Batch sync ASS subtitles according to frames

[Pierrou]

Hi, I've a lot of ASS subtitles I would like to sync to another video.
Unfortunately, they all are 24 frames late. How can I batch sync them with x frames instead of time codes? (The framerates of the videos are the same)

Subtitle Edit can batch sync but only with time codes (and it's not accurate)
Aegisub can sync according to frames but can't batch…

I digged into github and I only found softs that use time codes instead of frames.

Thank you!

[rainmasterrr]

If it's constantly 24 frames late, can you not calculate how long 24 frames take and use that value to shift, i.e. 270ms assuming 90fps?

[Pierrou]

Well I thought about that too but I guess it's not a constant framerate… (the videos are in 23.976fps)

Because with Aegisub, if I move the line with 24 more frames, the times codes for beginning and end of line are not moved from the same amount of ms… Like for example the beginning of the line is moved by 900ms and the end 1120.
But if I use frames, its 24 frames at the beginning and at the end of the line

[rainmasterrr]

From your description of the problem, perhaps you can try Linear Shift here. It may or may not fix the problem. I never used Aegisub myself, so not too familiar with the "frames" you're talking about.