Creating .sup Subtitles from scratch?

[Mentar]

There have been various tools describing how existing
subtitle streams can be ripped off a DVD and then
converted to .sup for ifoedit.

Now my question is simple:

How can I generate .sup format subtitles from scratch?

I've been translating one subtitle stream into English
for a friend, but there does not seem to be a way to
generate .sup-compliant subtitles for ifoedit. So I
actually went the diehard way and used Gabest's textsub
to hardsub the video.

Isn't there ANY way to generate .sup from any text-based
subtitle format in existance?

Any help muchly appreciated!

[Doom9]

http://forum.doom9.org/showthread.php?s=&threadid=42486

[Mentar]

Nope, that's NOT it. This is still about ripping
existing subtitles off the DVD via Vobsub, but
NOT about _creating_ new ones.

I've been looking at the tool before (the tool
being SubToSup) - very hopeful - and while it's
quite useful, it does NOT allow me to create new
subtitles from a textual subs format.

[Doom9]

actually.. it is.. I'll quote my post from the other thread again.. pay special attention to the 2nd part of the last sentence:
the software page is your friend.. if you have a look at it Sub2Sup converts vobsub subtitles into the format required by ifoedit. This is the only way except for vobedit. Sub extraction in ripping programs is currently useless because these streams don't contain timestamps and there's no software to produce a .sup stream out of a textual subtitle file.

Saying there's no tool is also an answer ;)