ffmpeg to extract audio streams from video file according to language with different codecs

extract_audio_lang.sh

for FILE in *.mkv; do \
  echo "$FILE"; \
  for STREAM in $(ffprobe "$FILE" -loglevel error -show_entries stream=index:stream_tags=language -select_streams a -of compact=p=0:nk=1); do \
    export STREAM_ID=$(( $(echo "$STREAM" | cut -d'|' -f1)-1 )); \
    export STREAM_LANG="$(echo "$STREAM" | cut -d'|' -f2)"; \
    export STREAM_CODEC="$(ffprobe "$FILE" -loglevel error -select_streams a:"$STREAM_ID" -show_entries stream=codec_name -of csv=p=0)"; \
    mkdir -p "$STREAM_LANG"; \
    ffmpeg -hide_banner -loglevel error -y -i "$FILE" -map 0:a:m:language:"$STREAM_LANG" -vn -sn -c:a copy -map_metadata 0 ./"$STREAM_LANG"/"$(base "$FILE").$STREAM_LANG.$STREAM_CODEC"; \
  done; \
done