图片解压缩

(UIImage *)decompressedImageWithData:(NSData *)data
{
CGImageSourceRef source = CGImageSourceCreateWithData((__bridge CFDataRef)data, NULL);
CGImageRef cgImage = CGImageSourceCreateImageAtIndex(source, 0, (__bridge CFDictionaryRef)@{(id)kCGImageSourceShouldCacheImmediately: @YES});

UIImage *image = [UIImage imageWithCGImage:cgImage];
CGImageRelease(cgImage);
CFRelease(source);
return image;
}