Wrap raw AAC files in MP4 container and copy ID3v2 tags to MP4 metadata

wrap.sh

#!/bin/bash

# Wrap raw AAC files in MP4 container and copy ID3v2 tags to MP4 metadata. Original files are not touched, new files appear besides them with .m4a extension

# requires MP4Box and kid3 (install via homebrew. You may need to install MP4Box manually from http://gpac.wp.mines-telecom.fr/downloads/gpac-nightly-builds/. Homebrew had troubles installing mp4box. The executable is found inside the osmo4.app, see below)
# kid3 also has problems with full qualified filepaths as well as spaces in the filenames

for fic in Music/**/*.aac
do
  echo processing $fic

  extension="${fic##*.}"
  filename=$(basename "$fic")  
  fullname="${fic%.*}"

#  echo has extension ${extension}   
#  echo has name ${filename}
#  echo has fullname ${fullname}
 
  rm convertaac2m4a.* 2>/dev/null
  rm "$fullname.m4a" 2>/dev/null

  cp "${fic}" convertaac2m4a.aac 
  /Applications/Osmo4.app/Contents/MacOS/MP4Box -add "$fic#audio" convertaac2m4a.m4a
  bash -c "/opt/homebrew-cask/Caskroom/kid3/3.1.2/kid3.app/Contents/MacOS/kid3-cli -c \"select convertaac2m4a.aac\" -c \"copy 2\" -c \"select convertaac2m4a.m4a\" -c \"paste 2\""
  
  cp convertaac2m4a.m4a "${fullname}.m4a"

done