SDWebImageWebPCoder

Starting with the SDWebImage 5.0 version, we moved the WebP support code and libwebp from the Core Repo to this stand-alone repo.

SDWebImageWebPCoder supports both WebP decoding and encoding, for Static WebP or Animated WebP as well.

Note: Apple's ImageIO supports WebP decoding from iOS 14/tvOS 14/watchOS 7/macOS 11, so SDWebImage on those platform can also decode WebP images (using SDWebImageAWebPCoder built-in coder). However it may contains some limitation, check SDWebImage/SDWebImage#3558, you can still force to use this coder on those platforms by adding this coder.

Requirements

iOS 9.0
macOS 10.11
tvOS 9.0
watchOS 2.0
Xcode 11.0

Installation

CocoaPods

SDWebImageWebPCoder is available through CocoaPods. To install it, simply add the following line to your Podfile:

pod 'SDWebImageWebPCoder'

Carthage

SDWebImageWebPCoder is available through Carthage.

github "SDWebImage/SDWebImageWebPCoder"

Swift Package Manager (Xcode 11+)

SDWebImageWebPCoder is available through Swift Package Manager.

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

Usage

Add Coder

Before using SDWebImage to load WebP images, you need to register the WebP Coder to your coders manager. This step is recommended to be done after your App launch (like AppDelegate method).

Objective-C

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

Swift

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

Modify HTTP Accept Header

Some of image server provider may try to detect the client supported format, by default, SDWebImage use image/*,*/*;q=0.8 for Accept. You can modify it with the image/webp as well.

Objective-C

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

Swift

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

Loading

Objective-C

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

Swift

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

Progressive Animation Loading (0.5.0+)

Objective-C

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

Swift

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

Decoding

Objective-C

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

Swift

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

Thumbnail Decoding (0.4.0+)

Objective-C

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

Swift

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

Decoding with limit bytes (0.12.0+)

Objective-C

// 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

Swift

// 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

Encoding

Objective-c

// 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

Swift

// 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

Thumbnail Encoding (0.6.1+)

Objective-C

// 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

Swift

// 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

See more documentation in SDWebImage Wiki - Coders

Animated WebP Encoding (0.10+)

Objective-c

// 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];

Swift

// 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)

Advanced WebP codec options (0.8+)

The WebP codec libwebp we use, supports some advanced control options for encoding/decoding. You can pass them to libwebp by using the wrapper top level API:

Objective-C

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;

Swift

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;

Example

To run the example project, clone the repo, and run pod install from the root directory first. Then open SDWebImageWebPCoder.xcworkspace.

This is a demo to show how to use WebP and animated WebP images via SDWebImageWebPCoderExample target.

Screenshot

These WebP images are from WebP Gallery and GIF vs APNG vs WebP

Author

Bogdan Poplauschi DreamPiggy

License

SDWebImageWebPCoder is available under the MIT license. See the LICENSE file for more info.