can ffmpeg use m4a file code example

Example 1: ffmpeg change audio codec from m4a to mp3

$ mkdir newfiles
$ for f in *.m4a; do ffmpeg -i "$f" -codec:v copy -codec:a libmp3lame -q:a 2 newfiles/"${f%.m4a}.mp3"; done

Example 2: ffmpeg change audio codec from m4a to mp3

ffmpeg -i "$f" -codec:v copy -codec:a libmp3lame -q:a 2 newfiles/"${f%.m4a}.mp3";