iOS UIImage和CVPixelBuffer互相转换

培根芝士2023-10-14 15:46

UIImage转CVPixelBuffer

objectivec 复制代码

+ (CVPixelBufferRef)pixelBufferFromCGImage:(CGImageRef)image {
    NSDictionary *options = [NSDictionary dictionaryWithObjectsAndKeys:
                             [NSNumber numberWithBool:true], kCVPixelBufferCGImageCompatibilityKey,
                             [NSNumber numberWithBool:true], kCVPixelBufferCGBitmapContextCompatibilityKey, nil];
    CVPixelBufferRef pxbuffer = NULL;
    size_t width = CGImageGetWidth(image);
    size_t height = CGImageGetHeight(image);
    CVReturn status = CVPixelBufferCreate(kCFAllocatorDefault, width, height, kCVPixelFormatType_32BGRA, (__bridge CFDictionaryRef)options, &pxbuffer);
    if (status != kCVReturnSuccess) {
        NSLog(@"CVPixelBufferCreate Fail");
    }
    CVPixelBufferLockBaseAddress(pxbuffer, 0);
    void *pxdata = CVPixelBufferGetBaseAddress(pxbuffer);
    
    CGColorSpaceRef rgbColorSpace = CGColorSpaceCreateDeviceRGB();
        
    CGContextRef context = CGBitmapContextCreate(pxdata, width, height, 8, CVPixelBufferGetBytesPerRow(pxbuffer), rgbColorSpace, (CGBitmapInfo)kCGImageAlphaNoneSkipFirst);
    
    CGContextDrawImage(context, CGRectMake(0, 0, width, height), image);
    CVPixelBufferUnlockBaseAddress(pxbuffer, 0);
    
    CGColorSpaceRelease(rgbColorSpace);
    CGContextRelease(context);
    
    return pxbuffer;
}

CVPixelBuffer转UIImage

objectivec 复制代码

+ (UIImage *)imageFromPixelBuffer:(CVPixelBufferRef)pixelBuffer {
    CVImageBufferRef imageBuffer =  pixelBuffer;
        
    CVPixelBufferLockBaseAddress(imageBuffer, 0);
    void *baseAddress = CVPixelBufferGetBaseAddress(imageBuffer);
    size_t width = CVPixelBufferGetWidth(imageBuffer);
    size_t height = CVPixelBufferGetHeight(imageBuffer);
    size_t bufferSize = CVPixelBufferGetDataSize(imageBuffer);
    size_t bytesPerRow = CVPixelBufferGetBytesPerRowOfPlane(imageBuffer, 0);
    
    CGColorSpaceRef rgbColorSpace = CGColorSpaceCreateDeviceRGB();
    CGDataProviderRef provider = CGDataProviderCreateWithData(NULL, baseAddress, bufferSize, NULL);
    
    CGImageRef cgImage = CGImageCreate(width, height, 8, 32, bytesPerRow, rgbColorSpace, kCGImageAlphaNoneSkipFirst | kCGBitmapByteOrderDefault, provider, NULL, true, kCGRenderingIntentDefault);
    UIImage *image = [UIImage imageWithCGImage:cgImage];
    CGImageRelease(cgImage);
    CGDataProviderRelease(provider);
    CGColorSpaceRelease(rgbColorSpace);
    
    CVPixelBufferUnlockBaseAddress(imageBuffer, 0);
    return image;
}