convert AIFF to ALAC, ALAC to AAC

aiff2alac.sh

#!/bin/bash

IFS="
"

cd "${1}"
echo "source dir: "${PWD}
echo "target dir: "${2}

for input in `find . -name "*.aiff" -type f`
do
  echo "${input}"
  afconvert -f m4af -d 'alac' "${input}" "${2}/${input}.m4a"
done

alac2aac.sh

#!/bin/bash

IFS="
"

cd ${1}
echo "source dir: "${PWD}

for input in `find . -name "*.m4a"`
do  
  afconvert -v -d 'aac' -f m4af -b 128000 -o "${input%.*}.aac.m4a" "${input}"
done