Image framework for iOS to display/encode/decode animated WebP, APNG, GIF, and more.
(It's a component of YYKit)

Features

• Display/encode/decode animated image with these types:
      WebP, APNG, GIF.
• Display/encode/decode still image with these types:
      WebP, PNG, GIF, JPEG, JP2, TIFF, BMP, ICO, ICNS.
• Baseline/progressive/interlaced image decode with these types:
      PNG, GIF, JPEG, BMP.
• Display frame based image animation and sprite sheet animation.
• Dynamic memory buffer for lower memory usage.
• Fully compatible with UIImage and UIImageView class.
• Extendable protocol for custom image animation.
• Fully documented.

Usage

Display animated image

// File: [email protected]
UIImage *image = [YYImage imageNamed:@"ani.gif"];
UIImageView *imageView = [[YYAnimatedImageView alloc] initWithImage:image];
[self.view addSubView:imageView];

Display frame animation

// Files: frame1.png, frame2.png, frame3.png
NSArray *paths = @[@"/ani/frame1.png", @"/ani/frame2.png", @"/ani/frame3.png"];
NSArray *times = @[@0.1, @0.2, @0.1];
UIImage *image = [YYFrameImage alloc] initWithImagePaths:paths frameDurations:times repeats:YES];
UIImageView *imageView = [YYAnimatedImageView alloc] initWithImage:image];
[self.view addSubView:imageView];

Display sprite sheet animation

// 8 * 12 sprites in a single sheet image
UIImage *spriteSheet = [UIImage imageNamed:@"sprite-sheet"];
NSMutableArray *contentRects = [NSMutableArray new];
NSMutableArray *durations = [NSMutableArray new];
for (int j = 0; j < 12; j++) {
   for (int i = 0; i < 8; i++) {
       CGRect rect;
       rect.size = CGSizeMake(img.size.width / 8, img.size.height / 12);
       rect.origin.x = img.size.width / 8 * i;
       rect.origin.y = img.size.height / 12 * j;
       [contentRects addObject:[NSValue valueWithCGRect:rect]];
       [durations addObject:@(1 / 60.0)];
   }
}
YYSpriteSheetImage *sprite;
sprite = [[YYSpriteSheetImage alloc] initWithSpriteSheetImage:img
                                                contentRects:contentRects
                                              frameDurations:durations
                                                   loopCount:0];
YYAnimatedImageView *imageView = [YYAnimatedImageView new];
imageView.size = CGSizeMake(img.size.width / 8, img.size.height / 12);
imageView.image = sprite;
[self.view addSubView:imageView];

Animation control

YYAnimatedImageView *imageView = ...;
// pause:
[imageView stopAnimating];
// play:
[imageView startAnimating];
// set frame index:
imageView.currentAnimatedImageIndex = 12;
// get current status
image.currentIsPlayingAnimation;

Image decoder

// Decode single frame:
NSData *data = [NSData dataWithContentsOfFile:@"/tmp/image.webp"];
YYImageDecoder *decoder = [YYImageDecoder decoderWithData:data scale:2.0];
UIImage image = [decoder frameAtIndex:0 decodeForDisplay:YES].image;

// Progressive:
NSMutableData *data = [NSMutableData new];
YYImageDecoder *decoder = [[YYImageDecoder alloc] initWithScale:2.0];
while(newDataArrived) {
   [data appendData:newData];
   [decoder updateData:data final:NO];
   if (decoder.frameCount > 0) {
       UIImage image = [decoder frameAtIndex:0 decodeForDisplay:YES].image;
       // progressive display...
   }
}
[decoder updateData:data final:YES];
UIImage image = [decoder frameAtIndex:0 decodeForDisplay:YES].image;
// final display...

Image encoder

// Encode still image:
YYImageEncoder *jpegEncoder = [[YYImageEncoder alloc] initWithType:YYImageTypeJPEG];
jpegEncoder.quality = 0.9;
[jpegEncoder addImage:image duration:0];
NSData jpegData = [jpegEncoder encode];

// Encode animated image:
YYImageEncoder *webpEncoder = [[YYImageEncoder alloc] initWithType:YYImageTypeWebP];
webpEncoder.loopCount = 5;
[webpEncoder addImage:image0 duration:0.1];
[webpEncoder addImage:image1 duration:0.15];
[webpEncoder addImage:image2 duration:0.2];
NSData webpData = [webpEncoder encode];

Image type detection

// Get image type from image data
YYImageType type = YYImageDetectType(data); 
if (type == YYImageTypePNG) ...

Installation

Manually

1. Download all the files in the YYImage subdirectory.
2. Add the source files to your Xcode project.
3. Link with required frameworks:
   • UIKit
   • CoreFoundation
   • QuartzCore
   • AssetsLibrary
   • ImageIO
   • Accelerate
   • MobileCoreServices
   • libz
4. Import YYImage.h.
5. Notice: if you want to support WebP format, you may add Vendor/WebP.framework(static library) to your Xcode project.

FAQ

Q: Why I can't display WebP image?

A: Make sure you added the WebP.framework in your project. You may call YYImageWebPAvailable() to check whether the WebP subspec is installed correctly.

Q: Why I can't play APNG animation?

A: You should disable the Compress PNG Files and Remove Text Metadata From PNG Files in your project's build settings. Or you can rename your APNG file's extension name with apng.

Documentation

Full API documentation is available on CocoaDocs.
You can also install documentation locally using appledoc.

Requirements

This library requires iOS 6.0+ and Xcode 7.0+.

License

YYImage is provided under the MIT license. See LICENSE file for details.

中文介绍

YYImage: 功能强大的 iOS 图像框架。
(该项目是 YYKit 组件之一)

特性

• 支持以下类型动画图像的播放/编码/解码:
      WebP, APNG, GIF。
• 支持以下类型静态图像的显示/编码/解码:
      WebP, PNG, GIF, JPEG, JP2, TIFF, BMP, ICO, ICNS。
• 支持以下类型图片的渐进式/逐行扫描/隔行扫描解码:
      PNG, GIF, JPEG, BMP。
• 支持多张图片构成的帧动画播放，支持单张图片的 sprite sheet 动画。
• 高效的动态内存缓存管理，以保证高性能低内存的动画播放。
• 完全兼容 UIImage 和 UIImageView，使用方便。
• 保留可扩展的接口，以支持自定义动画。
• 每个类和方法都有完善的文档注释。

用法

显示动画类型的图片

// 文件: [email protected]
UIImage *image = [YYImage imageNamed:@"ani.gif"];
UIImageView *imageView = [[YYAnimatedImageView alloc] initWithImage:image];
[self.view addSubView:imageView];

播放帧动画

// 文件: frame1.png, frame2.png, frame3.png
NSArray *paths = @[@"/ani/frame1.png", @"/ani/frame2.png", @"/ani/frame3.png"];
NSArray *times = @[@0.1, @0.2, @0.1];
UIImage *image = [YYFrameImage alloc] initWithImagePaths:paths frameDurations:times repeats:YES];
UIImageView *imageView = [YYAnimatedImageView alloc] initWithImage:image];
[self.view addSubView:imageView];

播放 sprite sheet 动画

// 8 * 12 sprites in a single sheet image
UIImage *spriteSheet = [UIImage imageNamed:@"sprite-sheet"];
NSMutableArray *contentRects = [NSMutableArray new];
NSMutableArray *durations = [NSMutableArray new];
for (int j = 0; j < 12; j++) {
   for (int i = 0; i < 8; i++) {
       CGRect rect;
       rect.size = CGSizeMake(img.size.width / 8, img.size.height / 12);
       rect.origin.x = img.size.width / 8 * i;
       rect.origin.y = img.size.height / 12 * j;
       [contentRects addObject:[NSValue valueWithCGRect:rect]];
       [durations addObject:@(1 / 60.0)];
   }
}
YYSpriteSheetImage *sprite;
sprite = [[YYSpriteSheetImage alloc] initWithSpriteSheetImage:img
                                                contentRects:contentRects
                                              frameDurations:durations
                                                   loopCount:0];
YYAnimatedImageView *imageView = [YYAnimatedImageView new];
imageView.size = CGSizeMake(img.size.width / 8, img.size.height / 12);
imageView.image = sprite;
[self.view addSubView:imageView];

动画播放控制

YYAnimatedImageView *imageView = ...;
// 暂停:
[imageView stopAnimating];
// 播放:
[imageView startAnimating];
// 设置播放进度:
imageView.currentAnimatedImageIndex = 12;
// 获取播放状态:
image.currentIsPlayingAnimation;
//上面两个属性都支持 KVO。

图片解码

// 解码单帧图片:
NSData *data = [NSData dataWithContentsOfFile:@"/tmp/image.webp"];
YYImageDecoder *decoder = [YYImageDecoder decoderWithData:data scale:2.0];
UIImage image = [decoder frameAtIndex:0 decodeForDisplay:YES].image;

// 渐进式图片解码 (可用于图片下载显示):
NSMutableData *data = [NSMutableData new];
YYImageDecoder *decoder = [[YYImageDecoder alloc] initWithScale:2.0];
while(newDataArrived) {
   [data appendData:newData];
   [decoder updateData:data final:NO];
   if (decoder.frameCount > 0) {
       UIImage image = [decoder frameAtIndex:0 decodeForDisplay:YES].image;
       // progressive display...
   }
}
[decoder updateData:data final:YES];
UIImage image = [decoder frameAtIndex:0 decodeForDisplay:YES].image;
// final display...

图片编码

// 编码静态图 (支持各种常见图片格式):
YYImageEncoder *jpegEncoder = [[YYImageEncoder alloc] initWithType:YYImageTypeJPEG];
jpegEncoder.quality = 0.9;
[jpegEncoder addImage:image duration:0];
NSData jpegData = [jpegEncoder encode];

// 编码动态图 (支持 GIF/APNG/WebP):
YYImageEncoder *webpEncoder = [[YYImageEncoder alloc] initWithType:YYImageTypeWebP];
webpEncoder.loopCount = 5;
[webpEncoder addImage:image0 duration:0.1];
[webpEncoder addImage:image1 duration:0.15];
[webpEncoder addImage:image2 duration:0.2];
NSData webpData = [webpEncoder encode];

图片类型探测

// 获取图片类型
YYImageType type = YYImageDetectType(data); 
if (type == YYImageTypePNG) ...

安装

手动安装

1. 下载 YYImage 文件夹内的所有内容。
2. 将 YYImage 内的源文件添加(拖放)到你的工程。
3. 链接以下 frameworks:
   • UIKit
   • CoreFoundation
   • QuartzCore
   • AssetsLibrary
   • ImageIO
   • Accelerate
   • MobileCoreServices
   • libz
4. 导入 YYImage.h。
5. 注意：如果你需要支持 WebP，可以将 Vendor/WebP.framework(静态库) 加入你的工程。

常见问题

Q: 为什么我不能显示 WebP 图片？

A: 确保 WebP.framework 已经被添加到你的工程内了。你可以调用 YYImageWebPAvailable() 来检查一下 WebP 组件是否被正确安装。

Q: 为什么我不能播放 APNG 动画？

A: 你应该禁用 Build Settings 中的 Compress PNG Files 和 Remove Text Metadata From PNG Files. 或者你也可以把 APNG 文件的扩展名改为apng.

文档

你可以在 CocoaDocs 查看在线 API 文档，也可以用 appledoc 本地生成文档。

系统要求

该项目最低支持 iOS 6.0 和 Xcode 7.0。

许可证

YYImage 使用 MIT 许可证，详情见 LICENSE 文件。

相关链接

移动端图片格式调研

iOS 处理图片的一些小 Tip