从 SDWebImage 5.0 版本开始，我们将 WebP 支持代码和 libwebp 从核心仓库移到了这个独立的仓库。

SDWebImageWebPCoder 支持 WebP 的解码和编码，包括静态 WebP 和动态 WebP。

注意：Apple 的 ImageIO 从 iOS 14/tvOS 14/watchOS 7/macOS 11 开始支持 WebP 解码，因此 SDWebImage 在这些平台上也可以解码 WebP 图像（使用内置的 SDWebImageAWebPCoder 编码器）。但是，它可能存在一些限制，请查看 SDWebImage/SDWebImage#3558。您仍然可以通过添加此编码器来强制在这些平台上使用它。

SDWebImageWebPCoder 可以通过 CocoaPods 获得。要安装它，只需将以下行添加到您的 Podfile 中

pod 'SDWebImageWebPCoder'

github "SDWebImage/SDWebImageWebPCoder"

let package = Package(
    dependencies: [
        .package(url: "https://github.com/SDWebImage/SDWebImageWebPCoder.git", from: "0.3.0")
    ]
)

在使用 SDWebImage 加载 WebP 图像之前，您需要将 WebP Coder 注册到您的 coders 管理器中。建议在您的 App 启动后执行此步骤（例如在 AppDelegate 方法中）。

// Add coder
SDImageWebPCoder *webPCoder = [SDImageWebPCoder sharedCoder];
[[SDImageCodersManager sharedManager] addCoder:webPCoder];

// Add coder
let WebPCoder = SDImageWebPCoder.shared
SDImageCodersManager.shared.addCoder(WebPCoder)

某些图像服务器提供商可能会尝试检测客户端支持的格式。默认情况下，SDWebImage 使用 image/*,*/*;q=0.8 作为 Accept。您也可以使用 image/webp 来修改它。

[[SDWebImageDownloader sharedDownloader] setValue:@"image/webp,image/*,*/*;q=0.8" forHTTPHeaderField:@"Accept"];

SDWebImageDownloader.shared.setValue("image/webp,image/*,*/*;q=0.8", forHTTPHeaderField:"Accept")

// WebP online image loading
NSURL *webpURL;
UIImageView *imageView;
[imageView sd_setImageWithURL:webpURL];

// WebP online image loading
let webpURL: URL
let imageView: UIImageView
imageView.sd_setImage(with: webpURL)

// WebP progressive loading for animated image
NSURL *webpURL;
SDAnimatedImageView *imageView;
imageView.shouldIncrementalLoad = YES;
[imageView sd_setImageWithURL:webpURL placeholderImage:nil options:SDWebImageProgressiveLoad];

// WebP progressive loading for animated image
let webpURL: URL
let imageView: SDAnimatedImageView
imageView.shouldIncrementalLoad = true
imageView.sd_setImage(with: webpURL, placeholderImage: nil, options: [.progressiveLoad])

// WebP image decoding
NSData *webpData;
UIImage *image = [[SDImageWebPCoder sharedCoder] decodedImageWithData:webpData options:nil];

// WebP image decoding
let webpData: Data
let image = SDImageWebPCoder.shared.decodedImage(with: data, options: nil)

// WebP thumbnail image decoding
NSData *webpData;
CGSize thumbnailSize = CGSizeMake(300, 300);
UIImage *thumbnailImage = [[SDImageWebPCoder sharedCoder] decodedImageWithData:webpData options:@{SDImageCoderDecodeThumbnailPixelSize : @(thumbnailSize)}];

// WebP thumbnail image decoding
let webpData: Data
let thumbnailSize = CGSize(width: 300, height: 300)
let image = SDImageWebPCoder.shared.decodedImage(with: data, options: [.decodeThumbnailPixelSize: thumbnailSize])

// WebP thumbnail image decoding
NSData *webpData;
NSUInteger limitBytes = 1024 * 1024; // 1MB
UIImage *image = [[SDImageWebPCoder sharedCoder] decodedImageWithData:webpData options:@{SDImageCoderDecodeScaleDownLimitBytes : @(limitBytes)}];
// The image pixel buffer is guaranteed to less than 1MB in RAM (may scale down or full size), suitable for large image

// WebP thumbnail image decoding
let webpData: Data
let limitBytes = 1024 * 1024 // 1MB
let image = SDImageWebPCoder.shared.decodedImage(with: data, options: [.decodeScaleDownLimitBytes: limitBytes])
// The image pixel buffer is guaranteed to less than 1MB in RAM (may scale down or full size), suitable for large image

// WebP image encoding
UIImage *image;
NSData *webpData = [[SDImageWebPCoder sharedCoder] encodedDataWithImage:image format:SDImageFormatWebP options:nil];
// Animated encoding
NSArray<SDImageFrames *> *frames;
NSData *awebpData = [[SDImageWebPCoder sharedCoder] encodedDataWithFrames:frames loopCount:0 format:SDImageFormatWebP options:nil];
// Encode Quality
NSData *lossyWebpData = [[SDImageWebPCoder sharedCoder] encodedDataWithImage:image format:SDImageFormatWebP options:@{SDImageCoderEncodeCompressionQuality : @(0.1)}]; // [0, 1] compression quality
NSData *limitedWebpData = [[SDImageWebPCoder sharedCoder] encodedDataWithImage:image format:SDImageFormatWebP options:@{SDImageCoderEncodeMaxFileSize : @(1024 * 10)}]; // v0.6.0 feature, limit output file size <= 10KB

// WebP image encoding
let image: UIImage
let webpData = SDImageWebPCoder.shared.encodedData(with: image, format: .webP, options: nil)
// Animated encoding
let frames: [SDImageFrame]
let awebpData = SDImageWebPCoder.shared.encodedData(with: frames, loopCount: 0, format: .webP, options: nil)
// Encode Quality
let lossyWebpData = SDImageWebPCoder.shared.encodedData(with: image, format: .webP, options: [.encodeCompressionQuality: 0.1]) // [0, 1] compression quality
let limitedWebpData = SDImageWebPCoder.shared.encodedData(with: image, format: .webP, options: [.encodeMaxFileSize: 1024 * 10]) // v0.6.0 feature, limit output file size <= 10KB

// WebP image thumbnail encoding
UIImage *image;
NSData *thumbnailWebpData = [[SDImageWebPCoder sharedCoder] encodedDataWithImage:image format:SDImageFormatWebP options:@{SDImageCoderEncodeMaxPixelSize : @(CGSizeMake(200, 200))}]; // v0.6.1 feature, encoding max pixel size

// WebP image thumbnail encoding
let image: UIImage
let thumbnailWebpData = SDImageWebPCoder.shared.encodedData(with: image, format: .webP, options: [.encodeMaxPixelSize: CGSize(width: 200, height: 200)]) // v0.6.1 feature, encoding max pixel size

// Animated encoding
NSMutableArray<SDImageFrames *> *frames = [NSMutableArray array];
for (size_t i = 0; i < images.count; i++) {
    SDImageFrame *frame = [SDImageFrame frameWithImage:images[i] duration:0.1];
    [frames appendObject:frame];
}
NSData *awebpData = [[SDImageWebPCoder sharedCoder] encodedDataWithFrames:frames loopCount:0 format:SDImageFormatWebP options:nil];

// Animated encoding
var frames: [SDImageFrame] = []
for i in 0..<images.count {
    let frame = SDImageFrame(image: images[i], duration: 0.1)
    frames.append(frame)
}
let awebpData = SDImageWebPCoder.shared.encodedData(with: frames, loopCount: 0, format: .webP, options: nil)

我们使用的 WebP 编解码器 libwebp 支持一些高级控制选项，用于编码/解码。您可以使用包装器顶层 API 将它们传递给 libwebp

UIImage *image;
SDImageCoderOptions *options = @{SDImageCoderEncodeWebPMethod: @(0), SDImageCoderEncodeWebPAlphaCompression: @(100)};
NSData *data = [SDImageWebPCoder.sharedCoder encodedDataWithImage:image format:SDImageFormatWebP options:options];
// Will translate into:
// config->method = 0;
// config->alpha_quality = 100;

let image: UIImage
let options = [.encodeWebPMethod: 0, .encodeWebPAlphaCompression: 100]
let data = SDImageWebPCoder.shared.encodedData(with: image, format: .webP, options: options)
// Will translate into:
// config->method = 0;
// config->alpha_quality = 100;

要运行示例项目，请克隆 repo，并首先从根目录运行 pod install。然后打开 SDWebImageWebPCoder.xcworkspace。

这是一个演示如何通过 SDWebImageWebPCoderExample target 使用 WebP 和动态 WebP 图像的示例。

SDWebImageWebPCoder 在 MIT 许可证下可用。有关更多信息，请参阅 LICENSE 文件。

SDWebImageWebPCoder

要求

安装

CocoaPods

Carthage

Swift Package Manager (Xcode 11+)

使用方法

添加 Coder

修改 HTTP Accept Header

加载

渐进式动画加载 (0.5.0+)

解码

缩略图解码 (0.4.0+)

使用限制字节解码 (0.12.0+)

编码

缩略图编码 (0.6.1+)

动态 WebP 编码 (0.10+)

高级 WebP 编解码器选项 (0.8+)

示例

截图

作者

许可证