Convert RMVB To AVI Using LINUX Mencoder

In terminal just type this command

mencoder in.rmvb -oac mp3lame -lameopts preset=128 -ovc lavc -lavcopts vcodec=mpeg4:vbitrate=1200 -ofps 25 -of avi -o out.avi

in.rmvb means input file name
out.avi means output file name..

Hope this will work for you all..Thanks.