I previously ripped a TV series and didn't include the subtitles. I now wish to include them (not a .srt file but the idx/sub) without having to spend the time to re-encode all the discs. Then I can simply mux them, with the mp4 files I already have, into mkv containers. I know this is easy to do on Windows but am stuck on how to extract them on a Mac. I've found 2 answers online, both of which use Avidemux, which I have installed, but I do not get the same menu under Tools which both these answers show. When I click on Tools, I only have the options on the attached pic; not those depicted in the avidemux answers (see youtube vid - ). So does anyone know of another way that I can extract the subtitles please, so I can simply mux them with my existing mp4 files?