Fix the issue that animated image (which use a canvas) should also sc…

…ale the canvas size

SDWebImageWebPCoder/Classes/SDImageWebPCoder.m

@@ -24,6 +24,38 @@
 
 #import <Accelerate/Accelerate.h>
 
+/// Calculate the actual thumnail pixel size
+static CGSize SDCalculateThumbnailSize(CGSize fullSize, BOOL preserveAspectRatio, CGSize thumbnailSize) {
+ CGFloat width = fullSize.width;
+ CGFloat height = fullSize.height;
+ CGFloat resultWidth;
+ CGFloat resultHeight;
+
+ if (width == 0 || height == 0 || thumbnailSize.width == 0 || thumbnailSize.height == 0 || (width <= thumbnailSize.width && height <= thumbnailSize.height)) {
+ // Full Pixel
+ resultWidth = width;
+ resultHeight = height;
+ } else {
+ // Thumbnail
+ if (preserveAspectRatio) {
+ CGFloat pixelRatio = width / height;
+ CGFloat thumbnailRatio = thumbnailSize.width / thumbnailSize.height;
+ if (pixelRatio > thumbnailRatio) {
+ resultWidth = thumbnailSize.width;
+ resultHeight = ceil(thumbnailSize.width / pixelRatio);
+ } else {
+ resultHeight = thumbnailSize.height;
+ resultWidth = ceil(thumbnailSize.height * pixelRatio);
+ }
+ } else {
+ resultWidth = thumbnailSize.width;
+ resultHeight = thumbnailSize.height;
+ }
+ }
+
+ return CGSizeMake(resultWidth, resultHeight);
+}
+
 #ifndef SD_LOCK
 #define SD_LOCK(lock) dispatch_semaphore_wait(lock, DISPATCH_TIME_FOREVER);
 #endif
@@ -64,8 +96,6 @@ @implementation SDImageWebPCoder {
  BOOL _hasAnimation;
  BOOL _hasAlpha;
  BOOL _finished;
- CGFloat _canvasWidth;
- CGFloat _canvasHeight;
  dispatch_semaphore_t _lock;
  NSUInteger _currentBlendIndex;
  BOOL _preserveAspectRatio;
@@ -159,7 +189,7 @@ - (UIImage *)decodedImageWithData:(NSData *)data options:(nullable SDImageCoderO
  WebPDemuxDelete(demuxer);
  return nil;
  }
- CGColorSpaceRef colorSpace = [self sd_colorSpaceWithDemuxer:demuxer];
+ CGColorSpaceRef colorSpace = [self sd_createColorSpaceWithDemuxer:demuxer];
 
  if (!hasAnimation || decodeFirstFrame) {
  // first frame for animated webp image
@@ -177,19 +207,14 @@ - (UIImage *)decodedImageWithData:(NSData *)data options:(nullable SDImageCoderO
  return firstFrameImage;
  }
 
- int loopCount = WebPDemuxGetI(demuxer, WEBP_FF_LOOP_COUNT);
- int canvasWidth = WebPDemuxGetI(demuxer, WEBP_FF_CANVAS_WIDTH);
- int canvasHeight = WebPDemuxGetI(demuxer, WEBP_FF_CANVAS_HEIGHT);
- BOOL hasAlpha = flags & ALPHA_FLAG;
- CGBitmapInfo bitmapInfo = kCGBitmapByteOrder32Host;
- bitmapInfo |= hasAlpha ? kCGImageAlphaPremultipliedFirst : kCGImageAlphaNoneSkipFirst;
- CGContextRef canvas = CGBitmapContextCreate(NULL, canvasWidth, canvasHeight, 8, 0, [SDImageCoderHelper colorSpaceGetDeviceRGB], bitmapInfo);
+ CGContextRef canvas = [self sd_createCanvasWithDemuxer:demuxer colorSpace:colorSpace preserveAspectRatio:preserveAspectRatio thumbnailSize:thumbnailSize];
  if (!canvas) {
  WebPDemuxDelete(demuxer);
  CGColorSpaceRelease(colorSpace);
  return nil;
  }
 
+ int loopCount = WebPDemuxGetI(demuxer, WEBP_FF_LOOP_COUNT);
  NSMutableArray<SDImageFrame *> *frames = [NSMutableArray array];
 
  do {
@@ -305,7 +330,7 @@ - (UIImage *)incrementalDecodedImageWithOptions:(SDImageCoderOptions *)options {
  return nil;
  }
 
- CGContextRef canvas = CGBitmapContextCreate(NULL, width, height, 8, 0, [SDImageCoderHelper colorSpaceGetDeviceRGB], bitmapInfo);
+ CGContextRef canvas = [self sd_createCanvasWithDemuxer:_demux colorSpace:colorSpaceRef preserveAspectRatio:_preserveAspectRatio thumbnailSize:_thumbnailSize];
  if (!canvas) {
  CGImageRelease(imageRef);
  return nil;
@@ -413,25 +438,12 @@ - (nullable CGImageRef)sd_createWebpImageWithData:(WebPData)webpData colorSpace:
 
  int width = config.input.width;
  int height = config.input.height;
- if (width == 0 || height == 0 || thumbnailSize.width == 0 || thumbnailSize.height == 0 || (width <= thumbnailSize.width && height <= thumbnailSize.height)) {
- // Full Pixel
- } else {
- // Thumbnail
+ CGSize resultSize = SDCalculateThumbnailSize(CGSizeMake(width, height), preserveAspectRatio, thumbnailSize);
+ if (resultSize.width != width || resultSize.height != height) {
+ // Use scaling
  config.options.use_scaling = 1;
- if (preserveAspectRatio) {
- CGFloat pixelRatio = (CGFloat)width / (CGFloat)height;
- CGFloat thumbnailRatio = thumbnailSize.width / thumbnailSize.height;
- if (pixelRatio > thumbnailRatio) {
- config.options.scaled_width = thumbnailSize.width;
- config.options.scaled_height = thumbnailSize.width / pixelRatio;
- } else {
- config.options.scaled_height = thumbnailSize.height;
- config.options.scaled_width = thumbnailSize.height * pixelRatio;
- }
- } else {
- config.options.scaled_width = thumbnailSize.width;
- config.options.scaled_height = thumbnailSize.height;
- }
+ config.options.scaled_width = resultSize.width;
+ config.options.scaled_height = resultSize.height;
  }
 
  // Decode the WebP image data into a RGBA value array
@@ -451,7 +463,7 @@ - (nullable CGImageRef)sd_createWebpImageWithData:(WebPData)webpData colorSpace:
  size_t bitsPerPixel = 32;
  size_t bytesPerRow = config.output.u.RGBA.stride;
  CGColorRenderingIntent renderingIntent = kCGRenderingIntentDefault;
- CGImageRef imageRef = CGImageCreate(width, height, bitsPerComponent, bitsPerPixel, bytesPerRow, colorSpaceRef, bitmapInfo, provider, NULL, NO, renderingIntent);
+ CGImageRef imageRef = CGImageCreate(resultSize.width, resultSize.height, bitsPerComponent, bitsPerPixel, bytesPerRow, colorSpaceRef, bitmapInfo, provider, NULL, NO, renderingIntent);
 
  CGDataProviderRelease(provider);
 
@@ -469,7 +481,7 @@ - (NSTimeInterval)sd_frameDurationWithIterator:(WebPIterator)iter {
 }
 
 // Create and return the correct colorspace by checking the ICC Profile
-- (nonnull CGColorSpaceRef)sd_colorSpaceWithDemuxer:(nonnull WebPDemuxer *)demuxer CF_RETURNS_RETAINED {
+- (nonnull CGColorSpaceRef)sd_createColorSpaceWithDemuxer:(nonnull WebPDemuxer *)demuxer CF_RETURNS_RETAINED {
  // WebP contains ICC Profile should use the desired colorspace, instead of default device colorspace
  // See: https://developers.google.com/speed/webp/docs/riff_container#color_profile
 
@@ -508,6 +520,20 @@ - (nonnull CGColorSpaceRef)sd_colorSpaceWithDemuxer:(nonnull WebPDemuxer *)demux
  return colorSpaceRef;
 }
 
+- (CGContextRef)sd_createCanvasWithDemuxer:(nonnull WebPDemuxer *)demuxer colorSpace:(nonnull CGColorSpaceRef)colorSpace preserveAspectRatio:(BOOL)preserveAspectRatio thumbnailSize:(CGSize)thumbnailSize CF_RETURNS_RETAINED {
+ uint32_t flags = WebPDemuxGetI(demuxer, WEBP_FF_FORMAT_FLAGS);
+ int canvasWidth = WebPDemuxGetI(demuxer, WEBP_FF_CANVAS_WIDTH);
+ int canvasHeight = WebPDemuxGetI(demuxer, WEBP_FF_CANVAS_HEIGHT);
+ BOOL hasAlpha = flags & ALPHA_FLAG;
+ CGBitmapInfo bitmapInfo = kCGBitmapByteOrder32Host;
+ bitmapInfo |= hasAlpha ? kCGImageAlphaPremultipliedFirst : kCGImageAlphaNoneSkipFirst;
+
+ CGSize canvasSize = SDCalculateThumbnailSize(CGSizeMake(canvasWidth, canvasHeight), preserveAspectRatio, thumbnailSize);
+ CGContextRef canvas = CGBitmapContextCreate(NULL, canvasSize.width, canvasSize.height, 8, 0, colorSpace, bitmapInfo);
+
+ return canvas;
+}
+
 #pragma mark - Encode
 - (BOOL)canEncodeToFormat:(SDImageFormat)format {
  return (format == SDImageFormatWebP);
@@ -784,8 +810,6 @@ - (BOOL)scanAndCheckFramesValidWithDemuxer:(WebPDemuxer *)demuxer {
 
  _hasAnimation = hasAnimation;
  _hasAlpha = hasAlpha;
- _canvasWidth = canvasWidth;
- _canvasHeight = canvasHeight;
  _frameCount = frameCount;
  _loopCount = loopCount;
 
@@ -875,7 +899,7 @@ - (UIImage *)animatedImageFrameAtIndex:(NSUInteger)index {
 - (UIImage *)safeStaticImageFrame {
  UIImage *image;
  if (!_colorSpace) {
- _colorSpace = [self sd_colorSpaceWithDemuxer:_demux];
+ _colorSpace = [self sd_createColorSpaceWithDemuxer:_demux];
  }
  // Static WebP image
  WebPIterator iter;
@@ -898,18 +922,16 @@ - (UIImage *)safeStaticImageFrame {
 }
 
 - (UIImage *)safeAnimatedImageFrameAtIndex:(NSUInteger)index {
+ if (!_colorSpace) {
+ _colorSpace = [self sd_createColorSpaceWithDemuxer:_demux];
+ }
  if (!_canvas) {
- CGBitmapInfo bitmapInfo = kCGBitmapByteOrder32Host;
- bitmapInfo |= _hasAlpha ? kCGImageAlphaPremultipliedFirst : kCGImageAlphaNoneSkipFirst;
- CGContextRef canvas = CGBitmapContextCreate(NULL, _canvasWidth, _canvasHeight, 8, 0, [SDImageCoderHelper colorSpaceGetDeviceRGB], bitmapInfo);
+ CGContextRef canvas = [self sd_createCanvasWithDemuxer:_demux colorSpace:_colorSpace preserveAspectRatio:_preserveAspectRatio thumbnailSize:_thumbnailSize];
  if (!canvas) {
  return nil;
  }
  _canvas = canvas;
  }
- if (!_colorSpace) {
- _colorSpace = [self sd_colorSpaceWithDemuxer:_demux];
- }
 
  SDWebPCoderFrame *frame = _frames[index];
  UIImage *image;
@@ -929,7 +951,7 @@ - (UIImage *)safeAnimatedImageFrameAtIndex:(NSUInteger)index {
  } else {
  // Else, this can happen when one image set to different imageViews or one loop end. So we should clear the canvas. Then draw until the canvas is ready.
  if (_currentBlendIndex != NSNotFound) {
- CGContextClearRect(_canvas, CGRectMake(0, 0, _canvasWidth, _canvasHeight));
+ CGContextClearRect(_canvas, CGRectMake(0, 0, CGBitmapContextGetWidth(_canvas), CGBitmapContextGetHeight(_canvas)));
  }
 
  // Then, loop from the blend from index, draw each of previous frames on the canvas.