PGS Subtitle Extraction / Resync

[Frage]

Hi,

I'm trying to merge different subtitle tracks (PGS) from two different Bluray I RIP with MakeMKV.

I have for example an UHD Disk of a movie from the USA (so Dolby Vision and 23.967 fps). I used that Bluray but I realized that the French subtitle are French Canadian.

So I double dip and also took the UHD Disk of the same movie from France (still Dolby Vision but 24 fps). MakeMKV allowed me to get two MKV and I wanted to merge the french subtitle track from the French 4K and add it to my USA 4K remux.

Sadly the FRA vs USA disk doesn't have the same frame rate and also the FRA disk has a different intro (ads). Do you have any idea how to resync ? I tried this workflow but the timecode seems off (not by a lot) and I downloaded a remux from another group who did the same job, have different result which seems more correct but I don't know why.

Open both video with Lossless Cut, check the first frame of the movie (after credits), USA is 1603, same frame on the FRA is 1879. So I did :
Source reference time = 1879 / 24 = 78,2916
Target reference time = 1603 / (24000/1001) = 66,8584
Difference is 11,433

I opened my FRA MKV with Subtitle Edit, export the subtitle to .sup.
Import the .sup for edit
Change framerate from 24 to 23.967
Adjust all subtitle to minus 11,433
Save and remux this subtitle to my USA remux

And when viewing it feels subtitle are not really in sync, maybe 0.100s / 0.200s off.

If anyone have an idea where my workflow is wrong I would appreciate it. I don't see a lot of topic about my case. I also wanted to change the subtitle color to make the FRA and USA but I finally found alone.

[dcoke22]

I wonder if it would be easier to download French .srt subtitles for the movie in question? Many playback systems support .srt subtitles as a sidecar file in the same directory as the .mkv file containing the movie.

[flojo]

Change framerate from 24 to 23.967

I thought a PGS stream was independent of the video framerate. The vanilla delay option in MKVToolNix didn't work? I used it once on a Chinese kids cartoon and it worked (at least for a 20min cartoon).

[Frage]

I wonder if it would be easier to download French .srt subtitles for the movie in question? Many playback systems support .srt subtitles as a sidecar file in the same directory as the .mkv file containing the movie.

SRT doesn't have the same style, positioning, etc, I prefer PGS over SRT any days.

[Frage]

Change framerate from 24 to 23.967

I thought a PGS stream was independent of the video framerate. The vanilla delay option in MKVToolNix didn't work? I used it once on a Chinese kids cartoon and it worked (at least for a 20min cartoon).

I actually don't know if PGS have a framerate, I think more or less yes since they have timecode based on the video.

If I check the same frame on the 24FPS movie and the 23.967FPS movie they have lets say X seconds in difference.

If I check another frame later in the movie, the Y seconds in difference isn't the same as X.

So I feels I need to do a linear resync based on a lot of frame ...
I tried resync every 100 frames, still have 2/3 frame delay on some scene (movie is The Subtance).