On Tue, Mar 09, 2010 at 12:02:27PM -0200, Sebastián Lacuesta wrote: > mencoder AnInputFile.ext -o TheOutputFile.3gp -of lavf -oac lavc -ovc lavc > -srate 8000 -vf scale=176:144 -ofps 12 -channels 1 -lavcopts > vcodec=h263:acodec=libopencore_amrnb:abitrate=12200 Have you tried -af lavcresample=8000 instead of -srate?