[Development] QT5.5 MultiMedia Gstreamer 1.0 Pipeline Hardware assisted Video Decode using VAAPI on Intel Platform.

[Paul Hesse]

 Hello, we built qt5.5 release version on our debian 8 system with all system deps in place. Build went fine and the qt build system is working ok.
In testing one of the QT multimedia video player examples I noticed that while it is using Gstreamer 1.0 on the backend the video backend is not doing GPU Hardware video decode so the cpu usage is high. We are using a intel Haswell based x86 platform. On this particular platform we use VAAPI to leverage the HW video decode on the intel processor.
Running some tests by command line to invoke gstreamer 1.0 to play a  mp4 video results in flawless HW assisted video decode with extremely low cpu usage.
My question, Has VAAPI calls been implemented as part of what gets passed to gstreamer so as to leverage HW video decode in QT 5.5 Multimedia ?
Is there a particular source file or files available that handle the gstreamer pipeline so we may understand the mechanics of QT's backend video playout implementation. ?
Any assistance with this would be very helpful.
Thanks Scott

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.qt-project.org/pipermail/development/attachments/20150708/df8d1a21/attachment.html>