CVPixelBufferRef UIImage 转换

- (UIImage *)imageFromPixelBuffer:(CVPixelBufferRef)pixelBufferRef {
    CVImageBufferRef imageBuffer =  pixelBufferRef;
    
    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;
}





- (CVPixelBufferRef) pixelBufferFromCGImage: (CGImageRef) image
{
    NSDictionary *options = @{
                              (NSString*)kCVPixelBufferCGImageCompatibilityKey : @YES,
                              (NSString*)kCVPixelBufferCGBitmapContextCompatibilityKey : @YES,
                              (NSString*)kCVPixelBufferIOSurfacePropertiesKey: [NSDictionary dictionary]
                              };
    CVPixelBufferRef pxbuffer = NULL;
    
    CGFloat frameWidth = CGImageGetWidth(image);
    CGFloat frameHeight = CGImageGetHeight(image);
    
    CVReturn status = CVPixelBufferCreate(kCFAllocatorDefault,
                                          frameWidth,
                                          frameHeight,
                                          kCVPixelFormatType_32BGRA,
                                          (__bridge CFDictionaryRef) options,
                                          &pxbuffer);
    
    NSParameterAssert(status == kCVReturnSuccess && pxbuffer != NULL);
    
    CVPixelBufferLockBaseAddress(pxbuffer, 0);
    void *pxdata = CVPixelBufferGetBaseAddress(pxbuffer);
    NSParameterAssert(pxdata != NULL);
    
    CGColorSpaceRef rgbColorSpace = CGColorSpaceCreateDeviceRGB();
    
    CGContextRef context = CGBitmapContextCreate(pxdata,
                                                 frameWidth,
                                                 frameHeight,
                                                 8,
                                                 CVPixelBufferGetBytesPerRow(pxbuffer),
                                                 rgbColorSpace,
                                                 (CGBitmapInfo)kCGImageAlphaNoneSkipFirst);
    NSParameterAssert(context);
    CGContextConcatCTM(context, CGAffineTransformIdentity);
    CGContextDrawImage(context, CGRectMake(0,
                                           0,
                                           frameWidth,
                                           frameHeight),
                       image);
    CGColorSpaceRelease(rgbColorSpace);
    CGContextRelease(context);
    
    CVPixelBufferUnlockBaseAddress(pxbuffer, 0);
    
    return pxbuffer;
}




//other

- (UIImage *)convert:(CVPixelBufferRef)pixelBuffer {
    CIImage *ciImage = [CIImage imageWithCVPixelBuffer:pixelBuffer];

    CIContext *temporaryContext = [CIContext contextWithOptions:nil];
    CGImageRef videoImage = [temporaryContext
        createCGImage:ciImage
             fromRect:CGRectMake(0, 0, CVPixelBufferGetWidth(pixelBuffer), CVPixelBufferGetHeight(pixelBuffer))];

    UIImage *uiImage = [UIImage imageWithCGImage:videoImage];
    CGImageRelease(videoImage);

    return uiImage;
}