[mythtv-users] XvMC Angst with 0.20 on Ubuntu with GeForce FX5200

[Sam Hathaway]

On Oct 7, 2006, at 4:47 PM, Sam Hathaway wrote:


> The problem is, playback is slow and choppy, sound cuts in and out,
> and I get these messages (with --verbose playback on):
>
> 2006-10-07 12:02:46.352 WriteAudio: buffer underrun
> 2006-10-07 12:02:46.588 NVP: Video is 3.51891 frames behind audio
> (too slow), skipping A/V wait.
> 2006-10-07 12:02:46.696 NVP: Video is 4.02533 frames behind audio
> (too slow), skipping A/V wait.
> 2006-10-07 12:02:46.804 NVP: Video is 4.39013 frames behind audio
> (too slow), skipping A/V wait.
> 2006-10-07 12:02:46.912 NVP: Video is 4.64874 frames behind audio
> (too slow), skipping A/V wait.
> 2006-10-07 12:02:47.004 NVP: Video is 3.62141 frames behind audio
> (too slow), skipping A/V wait.
> 2006-10-07 12:02:47.104 NVP: Video is 3.2855 frames behind audio (too
> slow), skipping A/V wait.
>
> These repeat continuously for the duration of playback. This is with
> 1080i ATSC source material. I'm pretty sure it's not the CPU -- CPU
> usage is under 50%.
>

More information: I've since tried playing back SD programs (480i I  
think) with XvMC enabled, and it looks fine, with no errors in the  
log. I haven't been able to find any 780p content to test, but I have  
tried playing back DVDs with the Internal player, and I get the same  
problems as with 1080i.

After playing with it some more, I've noticed that the video is not  
only choppy, but is playing back much slower than it should be.

I remember seeing something a while ago maybe about the bandwidth  
required by 1080i XvMC being too much for the AGP bus or something,  
but I can't find it now. Does that sound familiar? Are there any BIOS  
setting that could make a difference?

Thanks.
-sam