Extract Subtitles from mkv

extractMkvSubtitles.sh

#!/bin/bash
# Extract subtitles from each MKV file in the given directory

path=$PWD

echo
echo -e "\033[33mWould you like to extract subtitles from each MKV file in the directory?\033[m"
echo -e "Folder: ${path}"
echo -e "(yes/no)"
read -p ""
if [ "$REPLY" != "yes" ]; then
    echo -e '\033[38;2;255;0;0mExited by the user.\033[m'
    # https://codefather.tech/blog/exit-bash-script/
    exit
fi

# If no directory is given, work in local dir
if [ "$1" = "" ]; then
  DIR="."
else
  DIR="$1"
fi

# Get all the MKV files in this dir only
find "$DIR" -type f -maxdepth 1 -name '*.mkv' | while read filename

# Get all the MKV files in this dir and its subdirs
# find "$DIR" -type f -name '*.mkv' | while read filename
do
  # Find out which tracks contain the subtitles
  mkvmerge -J $filename | jq -r '
    .tracks |
      map((.id | tostring) + " " + .properties.language + .properties.track_name + " " + .codec) |
      join("\n")' | grep 'SubRip' | while read subline
  do
    # Grep the number of the subtitle track
    tracknumber=`echo $subline | cut -d' ' -f1`
    
    language=`echo $subline | cut -d' ' -f2`

    # Get base name for subtitle
    subtitlename="${filename%.*}.$language"

    echo Extracting: $subtitlename

    # add language check if you like e.g.:
    # if [ "$language" == "ger" ] || [ "$language" == "chiSimplified" ]; then
    mkvextract tracks "$filename" $tracknumber:"$subtitlename.srt"
    `chmod g+rw "$subtitlename.srt"`
  done
done