[mythtv-users] garbage at the top of the picture

[Michael T. Dean]

On 03/28/2006 01:44 PM, Andrew Heath wrote:

> Yeah, over/underscan can be adjusted in the xorg.conf, but that would 
> take 1/4" from the other capture card/receiver which is ok..   If I 
> swap S-video cables on my sat boxes, the garbage line goes to the 
> other card, so this tells me the s-video signal is not quite right 
> from this replacement receiver.


Actually, I would venture a guess that the receiver is outputting video 
that's completely within spec.  One of my DISH receivers outputs a 
signal with "a bit of a black bar" (it's about 1" tall on my 67" TV or 
1/4" on my laptop's 15.4" widescreen).  The other has image from the top 
to the bottom of the signal.  Both are good signals that, when plugged 
directly into the TV, show image from top to bottom of the screen.

>   I didn't know if there was an easy was to slightly crop one capture 
> card or not.


No.  Not at all.  Overscan is the right answer (the one that was 
designed by the industry to solve the issue).  And, yes, I realize that 
means you'll lose some image when watching recordings from the other 
card, but it's image you're supposed to lose (it wasn't designed to be 
shown because TV was designed to have overscan.

> I could move to the composite which looks ok, but hate to drop 
> svideo.  I would assume that composite would be better than coax though.


Definitely better than RF modulated output (on coax).  I still use 
S-Video, though, but ignore the black bar at the top.  It's harder to do 
with garbage, so you'll probably want to overscan if you stick with S-Video.

Mike