Just run script
./install.sh
If you have a single subtitle track
input_file=example.mkv output_file=subs.srt ritchie extract_subs
You can specify subtitle track by number (if multiple present). NOTE: zero-based mapping
input_file=example.mkv output_file=subs.srt subtitle=1 ritchie extract_subs
If you have both single subtitle & audio track
input_file=example.mkv ritchie burn_subs
You can specify subtitle or/and audio track by number (if multiple present). NOTE: zero-based mapping
input_file=example.mkv subtitle=1 audio=1 ritchie burn_subs