[MPlayer-users] seeking explanation of -1 and -2 in -vop scale

[SMuelas]

> OK, so can someone actually say what d_length, prescaled and the other 
> variables actaully mean? giving an example...
> 
> a 720x576 vob, 16:9 aspect, cropped with 710:434:4:74, and then to be 
> scaled with w=640 and y to well.... be right!
> 
Do not crop to w=710. Try to find a multiple of 16, or, at least, 8.
Crop systematically to 704 as the rest is black (in Europe, don't know
in USA). But, anyway, as I have said before: IF IN DOUBT ------> 
-vop rectangle=your values for crop
and look at the film!!
and, please, finish this -1, -2 story. Someone has already indicated
where you can find the explanation...  
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