The video Crop filter is designed to crop the edge off a video
frame and then pass that frame along in the FilterGraph. You set
how many pixels you want cropped from the top, bottom, left and
right edge and the filter will remove them from the frame making
the output frame smaller.
The filter properties page allow you to enter the crop settings,
if the filter is in a filter graph it will show you what the input
frame size currently is and what the new output size will be.
Some compression filters and video render filters require the
frame size to be multiples of 2, 4, 8, 16 or 32 depending on the
filter in question, you should experiment to see that results
I use this filter to crop my 488x576 capture down to 480x576
for conversion to SVCD.
Also some colour formats require multiples of 2 of colour information
is split across two pixels.
When this filter is used with Virtual VCR in the Pre Filter
Setup the properties are saved and reloaded when the Virtual VCR
application is closed and then opened again.