#!/bin/bash for /R .\test %%F in (*.avi) do mencoder "%%~fF" -o "%%~dpF%%~nF_conv.mp4" -oac copy -ovc lavc -lavcopts vcodec=mpeg1video -of mpeg if exist "%%~dpF%%~nF_conv.mp4" ( del "%%~fF" ren "%%~dpF%%~nF_conv.mp4" "%%~nxF" ) done