: CGBitmapContextCreate: unsupported parameter combination: set CGBITMAP_CONTEXT_LOG_ERRORS environmental variable to see the details: CGContextDrawImage: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable. 怎么老是报这个错呢？
CGContextRef context = CGBitmapContextCreate(data, imageSize.width, imageSize.height, 8, 4 * imageSize.width, colorSpaceRef, kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big);
最后一个参数