Will this work on bluray sup files?

[guilamu]

Since they are pretty much the same thing than idx/sub files...

[Vililikku]

Hi, I used first BSSup2Sub (https://github.com/mjuhasz/BDSup2Sub) and then VobSub2SRT. I think adding support for sup -> srt would not be too difficult to implement.

[QuentinBellus]

I'm also interested in this, I hope the devs can do this!

[Seegras]

Or you can use
bdsup2sub++ --language eng -o movie.idx movie.sup
Which can be found at https://aur.archlinux.org/bdsup2subpp-git.git
It works on the command line and doesn't require java.

[sperez-salgado]

Not my answer, but Anton1699's at reddit

ffmpeg -i input.mkv -map 0:s:0 -c:s dvdsub -f matroska output.mks
mkvextract output.mks tracks 0:output.sub

This requires ffmpeg and mkvtoolnix