#!/bin/bash for line in *WMA do M4A=`echo ${line%%.*}.m4a | sed -e 'y/\ ABCDEFGHIJKLMNOPQRSTUVWXYZ\ abcdefghijklmnopqrstuvwxyz\ 0123456789()− /\ ABCDEFGHIJKLMNOPQRSTUVWXYZ\ abcdefghijklmnopqrstuvwxyz\ 0123456789()__/'` ffmpeg -y -i "${line}" -threads 8 "${M4A}" mv "${line}" bkup done