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c++directshowlibav

How to get pixel bit count using PixelFormat in libav

Is there any way to get pixel's bit count from codecContext.pix_fmt of type PixelFormat? I do it manually using switch:

switch (OUT_IMAGE_FORMAT)
{
    case PIX_FMT_RGB24:
        pVideoInfo->bmiHeader.biBitCount = 24;
        do_something();
        break;

    //etc
}

but this requires manual updates every time libav will add or delete some pixel formats. Or if I will need to add some pixel format that wasn't supported earlier.

P.S. I need it to fill CMediaType for DirectShow filters, so bits_per_raw_sample isn't appropriate since it's for internal libav usage as I know.

Solution

  • Try using

    #include "libavutil/pixdesc.h"

pVideoInfo->bmiHeader.biBitCount =  av_get_bits_per_pixel(&av_pix_fmt_descriptors[OUT_IMAGE_FORMAT]);

    http://ffmpeg.org/doxygen/trunk/pixfmt_8h.html