[Openchrome-users] XvMC status

[Daniel Kristjansson]

On Thu, 2006-08-10 at 12:14 +0200, Thomas Hellström wrote:
> Stéphane Konstantaropoulos wrote:
> >Le jeudi 10 août 2006 10:48, vous avez écrit :
> >I thought EXA allowed to accelerate Render, which is used by other things too.
> It does, but the speedup is a bit doubtful. Many render operations
> operate on very small pixmaps, and sometimes it's faster to quickly do
> it in software than to set up the texture engines and all the EXA
> infrastructure needed to do it in hardware.
This is really about using the composite extension. I've been working
on a MythTV video output method that uses composite for the OSD. I plan
on releasing it once nVidia makes their XvMC implementation compatible
with composite (It's in their roadmap but there is no ETA). It would be
really cool if it worked with VIA hardware as well. This would allow
full color alpha blended OSD with XvMC instead of the ugly 16 color
stuff we use now.

You can already get full color alpha blended OSD with XvMC on nVidia
hardware if you configure MythTV to use their XvMC to pbuffer extension,
but it is too slow to use with HDTV because of the extra copies, the
composite extension requires just one copy+composite operation, vs.
two copies in addition to the copy+composite operation.

-- Daniel