[mythtv-users] playback is smooth, yet lacking... seems like smootly missing frames

Jarod Wilson lists at wilsonet.com
Wed Jan 31 19:24:58 UTC 2007

Bill wrote:
> Sorry if this is obvious.  I am not sure what to even stfw on for something like this.  I've tried, but nothing seems to match what I would describe this as... 
> I have a 2.4ghz P4, running a pvr500, pvr350.  Output is from an nvidia fx5200 (AGP 4x) via DVI-D to an LCD TV (westinghouse).  I am outputting at 1080p.  
> My sources for video are standard tv into the tuners and recorded at 720x480. 
> Now, I am absolutley thrilled with the quality of the recordings and how well mythtv scales it up for the LCD at hi-res.
> But, it seems a little "off".  If I had to describe it, I would say that something is very smoothly and evenly dropping frames.  Not the kind of dropping where a whole handful goes away, and its noticable, but more the movements of the people on the screen just get a bit jerky... but not terribly so.  
> I am really having trouble describing this.  I guess if there is 24 frames a second, it would be dropping maybe every 5th one or something...
> Is this something that it does when it gets overworked or something?  The cpu is at about 69% during the playback.

Whoa. Shouldn't be that busy for SDTV playback. What does 'xvinfo' 
(while in an xterm on your display, or logged in via ssh as your X user 
following an export DISPLAY=:0) say? With some nvidia cards and the 
nvidia driver, if the x composite extension gets enabled, xvideo WON'T 
get enabled. Easily fixed by tacking a few lines onto the end of your 
xorg.conf though:

Section "Extensions"
     Option "Composite" "Disable"

> I want to try Xvmc tonight to see if I can get it down a bit, and hopefully the picture wont suffer.

Absolutely no reason you should ever need xvmc for sdtv.

> Can anyone tell me:
> 1) What to call this so I can stfw more effectively


> 2) Tell me I am not crazy

Still possible. :)

> 3) Is this a feature of an LCD?

Definitely not.


More information about the mythtv-users mailing list