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Editorial Team
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Asked: 2026-05-26T14:06:53+00:00

I have a TV capture card that has a feed coming in as a

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I have a TV capture card that has a feed coming in as a YUV format. I’ve seen other posts here similar to this question and attempted to try every possible method stated, but neither of them provided a clear image. At the moment the best results were with the OpenCV cvCvtColor(scr, dst, CV_YUV2BGR) function call.

I am currently unaware of the YUV format and to be honest confuses me a little bit as it looks like it stores 4 channels, but is only 3? I have included an image from the capture card to hope that someone can understand what is possibly going on that I could use to fill in the blanks.

YUV to BGR converted image

The feed is coming in through a DeckLink Intensity Pro card and being accessed in a C++ application in using OpenCV in a Windows 7 environment.

Update

I have looked at a wikipedia article regarding this information and attempted to use the formula in my application. Below is the code block with the output received from it. Any advice is greatly appreciated.

BYTE* pData;

    videoFrame->GetBytes((void**)&pData);

    m_nFrames++;

    printf("Num Frames executed: %d\n", m_nFrames);

    for(int i = 0; i < 1280 * 720 * 3; i=i+3)
    {
        m_RGB->imageData[i] = pData[i] + pData[i+2]*((1 - 0.299)/0.615);
        m_RGB->imageData[i+1] = pData[i] - pData[i+1]*((0.114*(1-0.114))/(0.436*0.587)) - pData[i+2]*((0.299*(1 - 0.299))/(0.615*0.587));
        m_RGB->imageData[i+2] = pData[i] + pData[i+1]*((1 - 0.114)/0.436);
    }

Attempted RGB conversion

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1 Answer

  1. Editorial Team

    It looks to me like you’re decoding a YUV422 stream as YUV444. Try this modification to the code you provided:

    for(int i = 0, j=0; i < 1280 * 720 * 3; i+=6, j+=4)
{
    m_RGB->imageData[i] = pData[j] + pData[j+3]*((1 - 0.299)/0.615);
    m_RGB->imageData[i+1] = pData[j] - pData[j+1]*((0.114*(1-0.114))/(0.436*0.587)) - pData[j+3]*((0.299*(1 - 0.299))/(0.615*0.587));
    m_RGB->imageData[i+2] = pData[j] + pData[j+1]*((1 - 0.114)/0.436);
    m_RGB->imageData[i+3] = pData[j+2] + pData[j+3]*((1 - 0.299)/0.615);
    m_RGB->imageData[i+4] = pData[j+2] - pData[j+1]*((0.114*(1-0.114))/(0.436*0.587)) - pData[j+3]*((0.299*(1 - 0.299))/(0.615*0.587));
    m_RGB->imageData[i+5] = pData[j+2] + pData[j+1]*((1 - 0.114)/0.436);
}

    I’m not sure you’ve got your constants correct, but at worst your colors will be off – the image should be recognizable.

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