OK, trying to convert DIVX video at a size of 576x240 into DVD (at 720x480). I'm wanting to use the ffmpeg codec instead of "Decode with Quicktime" in order to speed along the transcoding, but I can't for the life of me figure out which "Letterbox" settings to use.

I figure I've got 576 pixels horizontally in the source file, and I need 720, therefore (720-576) / 2 = 72. Vertically, I've already got 240, and I need 480, therefore (480-240) / 2 = 120.

Therefore, I'm entering 120 (top), 120 (bottom), 72 (left), and 72 (right). However, my video is not looking right, as it is missing some at the top and bottom...

Can anyone help me figure out the right settings for this video? Thanks!