[mythtv-users] XvMC - Nvidia isssues?

[David Corder]

On Sunday, January 22, 2006, at 07:11AM, Dan Seddon <dan.seddon at framestore-cfc.com> wrote:

>Yup - colour menus are nice ; ) Though, I do find XvMC is smoother 
>generally with my machine + HDTV is imminant in the UK and I don't fancy 
>my chances of getting it to run on my current CPU without a leg-up from 
>my video card.... I've just been glancing at a few options in the Nvidia 
>help though and I noticed this hidding in what seems like the wrong section:
>
>|Option "XvmcUsesTextures" "boolean"|
>
>    Forces XvMC to use the 3D engine for XvMCPutSurface requests rather
>    than the video overlay. Default: false (video overlay is used when
>    available).
>
>Could be of use for getting the menus not to jitter (on non-quadro) and 
>maybe in colour too..... There is also CIOverlay (indexed colour) but I 
>couldn't get that to do anything : (
>
>Thanks for your help!
>
>Dan

I just wanted to chime in:

After using MythTV for nearly two years, I moved to an apartment where I didn't have cable. I've moved again and now have cable, so this past weekend I got my MythTV box (and LAN fileserver) back up and running. I'm running Gentoo with a 2.6.15-gentoo-r1 kernel. After much tinkering, I am down to just a few minor issues. One of them was the video jitter when menus and other OSD elements were displayed and Xvmc was enabled (I have a GeForce FX 5200 driving my Samsung 30" CRT HDTV with a 540p signal via a DVI-HDMI cable). Disabling Xvmc was not an option, as this is only a lowly Athlon XP 2500+ (overclocked to 2.0 GHz) with two PVR-250 cards and a FusionHD 5 Lite card on the way to replace a PVR-250.

I spent a couple hours wrestling with this issue last night, trying various nVidia driver settings (I had noticed it originally with the 6629 drivers, jumped straight to the latest 8178 drivers in Portage and still had the issue, so apparently it's not the >7676 issue with OpenGL Vsync others have mentioned). I played with nearly every option in nvidia-settings to no avail. I tried nearly every OSD-related setting I could find in the front end settings without success. Finally I stumbled upon this thread and this driver option. Adding the following line to my "Device" section in /usr/X11/xorg.conf completely solved the jitter w/OSD issue I was having:

Option "XvmcUsesTextures" "true"

So nice to be able to pause TV, schedule recordings, and skip commercials again (after a few months with just regular cable, I still find myself watching the commercials because I haven't yet got into the mindset that I can skip them :). Still need to fix LIRC, tweak the overscan settings, make sure MythWeb is working, replace the failing drive in my RAID array (1.04 TB RAID-5, also used as NAS; 8 Maxtor 160GB ATA/133 drives attached to a 3ware 7506-8 hardware RAID controller, but the SMART data for all the drives say they're OK, so I'm just waiting for it to actually fail completely), add the HDTV tuner card I've ordered, and replace the current sound card with one with optical S/PDIF output to connect to my AV receiver).

Thanks to all the developers for this awesome software! Lookin' forward to 0.19 (is there a list somewhere of the new features?) And thanks to Dan for pointing me towards this fix.

-Dave Corder