[mythtv-users] line encoded at bottom of every frame

Chris Pinkham cpinkham at bc2va.org
Wed Oct 29 12:36:30 EST 2003


> I recently got a DCT2500 set top box and connected it to the S-Video
> input on my capture card.  But now I get a line that is 2 or 3 pixels
> thick appearing at the bottom of my screen.  It is also encoded into the
> video stream, which really messes up the commercial detection feature. 
> The line is basically white but it is not constant -- pixels change
> color.

Can't help you on the line of pixels, I think it has to do with the capture
height.  I see those occasionally on my captures as well.  I also see a 5
pixel wide black edge on the left hand side when recording at 352x480.

What I can help with is the commercial detection picking this up and thinking
the frame isn't blank.  I thought I had code in there at one time to ignore
a border X (don't remember what X was) pixels wide around the edge of the
video but it appears I dropped that accidentilly somewhere along the line.
That might explain why commercial detection sometimes misses some blank
screens when I know they were 'blank'.  I hadn't looked into it much because
for me is is mostly accurate.  Anyway, I've added code back in to ignore
the outermost X pixels when checking for whether a frame is blank or the
scene has changed.  X is set to 10 right now but I may do some tuning on that
number.  I'll get this into CVS in the next day or so when I do
my next commit.

-- 

Chris



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