Is it possible to extract subtitles only from 4k/standard blu ray disc?

[MacGyver221]

I am completely fine with playing my blu ray discs(including 4k) but in order to translate subtitles I need to extract them. It seems pointless to process whole 4k video so I would be interested in extracting subtitles only(my assumption is that it would take just few minutes of time and few Mb of memory). Is this possible with makeMKV? If not is there anything else I can do?

Once extracted and translated I could pass subtitles to my player through USB

[Woodstock]

Not with MakeMKV. The subtitle tracks are interspersed with the video and audio tracks, so you're going to have to scan the whole disk to extract JUST the subtitle tracks anyway.

[MacGyver221]

Not with MakeMKV. The subtitle tracks are interspersed with the video and audio tracks, so you're going to have to scan the whole disk to extract JUST the subtitle tracks anyway.

So it takes roughly similar amount of time to extract subtitles alone as it would be to have full quality 4k rip?

[Woodstock]

Yes. It's just the way the pieces are integrated into the disk, with everything part of a "single file"... although sometimes it's a collection of files.

My copy of Riselmine is a real mess, which was easier to simply rip it as one very long episode, then use handbrake to break it into separate ones. Trying to extract JUST the subtitles from the disk itself would not save any time vs. ripping everything and splitting it up.

[MacGyver221]

Thanks for detailed answer! Are you aware of any alternative that might interest me for my use case?

[Woodstock]

Personally, I use mkvtoolnix for splitting files if I'm not going to encode them, but I use handbrake if I want them smaller. If disks don't have a lot of swapping around, handbrake is fine.

But, what you've described is best handled with mkvtoolnix to break out the subtitle tracks, as well as splicing in your re-done subtitles. It has tools to pull specific tracks out, and merge multiple files together. Eons ago, I would pull subtitles from DVD versions of disks, and merge them with the Bluray versions, when I didn't have players that could display PGS subtitles.