我尝试使用 vImageConvert_RGB888toPlanar8 从图像中提取所有 3 个通道,然后将它们与 vImageConvert_Planar8toRGB888 一起放回原处,但图像完全搞砸了。这是为什么?
vImage_Buffer blueBuffer;
blueBuffer.data = (void*)blueImageData.bytes;
blueBuffer.width = size.width;
blueBuffer.height = size.height;
blueBuffer.rowBytes = [blueImageData length]/size.height;
vImage_Buffer rBuffer;
rBuffer.width = size.width;
rBuffer.height = size.height;
rBuffer.rowBytes = size.width;
void *rPixelBuffer = malloc(size.width * size.height);
if(rPixelBuffer == NULL)
{
NSLog(@"No pixelbuffer");
}
rBuffer.data = rPixelBuffer;
vImage_Buffer gBuffer;
gBuffer.width = size.width;
gBuffer.height = size.height;
gBuffer.rowBytes = size.width;
void *gPixelBuffer = malloc(size.width * size.height);
if(gPixelBuffer == NULL)
{
NSLog(@"No pixelbuffer");
}
gBuffer.data = gPixelBuffer;
vImage_Buffer bBuffer;
bBuffer.width = size.width;
bBuffer.height = size.height;
bBuffer.rowBytes = size.width;
void *bPixelBuffer = malloc(size.width * size.height);
if(bPixelBuffer == NULL)
{
NSLog(@"No pixelbuffer");
}
bBuffer.data = bPixelBuffer;
vImageConvert_RGB888toPlanar8(&blueBuffer, &rBuffer, &gBuffer, &bBuffer, kvImageNoFlags);
size_t destinationImageBytesLength = size.width*size.height*3;
const void* destinationImageBytes = valloc(destinationImageBytesLength);
NSData* destinationImageData = [[NSData alloc] initWithBytes:destinationImageBytes length:destinationImageBytesLength];
vImage_Buffer destinationBuffer;
destinationBuffer.data = (void*)destinationImageData.bytes;
destinationBuffer.width = size.width;
destinationBuffer.height = size.height;
destinationBuffer.rowBytes = [destinationImageData length]/size.height;
vImage_Error result = vImageConvert_Planar8toRGB888(&rBuffer, &gBuffer, &bBuffer, &destinationBuffer, 0);
NSImage* image = nil;
if(result == kvImageNoError)
{
//TODO: If you need color matching, use an appropriate colorspace here
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
CGDataProviderRef dataProvider = CGDataProviderCreateWithCFData((__bridge CFDataRef)(destinationImageData));
CGImageRef finalImageRef = CGImageCreate(size.width, size.height, 8, 24, destinationBuffer.rowBytes, colorSpace, kCGBitmapByteOrder32Big|kCGImageAlphaNone, dataProvider, NULL, NO, kCGRenderingIntentDefault);
CGColorSpaceRelease(colorSpace);
CGDataProviderRelease(dataProvider);
image = [[NSImage alloc] initWithCGImage:finalImageRef size:NSMakeSize(size.width, size.height)];
CGImageRelease(finalImageRef);
}
free((void*)destinationImageBytes);
return image;