What's the algorithm for generating the time map (VTS_TMAP) data for a DVD's IFO file?

I'm looking to 开发者_如何学Ccreate an IFO file for a VOB so that I can produce a video DVD.

I have the specifications for the contents of the VTS_01_1.IFO file however I'm not sure on how to generate the time map data for the VTS_TMAP section.

I think the entries are based on frame rate but this is not obvious from the example DVD's I've looked at.

Any help or pointers to the appropriate source would be greatly appreciated.

http://forum.videolan.org/viewtopic.php?f=32&t=76308&p=315301#p315301 is a patch describing its use.

http://dvd.sourceforge.net/dvdinfo/ifo_vts.html#tmap also lists the spec. http://www.mail-archive.com/dvdnav-discuss@mplayerhq.hu/msg01052.html also has some information, and http://forum.videolan.org/viewtopic.php?f=32&t=76308