I can't get it to load and the "about" isn't terribly informative, but (I think) I made a proof of concept of a similar thing. Mine is an offline video player that shows dual language subtitles. It has modes for skipping non-dialog sections, repeating the same dialog section, and slowing down playback.
What killed it, though, was a near impossibility of finding a movie that wasn't edited differently in each language (causing at least one of the audio track or language tracks to be out of sync or otherwise unmergeable). Maybe that was just an issue with Mandarin and other languages have better availability, but for me it ended up just being an endless swamp of comparing subtitle files to see if they were different, screwing around with time offsets, and eventually giving up. The player itself worked, albeit with a terrible UI, I just couldn't find more than a handful (OK, actually only one: Lost in Thailand) movies + dual sets of matching subtitle tracks to use it with.
If anybody has a solution to this I'd love to be able to use it again and even willing to post a cleaned up version if there is interest.
I also had vague thoughts of looking at the youtube API to see if there's a solution there for videos that already have multiple subtitle languages, but haven't gotten around to it yet.
What killed it, though, was a near impossibility of finding a movie that wasn't edited differently in each language (causing at least one of the audio track or language tracks to be out of sync or otherwise unmergeable). Maybe that was just an issue with Mandarin and other languages have better availability, but for me it ended up just being an endless swamp of comparing subtitle files to see if they were different, screwing around with time offsets, and eventually giving up. The player itself worked, albeit with a terrible UI, I just couldn't find more than a handful (OK, actually only one: Lost in Thailand) movies + dual sets of matching subtitle tracks to use it with.
If anybody has a solution to this I'd love to be able to use it again and even willing to post a cleaned up version if there is interest.
I also had vague thoughts of looking at the youtube API to see if there's a solution there for videos that already have multiple subtitle languages, but haven't gotten around to it yet.