[mythtv-users] Not enough processing power causing HD video to stutter or jitter?

[Jonathan Rogers]

On Sun, 2007-02-11 at 15:06 +0000, Stroller wrote:
> On 11 Feb 2007, at 06:13, MythTV wrote:
> > Because I haven't installed the video software, I questioned whether
> > Xvid was running on the video card.  Everyone says Xvid should be
> > turned on for better MPEG performance, but I can't find a web site to
> > tell me how to turn it on.  Can someone point the way for me?
> 
> Um... are you sure you don't mean XvMC?

He's probably is talking about Xorg's XVIDEO extension (abbreviated Xv),
which is essential to video playback when using any type of driver. XvMC
is itself an extension to Xv. While Xv is essential, especially for HD
video, XvMC is not, provided one has a fast enough CPU. For instance,
I'm using a Radeon 9600 with Xorg's Free radeon driver, which implements
Xv.

Xorg's Free "nv" driver for Nvidia cards may be good enough for playback
of HD on a Pentium 4 3.2GHz system, though it won't provide OpenGL
acceleration. I suspect the problem is that a generic driver such as
vesa is being used, which doesn't accelerate XVIDEO at all. Xorg's
configuration file (usually /etc/X11/xorg.conf), it's log
(usually /var/log/Xorg.0.log) and the output from mythfrontend may
provide clues to the problem.

Jonathan Rogers