Convert mp4 to mp3.

mp4tomp3

#!/bin/bash

if [ $# -eq 0 -o "$1" = '-h' -o "$1" = '--help' ]; then
    echo "Usage: $0 INPUT.MP4 [...]"
    exit
fi

for input_mp4 in "$@"; do
    output_mp3=${input_mp4/.mp4/.mp3}
    ffmpeg -i "$input_mp4" -y -vn -ar 44100 -ac 2 -ab 192000 -f mp3 "$output_mp3"
done