Accuracy problem using ass (nothing to do with sphincter)

[Sergejack]

I'm facing a problem, I made a video in 120 fps for wich I created subtitles in ASS.
But as you may know ass in only accurate to the 100th of second (100fps would still be ok).
So sometimes it display one true frame earlier or later than I want.
A true frame means that the follwing drop frames are affected (VSFilter has to work that way).

So I would like to know what I could do about it, still keeping the framerate at 120fps.

For instance : converting sub into another subtitle format ? Do something about the video ?

[ai4spam]

Wow, do you actually have a movie that plays at that frame rate, and your subtitles are appearing/disappearing fast enough that you can actually notice a few millisecond differences?
Well, use a frame-based format like MicroDVD .sub and you should be ok. The problem is, if the format in which you saved the subs is only precise up to a point, there's no conversion you can apply to make it better (you know, garbage in, garbage out).

[Liisachan]

Yeah, I noticed that problem.
Time stamps in USF is more accurate (1ms accuracy)

This is a hack for SSA that enables you to control things with 1ms accuracy:

{\1a&Hff&\3a&Hff&\4a&Hff&}{\t(t1,t2,\1a&H00&\3a&H00&\4a&H80&)}

t1 and t2 are small values (such as 1, 2, 3, ... or 9) suitable for your purpose.