[MPlayer-users] encoding at faster speed

[Art]

I would like to encode a video lecture downloaded from the web to play
at about 1.5 times the speed. The device I playback on has no way to
change the speed of playback, as with mplayer -speed, which works
perfectly for fast playback on my work desktop. Is there a way to do
this with mencoder? Or other software? These lectures are painful to
watch at regular speed.

Can someone also tell me how to increase the coding volume? I am new
to this. The below is the encoding command I use:

mencoder -quiet -vf scale=320:240 $1 -o $2 -of avi -ofps 15 -ovc lavc
-oac mp3lame -lavcopts
vcodec=mpeg4:vbitrate=230:acodec=mp3:abitrate=64

Thanks,
Art.