SDWebImageDecoder.m
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/*
* This file is part of the SDWebImage package.
* (c) Olivier Poitrey <rs@dailymotion.com>
*
* Created by james <https://github.com/mystcolor> on 9/28/11.
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
#import "SDWebImageDecoder.h"
@implementation UIImage (ForceDecode)
+ (UIImage *)decodedImageWithImage:(UIImage *)image
{
CGImageRef imageRef = image.CGImage;
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
CGImageAlphaInfo alphaInfo = CGImageGetAlphaInfo(imageRef);
BOOL imageHasAlphaInfo = (alphaInfo != kCGImageAlphaNone &&
alphaInfo != kCGImageAlphaNoneSkipFirst &&
alphaInfo != kCGImageAlphaNoneSkipLast);
int bytesPerPixel = alphaInfo != kCGImageAlphaNone ? 4 : 3;
CGBitmapInfo bitmapInfo = imageHasAlphaInfo ? kCGImageAlphaPremultipliedLast : alphaInfo;
CGContextRef context = CGBitmapContextCreate(NULL,
CGImageGetWidth(imageRef),
CGImageGetHeight(imageRef),
8,
// Just always return width * bytesPerPixel will be enough
CGImageGetWidth(imageRef) * bytesPerPixel,
// System only supports RGB, set explicitly
colorSpace,
bitmapInfo);
CGColorSpaceRelease(colorSpace);
if (!context) return nil;
CGRect rect = (CGRect){CGPointZero,{CGImageGetWidth(imageRef), CGImageGetHeight(imageRef)}};
CGContextDrawImage(context, rect, imageRef);
CGImageRef decompressedImageRef = CGBitmapContextCreateImage(context);
CGContextRelease(context);
UIImage *decompressedImage = [[UIImage alloc] initWithCGImage:decompressedImageRef scale:image.scale orientation:image.imageOrientation];
CGImageRelease(decompressedImageRef);
return decompressedImage;
}
@end