[FFmpeg-devel] [PATCH] Add wayland support for VAAPI

[wm4]

On Tue, 27 Jun 2017 14:13:56 +0200
Hardening <rdp.effort at gmail.com> wrote:

> Le 27/06/2017 à 09:54, Mark Thompson a écrit :
> > On 27/06/17 07:38, David Fort wrote:  
> >> Wayland environment became quite popular with gnome 3. This patch adds the ability to
> >> initialize the VAAPI accelerator from a wayland display.  
> > 
> > Is there some specific use-case which needs this?  The X11 support mainly exists because of old systems (*cough* Intel Media SDK *cough*) which don't support render nodes, and therefore have to connect to a DRM master device - if X11 is running then it has to use the DRI2 authentication ritual to do that.
> > 
> > Anything recent should be connecting via the render node, which allows it to be used independently of any other system and has clear control over what hardware you are using on systems with multiple possibilities.
> >   
> 
> Hi,
> 
> my final goal is to have a h264 video rendered directly in a surface
> (using ffmpeg as a library). If render nodes surfaces can be displayed
> on the screen then I'm fine with it and forget about that patch.
> 
> I did some tests and I had the impression that when the rendering was
> done with a DRI render node, it was slower than when the VADisplay was
> grabbeb from wayland (F25 with gnome3). But it may be just an impression
> or a test bias.
> 
> Best regards.
> 

Although the hw context could create the VADisplay for you, you most
likely want to create it yourself based on your own wayland connection.
That would probably easier and more robust, because it couldn't
"accidentally" create a X or DRM VADisplay. (You can create a
AVHWDeviceContext based on an existing VADisplay.)