[FFmpeg-devel] ffmpeg stuck in transcoding H264 using QSV

Ivan Uskov ivan.uskov at nablet.com
Tue Jul 26 12:08:25 EEST 2016

Hello Chao,

Tuesday, July 26, 2016, 9:04:49 AM, you wrote:

> I tried to debug it a bit by comparing ffmpeg code with intel media SDK.
> There is sth. I don't understand. Not sure whether it's related..
> In ffmpeg, we decode the frame in a loop
> <https://github.com/FFmpeg/FFmpeg/blob/master/libavcodec/qsvdec.c#L357>, it
> sleeps and retries as long as MFXVideoDECODE_DecodeFrameAsync returns busy.
> In intel media SDK sample_decode, it calls SyncOperation when
> MFXVideoDECODE_DecodeFrameAsync returns busy.

> Could this be the cause?
The documentation for MFXVideoDECODE_DecodeFrameAsync says:
Hardware device is currently busy. Call this function again in a few milliseconds.
So if documented way does not work it looks like we have issue inside SDK.
But I will try to double check sample_decode code.

By the way, what is your platform? Linux? Do you use a patched kernel
recommended by Intel for specific sdk version?

Best regards,
 Ivan                            mailto:ivan.uskov at nablet.com

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