Last few frames are dropped while decode with intel H264_qsv decoder

[Giri_b_]

Dear Anna B,

I tried to install MSS SDK on HSW system , right now i can able to triggered HW accelerators (h264_qsv decoder),

I am trying to compare decoding outputs with qsv decoder and without qsv decoder (default decoder )those two outputs are not matched..

commands used are as follows..

1) with qsv : ./ffmpeg -vcodec h264_qsv -r 30 -i input.264 -pix_fmt yuv420p output_qsv.yuv

2) with out qsv : ./ffmpeg -i input.264 output_x264.yuv ( default decoder )

these output_qsv.yuv and output_x264.yuv files are not matched..

I think that both decoders (with and with out qsv options....) should match right..?

ffmpeg version -- ffmpeg-3.0.1 downloaded from ​https://www.ffmpeg.org/download.html

This is a latest one build from source repo only..

I have faced few issues like:

i) duplicate frames are existing into the output sequence and some frames are also dropped and most of the sequences getting " 0 " th frame twice while decoding with h264_qsv decoder,
ii) few frames are also dropped into output file,
please give reply as soon as possible, please let me know any information needed..

Thanks & Regards,

[Anna_B_Intel]

Thank you for creating separate topic. Please attach output .yuv files and input h.264 stream.

Best wishes, Anna

[Giri_b_]

Dear Anna B,

Thanks for quick response,

Attached input stream and with and without qsv yuv's also,please check it once.

please let me know any information needed..

Thanks & regards,

L V Giribabu.

[Giri_b_]

Dear Anna B,

attached another test case with input h264 (CIF) and corresponding decoding yuv with and with out qsv , please look on to it once..

Thanks & regards,

L V Giribabu. 

[Giri_b_]

Dear Anna B,

I think that those two output.yuv's should match (with and with out qsv decoding yuv's), Am I correct ?

but here these two output.yuv's are not matched,due to duplicate & dropped frames are existing while decoding with Intel h264_qsv decoder..

Is there any issue with intel qsv decoder ? or Am I missing anything here ?

Regards,

L V Giribabu.

[Anna_B_Intel]

Dear Giri,

Two output decoded streams may have differences, but duplicated and dropped frames are abnormal. In this case it seems like it's FFMPEG problem, because our sample_decode doesn't duplicate and drop frames. Try to use sample_decode.

Best wishes, Anna

[Giri_b_]

Dear Anna B,

I am getting issues while decoding with H264_qsv decoder , I think that issue with Intel qsv decoder only, not in ffmpeg decoder..

Right now I have faced few issues like:

Duplicated & dropped frames are existing into the output sequence and most of the sequences getting "0 th"
   frame twice while decoding with h264_qsv decoder only,

one more thing I mentioned that :

1) output_with_qsv.yuv is a file exists with Intel h264_qsv decoder, commands used: 

  ./ffmpeg -vcodec h264_qsv -i input.264 -pix_fmt yuv420p output_with_qsv.yuv ( Intel HW h264_qsv decoder )

  --> with qsv sequence have duplicate & dropped frames are exists  while decoding with Intel h264_qsv decoder only

2) output_without_qsv.yuv is a file exists with ffmpeg decoder, command used:

./ffmpeg -i input.264 output_without_qsv.yuv ( ffmpeg decoder )

 --> here NO dropped/duplicated frames are exists ..

I tried with your sample_decode also,  it doesn't exists dropped & duplicate frames as you mentioned,

but my requirement needs to use intel h264_qsv hw accelerator only,bcs of using h264_qsv accelerators cpu utilization almost zero.. 

please help me regarding this..

Regards,

L V Giribabu.

[Anna_B_Intel]

Hi Giri,

h264_qsv and sample_decode use the same Media SDK hardware acceleration. Open source developers just integrated MSDK into FFMPEG and Intel isn't responsible for their code. So if  sample_decode works well, but h264_qsv makes duplicates and drops - the problem is in integration MSDK into FFMPEG. Please try to ask your question at FFMPEG forum. 

Best wishes, Anna

[Giri_b_]

Dear Anna B,

Thank you very much, I will try to post on FFMPEG forum...

regards,

Giri.

[Giri_b_]

Dear All,

Is any document that are related steps need to follow while configure intel qsv with LIBAV , right now I am trying to use qsv with LIBAV but unable to configure libmfx.

regards,

L V GiriBabu.

[Jeffrey_M_Intel1]

Hi Giri,

Documentation for configuring ffmpeg with libmfx is here:

https://software.intel.com/en-us/articles/accessing-intel-media-server-studio-for-linux-codecs-with-ffmpeg

More details are here:

http://www.intel.com/content/dam/www/public/us/en/documents/white-papers/quicksync-video-ffmpeg-install-valid.pdf

[Giri_b_]

Dear Jeffrey,

Thank for giving quick reply, I want to configure LIBAV with intel qsv decoder,I know how to configure qsv with ffmpeg,

my requirement need to configure intel qsv decoder with LIBAV , not ffmpeg, I am asking doc that are related to Intel qsv decoder using LIBAV open source...

Regards,

L V GiriBabu.

[Jeffrey_M_Intel1]

Hi Giri,

I'd just like to clarify -- do you mean you're looking for how to use the QSV decoder in an application using the libav API, like the example code in the doc/examples directory of ffmpeg?

[Giri_b_]

Dear Jeffrey,

Yes, exactly,I am looking for how to use the QSV decoder( -c:v H264_qsv ) in an application using the LIBAV API..

Regards,

L V Giribabu.

[Giri_b_]

Dear Jeffrey,

I tried to use the h264_qsv decoder with an application using the FFMPEG API, but few elementary streams are not decode, I am getting an issue like.. Segmentation fault,That's why I am looking alternate application using the LIBAV API..

Regards,

L V GiriBabu.