[FFmpeg-user] Hardware accelerated decoding issue

[Chih-Wei Huang]

Hello,
I'm trying to use ffmpeg as a stagefright plugin of android-x86
to enable the hardware accelerated decoding via libva.
I'm using ffmpeg 3.1 and the latest libva and vaapi
from the master branch of Intel's repo.

Refer to the WIP branches:
https://github.com/meijjaa/android_external_ffmpeg/tree/cm-14.1-x86-n3.1.5
https://github.com/meijjaa/android_external_stagefright-plugins/tree/cm-14.1-x86_n3.1

https://github.com/cwhuang/libva
https://github.com/cwhuang/intel-vaapi-driver


Basically speaking, it works.
The video playback becomes smooth and
cpu load is lower as expected.
However, it's not stable enough.
Playback may suddenly stop.

I notice one strange log comes from ffmpeg:

04-09 21:47:13.832  1414  2860 I FFMPEG  : [h264 @ 0xb3e04400]
Hardware accelerated decoding with frame threading is known to be
unstable and its use is discouraged.


What does it mean and how to avoid that?


-- 
Chih-Wei
Android-x86 project
http://www.android-x86.org