Intel® Integrated Performance Primitives
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umc_video_dec_con NV12 scaling


Hello all,

I am using the sample application umc_video_dec_con.exe to convert a h264 video file into nv12.

Using a command such as:

umc_video_dec_con -i myfile.mp4 -f nv12 -o outfile.yuv

works as expected (verifying the output file using third party image/video viewing software).

When I introduce horizontal scaling:

umc_video_dec_con -i myfile.mp4 -f nv12 -o outfile.yuv -r 1918 1080 -k

the output file colours are not correct; it looks like a vertical stripe of nv12 (uv) colour, followed by a vertical stripe of nv21 (vu) colour, repeating.

I see the effect using any scaling factor (horizontal only, vertical works correctly).

I do not see any error when converting to rgb, yuv modes and yv12.

Is this a known issue, or am I doing something wrong?

Many thanks in advance.


Intel(R) IPP:
  ippCore 7.1.1 (r37466) Sep 24 2012 
  ippSP AVX (g9) 7.1.1 (r37466) Sep 24 2012 
  ippIP AVX (g9) 7.1.1 (r37466) Sep 24 2012 
  ippJP AVX (g9) 7.1.1 (r37466) Sep 25 2012 
  ippVC AVX (g9) 7.1.1 (r37466) Sep 25 2012 
  ippDC AVX (g9) 7.1.1 (r37466) Sep 25 2012 
  ippCC AVX (g9) 7.1.1 (r37466) Sep 25 2012 

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1 Reply

Hi J, l 

Have you try the latest IPP UMC example is in  8.0 legacy sample, you can download it  from

It looks a bug, but we are not sure as the UMC example is now legacy one,

Please note: Support for the contents of the legacy sample package is discontinued.  These previous samples are validated to build with the current IPP but no longer represent the direction of the product.  In some circumstances issues may be filed against the primitives but additional work on the samples will not be considered. 

Or  you may try Intel Media SDK
UMC vs. Media SDK ;


Best Regards,

Ying H.


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