A friend of mine who bought a tiny little player for a nephew wanted to put some videos onto it. I was asked if I knew of anywhere to get them, and since youtube has things like that, I got a couple from there. Using http://www.feelingtea.com, I downloaded the videos in FLV format. Then, using mencoder, I converted them to MP4 format with the following command:
mencoder “video.flv” -o “video.mp4” -of lavf -oac mp3lame -lameopts
abr:br=56 -ovc lavc -lavcopts vcodec=mpeg4\:vbitrate=800:mbd=2:mv0:trell:v4mv:cbp:last_pred=3 -srate 22050 -ofps 24 -vf harddup
Pretty much, this will convert video.flv to video.mp4 which you can rename to whatever you want.
I’m sure this will work on Windows with that version of mencoder, but I’ve never gave a damned to try it. Everyone has their living space, and mine’s not that.