Convert m4a (and m4b) files in current folder to mp3

m4b_to_mp3.sh

mkdir -p mp3s

SAVEIFS=$IFS
IFS=$(echo -en "\n\b")

for i in `find . -type f -iname "*.m4[ab]" -print`; do
echo $i
NAME=`echo $i | sed  -e 's/\.\///' -e  's/\.m4b//g' `
echo "doing '$NAME'"
faad --stdio $i | lame --preset standard - "mp3s/${NAME}.mp3"
done

IFS=$SAVEIFS

If you want chapters, see: https://github.com/valekhz/m4b-converter