[mythtv-users] PVR-250 480x480 jitter in hardware encode

[john lawler]

Hi guys,

This has been a nagging problem for me ever since I got my box setup a 
couple of months ago, but I'd forgotten about it ever since I switched 
most of my recordings to VCD (MPEG-1 352x240) mode.  However, now I want 
to record some shows and transfer them to SVCD, so I need to capture at 
the default 480x480 resolution and use nuvexport for it.

However, here's the problem.  I followed Jarod's guide almost verbatim 
(a few unimportant divergences), which means I have all the ivtv 
versions (including firmware) that he suggested and all of that, though 
I haven't done any special tweaking of that driver or anything.

Whenever I record something in 480x480, at various points during 
playback, I get this annoying tearing or jitter in the video, where a 
couple of frames tend to slide out of the picture, or something, and 
then it'll go back fine for several seconds or even a few minutes and 
then come back.

I've exported the shows using nuvexport to SVCD and played them in 
Winamp on a windows machine and I get the exact same jitter in the exact 
same points--this conclusively proves that the problem is not in 
playback on the myth box.  Thus, it must be entirely in the capture, 
which narrows things a bit.

I've already googled and searched the mailing list, of course, and I 
hear murmurs about somewhat similar issues, but nothing that sounds 
exactly the same.

I also don't have any problem with the sound sync or anything else, it's 
just those frames flickering from time to time.

So... anyone else have a similar experience?  Preferably with a 
rock-solid resolution?  I figure it probably has something to do with 
either ivtv having a slight bug in it or my configuration of ivtv.

Thanks a bunch guys,  mythtv rocks!

jl

=====
   hardware specs (for reference and posting)
=====
     Chaintech 7NIF2 mobo (get the exact BIOS date, think it's 9/xx/2003)
     on board nvidia nforce2 video (w/ shared system memory) + TVout
         + audio + net (all on board)
     Athlon-XP 2400+
     512MB PC2700 Crucial RAM
     Hauppauge PVR 250
     Western Digital 60GB hd 7200rpm

=====
   software specs
=====
     essentially identical to Jarod's guide as of about mid-March 2004.