[MPlayer-users] fastest way to use cropdetect

[Chris Phillips]

hi,

can anyone tell me the fastest way to use cropdetect, either with mplayer 
or mencoder? initally i thought using -vo null would be fastest, but, 
understandably i suppose, the filter has no effect. Apart from just using 
simple encoding, and -nosound-ing, is there a really fast way to work out 
the cropdetect values?

thanks

chris