high cpu usage when h265 decoding

[Willa_W_]

Dear Support,

      There are some questions:

        1.  I run the newest sample_decode.exe to decode only one h265 file and find that the cpu usage is high (as pic. 'decode_h265_hw.png' shows). 
            But the cpu usage is slow when decoding h264 file(as pic. 'decode_h264.png.png').

        sample_decode h264 -i 5_OldTownCross_1080p25.h264 -f 60 -r -wall 1 1 0 1 1 10000000 -hw -d3d11
        sample_decode h265 -i 5_OldTownCross_1080p25.h265 -f 60 -r -wall 1 1 0 1 1 10000000 -hw -d3d11

        2. The cpu usage has little difference between using -hw to decode h265 file (as pic. 'decode_h265_hw.png' shows)and using -sw to decode(as pic.'decode_h265_sw.png ').
        
        sample_decode h265 -i 5_OldTownCross_1080p25.h265 -f 60 -r -wall 1 1 0 1 1 10000000 -hw -d3d11
        sample_decode h265 -i 5_OldTownCross_1080p25.h265 -f 60 -r -wall 1 1 0 1 1 10000000 -sw -d3d11

        3. Two errors occur when decoding about 990 frames(as pic. 'decode_h265_hw_error.png' and pic. 'decode_h265_sw_error.png' show).

        4. I run the newest sample_encode.exe to encode h265 file and h264 file. And I have the same question as the first(as pic. 'encode_h264.png', pic. 'encode_h264_end.png', pic. 'encode_h265.png' and pic. 'encode_h265_end.png' show).

        Processor Type: Intel(R) Core(TM)i7-4770 CPU @ 3.40GHz 
        Operating System:Win8.1
        Media SDK: Media SDK 2014 R2 for Clients
        Media sample:Intel Media Samples 5.0.491.98719
        HEVC:Media SDK 2014 HEVC Software Pack  Evaluation and Media SDK 2014 HEVC Pack  Evaluation
        Graphics: Intel(R) HD Graphics 4600 and NVIDIA GeForce GTX 960(primary display)

        Please help me to solve these quesions. Thanks!

         Willa

[Sravanthi_K_Intel]

Hello Willa,

Our HW HEVC implementations are "hybrid", unlike H264 which use fixed-function logic. When I say hybrid, the implementation uses both CPU and GPU. That is the reason for the above-mentioned observations.

For HEVC, we use plugins for encode and decode. The default plugins that are loaded for encoder are SW plgins (this very high CPU usage). If you install the HEVC package (that comes with Pro edition), you will find the encoder plugin in the HW flavor (HW flavor -> hybrid implementation).

Hope this helps your understanding.

Regarding the failure you are observing, we need more information on the test environment and the experiment you are running (system, platform, OS, MSS version, sample/tutoral uses, input etc.,) We will need to reproduce it on our end to help you - so all this information is helpful for us.