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Fix the issue when WebP Encoding grayscale image/CMYK image #53

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Merged
merged 4 commits into from
Feb 2, 2021
Merged

Fix the issue when WebP Encoding grayscale image/CMYK image #53

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cab8cd9
Fix the issue when WebP Encoding grayscale image with only 1 channel,…
dreampiggy Feb 1, 2021
6693ecb
Added the test case `testEncodingGrayscaleImage` about grayscale
dreampiggy Feb 1, 2021
777065d
Fix the similiar case when input image is CMYK image, check color spa…
dreampiggy Feb 1, 2021
1903ac2
Fix again for CMYK image
dreampiggy Feb 1, 2021
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34 changes: 22 additions & 12 deletions SDWebImageWebPCoder/Classes/SDImageWebPCoder.m
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Original file line number Diff line number Diff line change
Expand Up @@ -736,6 +736,9 @@ - (nullable NSData *)sd_encodedWebpDataWithImage:(nullable CGImageRef)imageRef
}

size_t bytesPerRow = CGImageGetBytesPerRow(imageRef);
size_t bitsPerComponent = CGImageGetBitsPerComponent(imageRef);
size_t bitsPerPixel = CGImageGetBitsPerPixel(imageRef);
size_t components = bitsPerPixel / bitsPerComponent;
CGBitmapInfo bitmapInfo = CGImageGetBitmapInfo(imageRef);
CGImageAlphaInfo alphaInfo = bitmapInfo & kCGBitmapAlphaInfoMask;
CGBitmapInfo byteOrderInfo = bitmapInfo & kCGBitmapByteOrderMask;
Expand Down Expand Up @@ -763,10 +766,15 @@ - (nullable NSData *)sd_encodedWebpDataWithImage:(nullable CGImageRef)imageRef
if (!dataRef) {
return nil;
}
// Check colorSpace is RGB/RGBA
CGColorSpaceRef colorSpace = CGImageGetColorSpace(imageRef);
BOOL isRGB = CGColorSpaceGetModel(colorSpace) == kCGColorSpaceModelRGB;

uint8_t *rgba = NULL; // RGBA Buffer managed by CFData, don't call `free` on it, instead call `CFRelease` on `dataRef`
// We could not assume that input CGImage's color mode is always RGB888/RGBA8888. Convert all other cases to target color mode using vImage
if (byteOrderNormal && ((alphaInfo == kCGImageAlphaNone) || (alphaInfo == kCGImageAlphaLast))) {
BOOL isRGB888 = isRGB && byteOrderNormal && alphaInfo == kCGImageAlphaNone && components == 3;
BOOL isRGBA8888 = isRGB && byteOrderNormal && alphaInfo == kCGImageAlphaLast && components == 4;
if (isRGB888 || isRGBA8888) {
// If the input CGImage is already RGB888/RGBA8888
rgba = (uint8_t *)CFDataGetBytePtr(dataRef);
} else {
Expand All @@ -775,10 +783,11 @@ - (nullable NSData *)sd_encodedWebpDataWithImage:(nullable CGImageRef)imageRef
vImage_Error error = kvImageNoError;

vImage_CGImageFormat srcFormat = {
.bitsPerComponent = (uint32_t)CGImageGetBitsPerComponent(imageRef),
.bitsPerPixel = (uint32_t)CGImageGetBitsPerPixel(imageRef),
.colorSpace = CGImageGetColorSpace(imageRef),
.bitmapInfo = bitmapInfo
.bitsPerComponent = (uint32_t)bitsPerComponent,
.bitsPerPixel = (uint32_t)bitsPerPixel,
.colorSpace = colorSpace,
.bitmapInfo = bitmapInfo,
.renderingIntent = CGImageGetRenderingIntent(imageRef)
};
vImage_CGImageFormat destFormat = {
.bitsPerComponent = 8,
Expand All @@ -793,14 +802,15 @@ - (nullable NSData *)sd_encodedWebpDataWithImage:(nullable CGImageRef)imageRef
return nil;
}

vImage_Buffer src = {
.data = (uint8_t *)CFDataGetBytePtr(dataRef),
.width = width,
.height = height,
.rowBytes = bytesPerRow
};
vImage_Buffer dest;
vImage_Buffer src;
error = vImageBuffer_InitWithCGImage(&src, &srcFormat, nil, imageRef, kvImageNoFlags);
if (error != kvImageNoError) {
vImageConverter_Release(convertor);
CFRelease(dataRef);
return nil;
}

vImage_Buffer dest;
error = vImageBuffer_Init(&dest, height, width, destFormat.bitsPerPixel, kvImageNoFlags);
if (error != kvImageNoError) {
vImageConverter_Release(convertor);
Expand Down
Binary file added Tests/Images/TestImageGrayscale.jpg
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29 changes: 29 additions & 0 deletions Tests/SDWebImageWebPCoderTests.m
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Original file line number Diff line number Diff line change
Expand Up @@ -292,6 +292,35 @@ - (void)testEncodingSettingsIncorrectType {
expect(config.method).to.equal(4);
}


- (void)testEncodingGrayscaleImage {
NSURL *grayscaleImageURL = [[NSBundle bundleForClass:[self class]] URLForResource:@"TestImageGrayscale" withExtension:@"jpg"];
NSData *grayscaleImageData = [NSData dataWithContentsOfURL:grayscaleImageURL];
UIImage *grayscaleImage = [[UIImage alloc] initWithData:grayscaleImageData];
expect(grayscaleImage).notTo.beNil();

NSData *webpData = [SDImageWebPCoder.sharedCoder encodedDataWithImage:grayscaleImage format:SDImageFormatWebP options:nil];
expect(webpData).notTo.beNil();

UIImage *decodedImage = [UIImage sd_imageWithData:webpData];
expect(decodedImage).notTo.beNil();

// Sample to verify that encoded WebP image's color is correct.
// The wrong case before bugfix is that each column color will repeats 3 times.
CGPoint point1 = CGPointMake(271, 764);
CGPoint point2 = CGPointMake(round(point1.x + decodedImage.size.width / 3), point1.y);
UIColor *color1 = [decodedImage sd_colorAtPoint:point1];
UIColor *color2 = [decodedImage sd_colorAtPoint:point2];
CGFloat r1, r2;
CGFloat g1, g2;
CGFloat b1, b2;
[color1 getRed:&r1 green:&g1 blue:&b1 alpha:nil];
[color2 getRed:&r2 green:&g2 blue:&b2 alpha:nil];
expect(255 * r1).notTo.equal(255 * r2);
expect(255 * g1).notTo.equal(255 * g2);
expect(255 * b1).notTo.equal(255 * b2);
}

@end

@implementation SDWebImageWebPCoderTests (Helpers)
Expand Down
4 changes: 4 additions & 0 deletions Tests/SDWebImageWebPCoderTests.xcodeproj/project.pbxproj
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Original file line number Diff line number Diff line change
Expand Up @@ -9,6 +9,7 @@
/* Begin PBXBuildFile section */
0EF5B6264833B7BC20894578 /* Pods_SDWebImageWebPCoderTests.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 46F21AD7D1692EBAC4D0FF33 /* Pods_SDWebImageWebPCoderTests.framework */; };
3219F3B2228B0453003822A6 /* TestImageBlendAnimated.webp in Resources */ = {isa = PBXBuildFile; fileRef = 3219F3B1228B0453003822A6 /* TestImageBlendAnimated.webp */; };
325E268E25C82BE1000B807B /* TestImageGrayscale.jpg in Resources */ = {isa = PBXBuildFile; fileRef = 325E268D25C82BE1000B807B /* TestImageGrayscale.jpg */; };
808C918E213FD131004B0F7C /* SDWebImageWebPCoderTests.m in Sources */ = {isa = PBXBuildFile; fileRef = 808C918D213FD131004B0F7C /* SDWebImageWebPCoderTests.m */; };
808C919C213FD2B2004B0F7C /* TestImageStatic.webp in Resources */ = {isa = PBXBuildFile; fileRef = 808C919A213FD2B2004B0F7C /* TestImageStatic.webp */; };
808C919D213FD2B2004B0F7C /* TestImageAnimated.webp in Resources */ = {isa = PBXBuildFile; fileRef = 808C919B213FD2B2004B0F7C /* TestImageAnimated.webp */; };
Expand All @@ -17,6 +18,7 @@
/* Begin PBXFileReference section */
28D8AA3D3015E075692FD3E3 /* Pods-SDWebImageWebPCoderTests.debug.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-SDWebImageWebPCoderTests.debug.xcconfig"; path = "../Pods/Target Support Files/Pods-SDWebImageWebPCoderTests/Pods-SDWebImageWebPCoderTests.debug.xcconfig"; sourceTree = "<group>"; };
3219F3B1228B0453003822A6 /* TestImageBlendAnimated.webp */ = {isa = PBXFileReference; lastKnownFileType = file; path = TestImageBlendAnimated.webp; sourceTree = "<group>"; };
325E268D25C82BE1000B807B /* TestImageGrayscale.jpg */ = {isa = PBXFileReference; lastKnownFileType = image.jpeg; path = TestImageGrayscale.jpg; sourceTree = "<group>"; };
46F21AD7D1692EBAC4D0FF33 /* Pods_SDWebImageWebPCoderTests.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = Pods_SDWebImageWebPCoderTests.framework; sourceTree = BUILT_PRODUCTS_DIR; };
808C918B213FD130004B0F7C /* SDWebImageWebPCoderTests.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; includeInIndex = 0; path = SDWebImageWebPCoderTests.xctest; sourceTree = BUILT_PRODUCTS_DIR; };
808C918D213FD131004B0F7C /* SDWebImageWebPCoderTests.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = SDWebImageWebPCoderTests.m; sourceTree = "<group>"; };
Expand Down Expand Up @@ -78,6 +80,7 @@
808C9199213FD2B2004B0F7C /* Images */ = {
isa = PBXGroup;
children = (
325E268D25C82BE1000B807B /* TestImageGrayscale.jpg */,
808C919A213FD2B2004B0F7C /* TestImageStatic.webp */,
808C919B213FD2B2004B0F7C /* TestImageAnimated.webp */,
3219F3B1228B0453003822A6 /* TestImageBlendAnimated.webp */,
Expand Down Expand Up @@ -154,6 +157,7 @@
3219F3B2228B0453003822A6 /* TestImageBlendAnimated.webp in Resources */,
808C919D213FD2B2004B0F7C /* TestImageAnimated.webp in Resources */,
808C919C213FD2B2004B0F7C /* TestImageStatic.webp in Resources */,
325E268E25C82BE1000B807B /* TestImageGrayscale.jpg in Resources */,
);
runOnlyForDeploymentPostprocessing = 0;
};
Expand Down