[mythtv-users] Jerky panning all cards and resolutions. Thoughts on where to look?

[Daniel Kristjansson]

On Mon, 2007-05-14 at 16:32 -0400, William Munson wrote:
> Hi Listland,
> 
> Since day one I have noticed that panning scenes have a distinct 
> "gallop". This is independent of video mode, resolution, signal source, 
> real time setting or rendering method. On about a 1/2 to 1 second cycle 
> the pan will speed up and slow down in a repeating pattern. Nothing I 
> have tried has fixed the problem. I dont think this is related to cpu 
> usage as it happens even when playing SD which results in an average 
> usage of about 12%. HD playback is 50-55% usage. The box is a dedicated 
> myth system with a 2.8GHz AthlonXP mobile with plenty of memory. Signal 
> sources are 2 pvr-250's and a HDHR. Video card is a NVidia FX5200 using 
> the standard VGA output to drive my HD monitor. This has happened since 
> myth 0.19 and is present in 0.20, 0.20.1 and SVN so I doubt its myth 
> itself. Any suggestions on what else to check?

It is probably your V-Sync method. Try OpenGL V-Sync and make sure you
disable "Sync To VBlank" in nvidia-settings for both
the "Video Texture Adaptor" and the "Video Blitter Adaptor"
under "X Server XVideo Settings". If that doesn't work try the
other V-Sync methods, but make sure the "Sync To VBlank"
settings are enabled.

-- Daniel