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Add @autoreleasepool around a region of code that makes many allocati…
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…ons in a loop.
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Tim Johnsen committed Jan 12, 2016
1 parent 7cee50c commit 4951be2
Showing 1 changed file with 60 additions and 58 deletions.
118 changes: 60 additions & 58 deletions FLAnimatedImage/FLAnimatedImage.m
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Expand Up @@ -228,70 +228,72 @@ - (instancetype)initWithAnimatedGIFData:(NSData *)data
NSUInteger skippedFrameCount = 0;
NSMutableDictionary *delayTimesForIndexesMutable = [NSMutableDictionary dictionaryWithCapacity:imageCount];
for (size_t i = 0; i < imageCount; i++) {
CGImageRef frameImageRef = CGImageSourceCreateImageAtIndex(_imageSource, i, NULL);
if (frameImageRef) {
UIImage *frameImage = [UIImage imageWithCGImage:frameImageRef];
// Check for valid `frameImage` before parsing its properties as frames can be corrupted (and `frameImage` even `nil` when `frameImageRef` was valid).
if (frameImage) {
// Set poster image
if (!self.posterImage) {
_posterImage = frameImage;
// Set its size to proxy our size.
_size = _posterImage.size;
// Remember index of poster image so we never purge it; also add it to the cache.
_posterImageFrameIndex = i;
[self.cachedFramesForIndexes setObject:self.posterImage forKey:@(self.posterImageFrameIndex)];
[self.cachedFrameIndexes addIndex:self.posterImageFrameIndex];
}

// Get `DelayTime`
// Note: It's not in (1/100) of a second like still falsely described in the documentation as per iOS 8 (rdar://19507384) but in seconds stored as `kCFNumberFloat32Type`.
// Frame properties example:
// {
// ColorModel = RGB;
// Depth = 8;
// PixelHeight = 960;
// PixelWidth = 640;
// "{GIF}" = {
// DelayTime = "0.4";
// UnclampedDelayTime = "0.4";
// };
// }

NSDictionary *frameProperties = (__bridge_transfer NSDictionary *)CGImageSourceCopyPropertiesAtIndex(_imageSource, i, NULL);
NSDictionary *framePropertiesGIF = [frameProperties objectForKey:(id)kCGImagePropertyGIFDictionary];

// Try to use the unclamped delay time; fall back to the normal delay time.
NSNumber *delayTime = [framePropertiesGIF objectForKey:(id)kCGImagePropertyGIFUnclampedDelayTime];
if (!delayTime) {
delayTime = [framePropertiesGIF objectForKey:(id)kCGImagePropertyGIFDelayTime];
}
// If we don't get a delay time from the properties, fall back to `kDelayTimeIntervalDefault` or carry over the preceding frame's value.
const NSTimeInterval kDelayTimeIntervalDefault = 0.1;
if (!delayTime) {
if (i == 0) {
FLLog(FLLogLevelInfo, @"Falling back to default delay time for first frame %@ because none found in GIF properties %@", frameImage, frameProperties);
@autoreleasepool {
CGImageRef frameImageRef = CGImageSourceCreateImageAtIndex(_imageSource, i, NULL);
if (frameImageRef) {
UIImage *frameImage = [UIImage imageWithCGImage:frameImageRef];
// Check for valid `frameImage` before parsing its properties as frames can be corrupted (and `frameImage` even `nil` when `frameImageRef` was valid).
if (frameImage) {
// Set poster image
if (!self.posterImage) {
_posterImage = frameImage;
// Set its size to proxy our size.
_size = _posterImage.size;
// Remember index of poster image so we never purge it; also add it to the cache.
_posterImageFrameIndex = i;
[self.cachedFramesForIndexes setObject:self.posterImage forKey:@(self.posterImageFrameIndex)];
[self.cachedFrameIndexes addIndex:self.posterImageFrameIndex];
}

// Get `DelayTime`
// Note: It's not in (1/100) of a second like still falsely described in the documentation as per iOS 8 (rdar://19507384) but in seconds stored as `kCFNumberFloat32Type`.
// Frame properties example:
// {
// ColorModel = RGB;
// Depth = 8;
// PixelHeight = 960;
// PixelWidth = 640;
// "{GIF}" = {
// DelayTime = "0.4";
// UnclampedDelayTime = "0.4";
// };
// }

NSDictionary *frameProperties = (__bridge_transfer NSDictionary *)CGImageSourceCopyPropertiesAtIndex(_imageSource, i, NULL);
NSDictionary *framePropertiesGIF = [frameProperties objectForKey:(id)kCGImagePropertyGIFDictionary];

// Try to use the unclamped delay time; fall back to the normal delay time.
NSNumber *delayTime = [framePropertiesGIF objectForKey:(id)kCGImagePropertyGIFUnclampedDelayTime];
if (!delayTime) {
delayTime = [framePropertiesGIF objectForKey:(id)kCGImagePropertyGIFDelayTime];
}
// If we don't get a delay time from the properties, fall back to `kDelayTimeIntervalDefault` or carry over the preceding frame's value.
const NSTimeInterval kDelayTimeIntervalDefault = 0.1;
if (!delayTime) {
if (i == 0) {
FLLog(FLLogLevelInfo, @"Falling back to default delay time for first frame %@ because none found in GIF properties %@", frameImage, frameProperties);
delayTime = @(kDelayTimeIntervalDefault);
} else {
FLLog(FLLogLevelInfo, @"Falling back to preceding delay time for frame %zu %@ because none found in GIF properties %@", i, frameImage, frameProperties);
delayTime = delayTimesForIndexesMutable[@(i - 1)];
}
}
// Support frame delays as low as `kFLAnimatedImageDelayTimeIntervalMinimum`, with anything below being rounded up to `kDelayTimeIntervalDefault` for legacy compatibility.
// To support the minimum even when rounding errors occur, use an epsilon when comparing. We downcast to float because that's what we get for delayTime from ImageIO.
if ([delayTime floatValue] < ((float)kFLAnimatedImageDelayTimeIntervalMinimum - FLT_EPSILON)) {
FLLog(FLLogLevelInfo, @"Rounding frame %zu's `delayTime` from %f up to default %f (minimum supported: %f).", i, [delayTime floatValue], kDelayTimeIntervalDefault, kFLAnimatedImageDelayTimeIntervalMinimum);
delayTime = @(kDelayTimeIntervalDefault);
} else {
FLLog(FLLogLevelInfo, @"Falling back to preceding delay time for frame %zu %@ because none found in GIF properties %@", i, frameImage, frameProperties);
delayTime = delayTimesForIndexesMutable[@(i - 1)];
}
delayTimesForIndexesMutable[@(i)] = delayTime;
} else {
skippedFrameCount++;
FLLog(FLLogLevelInfo, @"Dropping frame %zu because valid `CGImageRef` %@ did result in `nil`-`UIImage`.", i, frameImageRef);
}
// Support frame delays as low as `kFLAnimatedImageDelayTimeIntervalMinimum`, with anything below being rounded up to `kDelayTimeIntervalDefault` for legacy compatibility.
// To support the minimum even when rounding errors occur, use an epsilon when comparing. We downcast to float because that's what we get for delayTime from ImageIO.
if ([delayTime floatValue] < ((float)kFLAnimatedImageDelayTimeIntervalMinimum - FLT_EPSILON)) {
FLLog(FLLogLevelInfo, @"Rounding frame %zu's `delayTime` from %f up to default %f (minimum supported: %f).", i, [delayTime floatValue], kDelayTimeIntervalDefault, kFLAnimatedImageDelayTimeIntervalMinimum);
delayTime = @(kDelayTimeIntervalDefault);
}
delayTimesForIndexesMutable[@(i)] = delayTime;
CFRelease(frameImageRef);
} else {
skippedFrameCount++;
FLLog(FLLogLevelInfo, @"Dropping frame %zu because valid `CGImageRef` %@ did result in `nil`-`UIImage`.", i, frameImageRef);
FLLog(FLLogLevelInfo, @"Dropping frame %zu because failed to `CGImageSourceCreateImageAtIndex` with image source %@", i, _imageSource);
}
CFRelease(frameImageRef);
} else {
skippedFrameCount++;
FLLog(FLLogLevelInfo, @"Dropping frame %zu because failed to `CGImageSourceCreateImageAtIndex` with image source %@", i, _imageSource);
}
}
_delayTimesForIndexes = [delayTimesForIndexesMutable copy];
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