[MPlayer-users] mencoder adding a border to a movie

[scott at bonnag.com]

Hi,

I want to encode and scale 16:9 films from dvd to 4:3 but preserve the aspect 
ratio.  I want the films to appear widescreen but add a black border to and 
bottom.

I have found this on the man page:
mencoder dvd://2 -vf scale -zoom -xy 512

which almost does it, but I want to add black to the top and bottom to make it 
4:3.

Any suggestions?

Thanks,

Scott