Replacing DVD subtitles (re-authoring)

[SiS sos]

I'm trying to replace the subtitles in a DVD. I've ripped the source and everything is stored in a VIDEO_TS folder. I have also identified the IFO file containing the subtitle track that I want to replace.
My question: Is there a way to convert a subtitle track (.srt or bmp) in such a way that I can replace some files in the VIDEO_TS folder and recompile it into an ISO?
Thanks.

[davexnet]

You can reauthor the whole thing. Use DGIndex to create the d2v index file and extract the audio,
then you can feed these into AVStoDVD along with your new subtitle.

Save as VIDEO_TS OR ISO

[usually_quiet]

IFO files only contain information about the subtitles. The subtitles themselves are stored in VOB files in a subpicture subtitle stream, multiplexed with the DVD's video and audio. So, there is no simple way to substitute a new subtitle for an existing one. You need to re-author the DVD. The method described above is the most straightforward.

Recreating the original menus and structure is sometimes possible but requires additional knowledge and possibly better authoring software that supports more features than AVStoDVD.

[Skiller]

Reauthoring will lose all navigation and menus, unless recreated manually.

Beware, replacing a DVD subtitle is rather complex. I would do it like this (just a rough guideline):

• demux all contents of the titleset in which the subtitles shall be replaced, using PgcDemux
• convert the new subtitles into a suitable binary format (depends on the authoring app)
• author a "dummy" DVD using the demuxed contents of the first step, but with the new subtitle
• replace the corresponding titleset of the original DVD with the prepared titleset of the dummy DVD using VobBlanker

The result would be a perfect 1:1 replacement with no other differences.

[SiS sos]

That kinda sucks (like the authoring software that doesn't cost a fortune), but I'll give it a go. I was really hoping to keep the menu structure, since every DVD authoring program I've used had pretty limited menu creation options. It's so bad that I even tried using an SDK instead! (to no avail)
Anyway, thanks for your replies. I will try out wat you suggested.

[Skiller]

Absolutely all of this can be done with free software. There is no need to tinker with the menus and navigation at all if you operate by replacing titlesets. It would be kept intact.