Angleus,
wow. This is the EXACT same issue I had ben experiencing over the
weekend. In my case, I was toyin garound w/ resizing techniques and
whenever i would input a strange resize value, I'd get this same b/w
curviture

.
.
But for me, my resolution was to just change the resizing to something
else w/in the spec ie, 704, 720, 480, 352 etc. You could also just bump
down a few notches in values.
However, if your source is permanent in this way (which I believe it
truely is

) then you'll have to recapture it (if that's even at all
possible)
Here is a suggestion, cause I've toyed w/ this one and it did actually
work for me, and may work for you too (but only if the source is not
permanently in this way)
.
.
Inside vdub, use the
Rotate - - there are two of them. In your
case, you would benefit it if you use the 2nd one, marked as
rotate2,
because you want to notch it a few increments, till it levels off w/
the proper Horizontal. And, use the Preview.
.
.
Tip.. if you enter a number, and TAB to next field (during Preview)
you can wysiwyg each try (but remember to Shift-Tab back to first field. A bit tricky to do, but can be masterd. Otherwise, it'll drive
you crazy reseting up the filter every time because you pressed the
Enter key. Just a thought.
Again, I think it's too late, as it's my belief that this is recorded
(captured) in the source this way. It's like trying to take a Black &
White video, and bust some brain cells trying to make it color..
won't happen.
Do give the above some thought though,
-vhelp