDir: File): List> { return defaultInstance.compress(inputs, outputDir) } } /** * 压缩单个 Uri 图片。 * * Compresses a single image from a Uri. * * @param context 用于解析 Uri 的上下文。 * Context required to resolve the Uri. * * @param input 需要压缩的图片 Uri。 * The image Uri to compress. * * @param outputDir 压缩后图片的输出目录。 * The directory where the compressed image will be saved. * * @return 包含压缩后 [File] 或异常信息的 [Result]。 * A [Result] containing the compressed [File] or the exception if failed. */ suspend fun compress(context: Context, input: Uri, outputDir: File): Result = runCatching { outputDir.mkdirs() val outputFile = generateOutputFileForUri(input, outputDir) compressInternal(context, input, outputFile) } /** * 压缩单个图片文件。 * * Compresses a single image file. * * @param input 需要压缩的图片文件。 * The image file to compress. * * @param outputDir 压缩后图片的输出目录。 * The directory where the compressed image will be saved. * * @return 包含压缩后 [File] 或异常信息的 [Result]。 * A [Result] containing the compressed [File] or the exception if failed. */ suspend fun compress(input: File, outputDir: File): Result = runCatching { val outputFile = generateOutputFile(input, outputDir) compressInternal(input, outputFile) } /** * 将单个图片文件压缩到一个指定输出文件。 * * Compresses a single image file to a specific output file. * * @param input 需要压缩的图片文件。 * The image file to compress. * * @param output 指定的输出文件。 * The specific output file destination. * * @return 包含压缩后 [File] 或异常信息的 [Result]。 * A [Result] containing the compressed [File] or the exception if failed. */ suspend fun compressToFile(input: File, output: File): Result = runCatching { compressInternal(input, output) } /** * 并发压缩多个 Uri 图片。 * * Compresses a list of image Uris concurrently. * * @param context 用于解析 Uri 的上下文。 * Context required to resolve the Uris. * * @param inputs 需要压缩的 Uri 列表。 * The list of image Uris to compress. * * @param outputDir 压缩后图片的输出目录。 * The directory where the compressed images will be saved. * * @return [Result] 列表,每个元素包含压缩后 [File] 或异常信息。 * A list of [Result]s, each containing the compressed [File] or exception. */ suspend fun compress(context: Context, inputs: List, outputDir: File): List> = coroutineScope { inputs.map { uri -> async { compress(context, uri, outputDir) } }.awaitAll() } /** * 并发压缩多个图片文件。 * * Compresses a list of image files concurrently. * * @param inputs 需要压缩的图片文件列表。 * The list of image files to compress. * * @param outputDir 压缩后图片的输出目录。 * The directory where the compressed images will be saved. * * @return [Result] 列表,每个元素包含压缩后 [File] 或异常信息。 * A list of [Result]s, each containing the compressed [File] or exception. */ suspend fun compress(inputs: List, outputDir: File): List> = coroutineScope { inputs.map { file -> async { compress(file, outputDir) } }.awaitAll() } private suspend fun compressInternal(context: Context, input: Uri, output: File): File = withContext(Dispatchers.IO) { val options = BitmapFactory.Options().apply { inJustDecodeBounds = true } context.contentResolver.openInputStream(input)?.use { BitmapFactory.decodeStream(it, null, options) } val target = calculator.calculateTarget(options.outWidth, options.outHeight) val imageData = imageLoader.loadFromUri(context, input, target.width, target.height) processImage(imageData, output, target, null) } private suspend fun compressInternal(input: File, output: File): File = withContext(Dispatchers.IO) { val options = BitmapFactory.Options().apply { inJustDecodeBounds = true } BitmapFactory.decodeFile(input.absolutePath, options) val target = calculator.calculateTarget(options.outWidth, options.outHeight) val imageData = imageLoader.loadFromFile(input, target.width, target.height) processImage(imageData, output, target, input) } private suspend fun processImage(imageData: ImageData, output: File, target: CompressionTarget, originalFile: File?): File = withContext(Dispatchers.IO) { var bitmap = imageData.bitmap try { if (bitmap.config != Bitmap.Config.RGB_565 && bitmap.config != Bitmap.Config.ARGB_8888) { val rgbBitmap = if (bitmap.config == Bitmap.Config.ARGB_8888) { bitmap.copy(Bitmap.Config.RGB_565, false) } else { bitmap.copy(Bitmap.Config.ARGB_8888, false) } if (rgbBitmap != bitmap) { bitmap.recycle() bitmap = rgbBitmap } } val fixedQuality = if (!target.isLongImage) 60 else null val compressedBytes = compressor.compress(bitmap, target.targetSizeKb, fixedQuality) val originalSizeBytes = (imageData.fileSizeKb * 1024).toLong() val compressedSizeBytes = compressedBytes.size.toLong() output.parentFile?.mkdirs() if (compressedSizeBytes >= originalSizeBytes && originalFile != null && originalFile.exists()) { originalFile.copyTo(output, overwrite = true) } else { FileOutputStream(output).use { fos -> fos.write(compressedBytes) } } output } finally { if (!bitmap.isRecycled) { bitmap.recycle() } } } private fun generateOutputFile(inputFile: File, outputDir: File): File { outputDir.mkdirs() val inputName = inputFile.nameWithoutExtension val timestamp = System.currentTimeMillis() return File(outputDir, "${inputName}_${timestamp}.jpg") } private fun generateOutputFileForUri(uri: Uri, outputDir: File): File { val fileName = uri.lastPathSegment ?: "compressed" val nameWithoutExt = fileName.substringBeforeLast(".") val timestamp = System.currentTimeMillis() return File(outputDir, "${nameWithoutExt}_${timestamp}.jpg") } } suspend fun File.compressTo(outputDir: File): Result { return Luban.compress(this, outputDir) } suspend fun File.compressToFile(output: File): Result { return Luban.compressToFile(this, output) } suspend fun Uri.compressTo(context: Context, outputDir: File = context.cacheDir): Result { return Luban.compress(context, this, outputDir) } suspend fun List.compressTo(outputDir: File): List> { return Luban.compress(this, outputDir) } suspend fun List.compressTo(context: Context, outputDir: File = context.cacheDir): List> { return Luban.compress(context, this, outputDir) } class LubanDsl internal constructor(private val context: Context?) { var outputDir: File? = null private val tasks = mutableListOf Result>() private val batchTasks = mutableListOf List>>() fun compress(input: File): LubanDsl { tasks.add { val currentDir = this@LubanDsl.outputDir if (currentDir != null) { Luban.compress(input, currentDir) } else { Result.failure(IllegalStateException("Output directory is not set")) } } return this } fun compress(input: Uri): LubanDsl { val ctx = context ?: throw IllegalStateException("Context is required for Uri compression") tasks.add { val currentDir = this@LubanDsl.outputDir ?: ctx.cacheDir Luban.compress(ctx, input, currentDir) } return this } @JvmName("compressFiles") fun compress(inputs: List): LubanDsl { batchTasks.add { val currentDir = this@LubanDsl.outputDir if (currentDir != null) { Luban.compress(inputs, currentDir) } else { inputs.map { Result.failure(IllegalStateException("Output directory is not set")) } } } return this } @JvmName("compressUris") fun compress(inputs: List): LubanDsl { val ctx = context ?: throw IllegalStateException("Context is required for Uri compression") batchTasks.add { val currentDir = this@LubanDsl.outputDir ?: ctx.cacheDir Luban.compress(ctx, inputs, currentDir) } return this } suspend fun execute(): List> { val results = mutableListOf>() tasks.forEach { task -> results.add(task()) } batchTasks.forEach { batchTask -> results.addAll(batchTask()) } return results } } suspend fun luban(context: Context, block: LubanDsl.() -> Unit): List> { return LubanDsl(context).apply(block).execute() } suspend fun luban(block: LubanDsl.() -> Unit): List> { return LubanDsl(null).apply(block).execute() } ================================================ FILE: luban/src/main/java/top/zibin/luban/api/LubanCompat.kt ================================================ package top.zibin.luban.api import android.content.Context import android.net.Uri import androidx.lifecycle.Lifecycle import androidx.lifecycle.LifecycleEventObserver import androidx.lifecycle.LifecycleOwner import kotlinx.coroutines.CoroutineScope import kotlinx.coroutines.Dispatchers import kotlinx.coroutines.Job import kotlinx.coroutines.SupervisorJob import kotlinx.coroutines.cancel import kotlinx.coroutines.launch import java.io.File /** * 面向 Java 用户或偏好构建器模式 / 回调式 API 的兼容层。 * * 该类封装了基于协程实现的 [Luban] 压缩 API。 * * Compatibility layer for Java users or those who prefer a Builder pattern / Callback based API. * * This class wraps the coroutine-based [Luban] API. */ class LubanCompat private constructor(builder: Builder) { private val context: Context? = builder.context private val targetDir: File? = builder.targetDir private val compressListener: OnCompressListener? = builder.compressListener private val inputs: List = builder.inputs private val lifecycleOwner: LifecycleOwner? = builder.lifecycleOwner private val job = SupervisorJob() private val scope = CoroutineScope(Dispatchers.Main + job) private fun launch(): CompressionTask { if (inputs.isEmpty() || compressListener == null) { return object : CompressionTask { override fun cancel() {} } } lifecycleOwner?.lifecycle?.addObserver(object : LifecycleEventObserver { override fun onStateChanged(source: LifecycleOwner, event: Lifecycle.Event) { if (event == Lifecycle.Event.ON_DESTROY) { cancel() } } }) compressListener.onStart() scope.launch { for (input in inputs) { if (!isActive) break launch { try { val outputDir = targetDir ?: context?.cacheDir ?: throw IllegalArgumentException("Target directory or Context must be provided") val compressedFileResult = when (input) { is String -> { val file = File(input) if (file.exists()) { Luban.compress(file, outputDir) } else { Result.failure(IllegalArgumentException("File not found: $input")) } } is File -> Luban.compress(input, outputDir) is Uri -> { if (context != null) { Luban.compress(context, input, outputDir) } else { Result.failure(IllegalArgumentException("Context required for Uri compression")) } } else -> Result.failure(IllegalArgumentException("Unsupported input type")) } val result = compressedFileResult.getOrThrow() if (isActive) { compressListener.onSuccess(result) } } catch (e: Throwable) { if (isActive) { compressListener.onError(e) } } } } } return object : CompressionTask { override fun cancel() { this@LubanCompat.cancel() } } } private fun cancel() { job.cancel() } private val isActive: Boolean get() = job.isActive /** * 用于构建压缩请求的 Builder。 * * Builder for constructing a compression request. * * @param context Android 上下文。 * The Android Context. */ class Builder(internal val context: Context?) { internal var targetDir: File? = null internal var compressListener: OnCompressListener? = null internal val inputs: MutableList = mutableListOf() internal var lifecycleOwner: LifecycleOwner? = null /** * 向压缩任务中添加单个文件。 * * Adds a file to the compression list. * * @param file 需要压缩的图片文件。 * The image file to compress. */ fun load(file: File): Builder { inputs.add(file) return this } /** * 向压缩任务中添加文件路径。 * * Adds a file path to the compression list. * * @param path 图片文件的路径。 * The path to the image file. */ fun load(path: String): Builder { inputs.add(path) return this } /** * 向压缩任务中添加图片的 Uri。 * * Adds a Uri to the compression list. * * @param uri 图片的 Uri。 * The image Uri. */ fun load(uri: Uri): Builder { inputs.add(uri) return this } /** * 批量添加待压缩的图片(支持 File、路径字符串或 Uri)。 * * Adds a list of items (File, String path, or Uri) to the compression list. * * @param list 待压缩图片的列表。 * List of images to compress. */ fun load(list: List): Builder { for (item in list) { when (item) { is String -> load(item) is File -> load(item) is Uri -> load(item) } } return this } /** * 设置压缩结果输出目录(通过路径字符串)。 * * Sets the target directory for compressed images. * * @param targetDir 目标目录路径。 * The directory path. */ fun setTargetDir(targetDir: String): Builder { this.targetDir = File(targetDir) return this } /** * 设置压缩结果输出目录(通过目录 File 对象)。 * * Sets the target directory for compressed images. * * @param targetDir 目标目录 File。 * The directory file. */ fun setTargetDir(targetDir: File): Builder { this.targetDir = targetDir return this } /** * 设置压缩过程的回调监听器。 * * Sets the listener for compression events. * * @param listener 压缩回调监听器。 * The callback listener. */ fun setCompressListener(listener: OnCompressListener): Builder { this.compressListener = listener return this } /** * 将压缩任务绑定到指定的 LifecycleOwner,生命周期销毁时会自动取消任务。 * * Binds the compression task to a LifecycleOwner. * The task will be automatically cancelled when the lifecycle is destroyed. * * @param lifecycleOwner 生命周期拥有者(例如 Activity 或 Fragment)。 * The lifecycle owner (e.g., Activity or Fragment). */ fun bindLifecycle(lifecycleOwner: LifecycleOwner): Builder { this.lifecycleOwner = lifecycleOwner return this } /** * 启动压缩任务。 * * Starts the compression task. * * @return 可用于取消操作的 [CompressionTask]。 * A [CompressionTask] that can be used to cancel the operation. */ fun launch(): CompressionTask { return LubanCompat(this).launch() } } companion object { /** * 创建一个新的 Builder 实例。 * * Creates a new Builder instance. * * @param context Android 上下文。 * The Android Context. */ @JvmStatic fun with(context: Context): Builder { return Builder(context) } } } ================================================ FILE: luban/src/main/java/top/zibin/luban/api/OnCompressListener.kt ================================================ package top.zibin.luban.api import java.io.File interface OnCompressListener { fun onStart() fun onSuccess(file: File) fun onError(e: Throwable) } ================================================ FILE: luban/src/main/java/top/zibin/luban/compression/Compressor.kt ================================================ package top.zibin.luban.compression import android.graphics.Bitmap interface Compressor { fun compress(bitmap: Bitmap, targetSizeKb: Int?, fixedQuality: Int? = null): ByteArray } ================================================ FILE: luban/src/main/java/top/zibin/luban/compression/JpegCompressor.kt ================================================ package top.zibin.luban.compression import android.graphics.Bitmap class JpegCompressor : Compressor { override fun compress(bitmap: Bitmap, targetSizeKb: Int?, fixedQuality: Int?): ByteArray { val rgbData = bitmapToRgb(bitmap) if (fixedQuality != null) { return TurboJpegNative.compressOrThrow(rgbData, bitmap.width, bitmap.height, fixedQuality) } if (targetSizeKb == null) { return TurboJpegNative.compressOrThrow(rgbData, bitmap.width, bitmap.height, 60) } val low = 5 val high = 95 var bestData: ByteArray? = null val testResult = TurboJpegNative.compressOrThrow(rgbData, bitmap.width, bitmap.height, 95) val sizeKb = testResult.size / 1024.0 if (sizeKb <= targetSizeKb) { return testResult } var currentLow = low var currentHigh = high while (currentLow <= currentHigh) { val mid = (currentLow + currentHigh) / 2 val compressed = TurboJpegNative.compressOrThrow(rgbData, bitmap.width, bitmap.height, mid) val currentSizeKb = compressed.size / 1024.0 if (currentSizeKb <= targetSizeKb) { bestData = compressed currentLow = mid + 1 } else { currentHigh = mid - 1 } } if (bestData == null) { bestData = TurboJpegNative.compressOrThrow(rgbData, bitmap.width, bitmap.height, 5) } return bestData } private fun bitmapToRgb(bitmap: Bitmap): ByteArray { val width = bitmap.width val height = bitmap.height val pixels = IntArray(width * height) bitmap.getPixels(pixels, 0, width, 0, 0, width, height) val rgbData = ByteArray(width * height * 3) var offset = 0 for (pixel in pixels) { rgbData[offset++] = ((pixel shr 16) and 0xFF).toByte() rgbData[offset++] = ((pixel shr 8) and 0xFF).toByte() rgbData[offset++] = (pixel and 0xFF).toByte() } return rgbData } } ================================================ FILE: luban/src/main/java/top/zibin/luban/compression/TurboJpegNative.kt ================================================ package top.zibin.luban.compression class CompressionException(message: String, cause: Throwable? = null) : RuntimeException(message, cause) object TurboJpegNative { init { System.loadLibrary("turbojpeg-wrapper") } @JvmStatic external fun compress( rgbData: ByteArray, width: Int, height: Int, quality: Int ): ByteArray? @JvmStatic external fun getErrorString(): String fun compressOrThrow( rgbData: ByteArray, width: Int, height: Int, quality: Int ): ByteArray { val result = compress(rgbData, width, height, quality) if (result == null) { val errorMessage = getErrorString().takeIf { it.isNotBlank() } ?: "JPEG compression failed" throw CompressionException( "Failed to compress image (${width}x${height}, quality=$quality): $errorMessage" ) } return result } } ================================================ FILE: luban/src/main/java/top/zibin/luban/io/ImageLoader.kt ================================================ package top.zibin.luban.io import android.content.Context import android.graphics.Bitmap import android.graphics.BitmapFactory import android.net.Uri import androidx.exifinterface.media.ExifInterface import kotlinx.coroutines.Dispatchers import kotlinx.coroutines.withContext import java.io.File import java.io.FileInputStream import java.io.InputStream import androidx.core.graphics.scale data class ImageData( val bitmap: Bitmap, val fileSizeKb: Float ) class ImageLoader { suspend fun loadFromUri( context: Context, uri: Uri, targetWidth: Int = 0, targetHeight: Int = 0 ): ImageData = withContext(Dispatchers.IO) { val fileSizeKb = getFileSizeFromUri(context, uri) val bitmap = context.contentResolver.openInputStream(uri)?.use { inputStream -> decodeStream(inputStream, targetWidth, targetHeight) { context.contentResolver.openInputStream(uri) }?.let { originalBitmap -> val rotation = getRotationFromExifUri(context, uri) if (rotation != 0) { rotateBitmap(originalBitmap, rotation) } else { originalBitmap } } ?: throw IllegalArgumentException("无法解码图片 (Cannot decode image)") } ?: throw IllegalArgumentException("无法打开 URI (Cannot open URI): $uri") ImageData(bitmap, fileSizeKb) } suspend fun loadFromFile(file: File, targetWidth: Int = 0, targetHeight: Int = 0): ImageData = withContext(Dispatchers.IO) { if (!file.exists()) { throw IllegalArgumentException("文件不存在 (File does not exist): ${file.absolutePath}") } val fileSizeKb = file.length() / 1024.0f FileInputStream(file).use { inputStream -> decodeStream(inputStream, targetWidth, targetHeight) { FileInputStream(file) }?.let { originalBitmap -> val rotation = getRotationFromExifFile(file) if (rotation != 0) { rotateBitmap(originalBitmap, rotation) } else { originalBitmap } } ?: throw IllegalArgumentException("无法解码图片 (Cannot decode image)") }.let { bitmap -> ImageData(bitmap, fileSizeKb) } } private fun decodeStream( inputStream: InputStream, targetWidth: Int, targetHeight: Int, openStream: () -> InputStream? ): Bitmap? { val options = BitmapFactory.Options().apply { inJustDecodeBounds = true } BitmapFactory.decodeStream(inputStream, null, options) val originalWidth = options.outWidth val originalHeight = options.outHeight if (originalWidth <= 0 || originalHeight <= 0) { return null } val maxDimension = 8192 val maxMemoryDimension = if (targetWidth > 0 && targetHeight > 0) { maxOf(targetWidth, targetHeight) } else { maxDimension } val finalWidth = if (targetWidth > 0) targetWidth else maxMemoryDimension val finalHeight = if (targetHeight > 0) targetHeight else maxMemoryDimension options.inSampleSize = calculateInSampleSize(options, finalWidth, finalHeight) options.inJustDecodeBounds = false options.inPreferredConfig = Bitmap.Config.RGB_565 options.inScaled = false return openStream()?.use { newStream -> var bitmap = BitmapFactory.decodeStream(newStream, null, options) if (bitmap != null && (bitmap.width > finalWidth || bitmap.height > finalHeight)) { val scaledBitmap = bitmap.scale(finalWidth, finalHeight) if (scaledBitmap != bitmap) { bitmap.recycle() bitmap = scaledBitmap } } bitmap } } private fun calculateInSampleSize( options: BitmapFactory.Options, reqWidth: Int, reqHeight: Int ): Int { val (height: Int, width: Int) = options.run { outHeight to outWidth } var inSampleSize = 1 if (height > reqHeight || width > reqWidth) { val halfHeight: Int = height / 2 val halfWidth: Int = width / 2 while (halfHeight / inSampleSize >= reqHeight && halfWidth / inSampleSize >= reqWidth) { inSampleSize *= 2 } } val pixelCount = (width.toLong() * height) / (inSampleSize * inSampleSize) val maxPixels = 16_000_000L if (pixelCount > maxPixels) { val scale = kotlin.math.sqrt(pixelCount.toDouble() / maxPixels.toDouble()) inSampleSize = (inSampleSize * scale).toInt().coerceAtLeast(1) } return inSampleSize } private fun getFileSizeFromUri(context: Context, uri: Uri): Float { return try { context.contentResolver.openFileDescriptor(uri, "r")?.use { pfd -> pfd.statSize / 1024.0f } ?: 0f } catch (_: Exception) { 0f } } private fun getRotationFromExifFile(file: File): Int { return try { val exif = ExifInterface(file) getRotationFromExif(exif) } catch (_: Exception) { 0 } } private fun getRotationFromExifUri(context: Context, uri: Uri): Int { return try { context.contentResolver.openInputStream(uri)?.use { inputStream -> val exif = ExifInterface(inputStream) getRotationFromExif(exif) } ?: 0 } catch (_: Exception) { 0 } } private fun getRotationFromExif(exif: ExifInterface): Int { return when (exif.getAttributeInt( ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_NORMAL )) { ExifInterface.ORIENTATION_ROTATE_90 -> 90 ExifInterface.ORIENTATION_ROTATE_180 -> 180 ExifInterface.ORIENTATION_ROTATE_270 -> 270 else -> 0 } } private fun rotateBitmap(bitmap: Bitmap, degrees: Int): Bitmap { if (degrees == 0) return bitmap val matrix = android.graphics.Matrix().apply { postRotate(degrees.toFloat()) } val rotatedBitmap = Bitmap.createBitmap( bitmap, 0, 0, bitmap.width, bitmap.height, matrix, true ) if (rotatedBitmap != bitmap) { bitmap.recycle() } return rotatedBitmap } } ================================================ FILE: luban/src/test/java/top/zibin/luban/CompressionCalculatorTest.kt ================================================ package top.zibin.luban import org.junit.Assert.assertEquals import org.junit.Assert.assertTrue import org.junit.Test import top.zibin.luban.algorithm.CompressionCalculator class CompressionCalculatorTest { private val calculator = CompressionCalculator() @Test fun `calculateTarget returns correct dimensions for standard large images`() { val width = 1920 val height = 1080 val target = calculator.calculateTarget(width, height) assertTrue(target.width <= width) assertTrue(target.height <= height) assertEquals(0, target.width % 2) assertEquals(0, target.height % 2) } @Test fun `calculateTarget handles small images correctly`() { val width = 100 val height = 100 val target = calculator.calculateTarget(width, height) assertEquals(width, target.width) assertEquals(height, target.height) } @Test fun `calculateTarget identifies long images`() { val width = 1000 val height = 4000 val target = calculator.calculateTarget(width, height) assertTrue("Should be identified as long image", target.isLongImage) } @Test fun `calculateTarget handles zero or negative dimensions gracefully`() { val target = calculator.calculateTarget(0, 0) assertEquals(0, target.width) assertEquals(0, target.height) val targetNegative = calculator.calculateTarget(-100, 100) assertEquals(0, targetNegative.width) assertEquals(0, targetNegative.height) } @Test fun `calculateTarget respects even dimensions constraint`() { val width = 1333 val height = 750 val target = calculator.calculateTarget(width, height) assertEquals(0, target.width % 2) assertEquals(0, target.height % 2) } } ================================================ FILE: luban/src/test/java/top/zibin/luban/ExampleUnitTest.kt ================================================ package top.zibin.luban import org.junit.Test import org.junit.Assert.* /** * 示例本地单元测试,将在开发机器(宿主环境)上运行。 * * 参见 [测试文档](http://d.android.com/tools/testing)。 * * Example local unit test, which will execute on the development machine (host). * * See [testing documentation](http://d.android.com/tools/testing). */ class ExampleUnitTest { @Test fun addition_isCorrect() { assertEquals(4, 2 + 2) } } ================================================ FILE: settings.gradle.kts ================================================ pluginManagement { repositories { google { content { includeGroupByRegex("com\\.android.*") includeGroupByRegex("com\\.google.*") includeGroupByRegex("androidx.*") } } mavenCentral() gradlePluginPortal() } } dependencyResolutionManagement { repositoriesMode.set(RepositoriesMode.FAIL_ON_PROJECT_REPOS) repositories { google() mavenCentral() } } rootProject.name = "Luban" include(":app") include(":luban") include(":app-java")