[iOS] CMSampleBufferRef生成 UIImag

+ (UIImage *)lj_imageFromBuffer:(CMSampleBufferRef)buffer {
    
    CVPixelBufferRef pixelBuffer = (CVPixelBufferRef)CMSampleBufferGetImageBuffer(buffer);
    
    CIImage *ciImage = [CIImage imageWithCVPixelBuffer:pixelBuffer];
    
    CIContext *temporaryContext = [CIContext contextWithOptions:nil];
    CGImageRef videoImage = [temporaryContext createCGImage:ciImage fromRect:CGRectMake(0, 0, CVPixelBufferGetWidth(pixelBuffer), CVPixelBufferGetHeight(pixelBuffer))];
    
    UIImage *image = [UIImage imageWithCGImage:videoImage];
    CGImageRelease(videoImage);
    
    return image;
}