Merge pull request #3047 from dreampiggy/behavior_sdanimatedimage_encoding_animation

Add the support for that UIImage+MultiFormat methods on SDAnimartedImage, which supports encoding the animation like GIF/APNG/WebP with lower compression quality.

SDWebImage/Core/SDAnimatedImage.m

@@ -13,6 +13,8 @@
 #import "SDImageFrame.h"
 #import "UIImage+MemoryCacheCost.h"
 #import "UIImage+Metadata.h"
+#import "UIImage+MultiFormat.h"
+#import "SDImageCoderHelper.h"
 #import "SDImageAssetManager.h"
 #import "objc/runtime.h"
 
@@ -327,3 +329,62 @@ static CGFloat SDImageScaleFromPath(NSString *string) {
 }
 
 @end
+
+@implementation SDAnimatedImage (MultiFormat)
+
++ (nullable UIImage *)sd_imageWithData:(nullable NSData *)data {
+    return [self sd_imageWithData:data scale:1];
+}
+
++ (nullable UIImage *)sd_imageWithData:(nullable NSData *)data scale:(CGFloat)scale {
+    return [self sd_imageWithData:data scale:scale firstFrameOnly:NO];
+}
+
++ (nullable UIImage *)sd_imageWithData:(nullable NSData *)data scale:(CGFloat)scale firstFrameOnly:(BOOL)firstFrameOnly {
+    if (!data) {
+        return nil;
+    }
+    return [[self alloc] initWithData:data scale:scale options:@{SDImageCoderDecodeFirstFrameOnly : @(firstFrameOnly)}];
+}
+
+- (nullable NSData *)sd_imageData {
+    NSData *imageData = self.animatedImageData;
+    if (imageData) {
+        return imageData;
+    } else {
+        return [self sd_imageDataAsFormat:self.animatedImageFormat];
+    }
+}
+
+- (nullable NSData *)sd_imageDataAsFormat:(SDImageFormat)imageFormat {
+    return [self sd_imageDataAsFormat:imageFormat compressionQuality:1];
+}
+
+- (nullable NSData *)sd_imageDataAsFormat:(SDImageFormat)imageFormat compressionQuality:(double)compressionQuality {
+    return [self sd_imageDataAsFormat:imageFormat compressionQuality:compressionQuality firstFrameOnly:NO];
+}
+
+- (nullable NSData *)sd_imageDataAsFormat:(SDImageFormat)imageFormat compressionQuality:(double)compressionQuality firstFrameOnly:(BOOL)firstFrameOnly {
+    if (firstFrameOnly) {
+        // First frame, use super implementation
+        return [super sd_imageDataAsFormat:imageFormat compressionQuality:compressionQuality firstFrameOnly:firstFrameOnly];
+    }
+    NSUInteger frameCount = self.animatedImageFrameCount;
+    if (frameCount <= 1) {
+        // Static image, use super implementation
+        return [super sd_imageDataAsFormat:imageFormat compressionQuality:compressionQuality firstFrameOnly:firstFrameOnly];
+    }
+    // Keep animated image encoding, loop each frame.
+    NSMutableArray<SDImageFrame *> *frames = [NSMutableArray arrayWithCapacity:frameCount];
+    for (size_t i = 0; i < frameCount; i++) {
+        UIImage *image = [self animatedImageFrameAtIndex:i];
+        NSTimeInterval duration = [self animatedImageDurationAtIndex:i];
+        SDImageFrame *frame = [SDImageFrame frameWithImage:image duration:duration];
+        [frames addObject:frame];
+    }
+    UIImage *animatedImage = [SDImageCoderHelper animatedImageWithFrames:frames];
+    NSData *imageData = [animatedImage sd_imageDataAsFormat:imageFormat compressionQuality:compressionQuality firstFrameOnly:firstFrameOnly];
+    return imageData;
+}
+
+@end

SDWebImage/Core/UIImage+MultiFormat.h

@@ -45,6 +45,7 @@
 /**
  Encode the current image to the data, the image format is unspecified
 
+ @note If the receiver is `SDAnimatedImage`, this will return the animated image data if available. No more extra encoding process.
  @return The encoded data. If can't encode, return nil
  */
 - (nullable NSData *)sd_imageData;