Synchronize sup/sub/idx subtitles?

[Weirdo]

I have some mkv 23.976 videos I'd like to add subtitles to, and also have subs for them on PAL DVD, but can't OCR them to .srt (SubRip gives too many errors).
I can only extract to sup or sub/idx image format. Since direct 25>23.976fps conversion won't sync them, is there a way, or tool to sync sup/sub/idx subtitles to a video, a-la Subtitle Workshop?
Subtitle Creator seems to handle these formats but I'm not sure about its synchronization capabilities.
Thanks...

[0xdeadbeef]

Hm, although I never actually tried it and always used the 24p->25p conversion instead, BDSup2Sub should also be able to do an inverse PAL-Speedup. Just set src frame rate to 25p and trg frame rate to 24p.
Subs from a different source might also need an adjustment of the global time shift. This will probably need some experimenting though to get it right.

[Weirdo]

Thanks, I will definitively try BDSup2Sub for fps conversion but I believe more "sync checkpoints" will be needed, instead of a global time shift to get it right. I was looking for a Subtitle Workshop v2.51-type solution (Menu/Edit/Timings/Adjust/Adjust Subtitles/Simple+Advanced), but it seems this just isn't possible with image-format subtitles.