NTSC, DVDSubEdit, PGCEdit -> a totaly mess?

[Ghitulescu]

I was adding subtitles to an NTSC movie, 29.97fps (not film, 24 or 23.976).
I live in PALland therefore I never experienced this before. Maybe one of you can shed a light in this case.
Practically the SRT was converted via MaestroSBT (29.97 and DF) then remuxed all parts with Muxman.
I would never noticed this issue if one subtitle line hasn't an error that I had to correct. So I checked the result in DVDSubEdit (v1.52) and it didn't show up. The only explanation I could think of is that this particular line overlapped the cell (a CID change occurred very close). And this was my problem.

In the next two snapshots, one can see the two consecutive subtitles, part of the same dialogue, #552 and #553. The first of them, #552, did not appear, it is yet shown in DVDSubEdit. Each photo comprises snapshots from both PGCedit and DVDsubedit, and one sees that even if the LBA numbers look pretty much in order, the timings are not. Please note that the first part is in VCID 2/7 while the second one is in 2/8.



Seeing that PGCedit shows me that VCID 2/7 should end at 0:28:45 and 2/8 at 0:35:55, both dialogues must have been in VCID 2/8. So I went further. I looked at the last subtitle line.



DVDsubedit shows it at 2:18:22, but PGCedit insists that the movie ends some 7 minutes earlier, at 2:11:57.
As a last resort I checked the SRT from which the subtitles originated.



The strange thing is that the subtitles are in synch when played in DVDsubedit. They are also in synch when played back VOB by VOB in VLC and other likewise software players. I haven't tried it on a standalone.

Any thoughts on how to make #552 appear? Or why this behaviour?

[TheSkiller]

Originally Posted by Ghitulescu

Practically the SRT was converted via MaestroSBT (29.97 and DF) then remuxed all parts with Muxman.

As far as I know, 29.97 drop frame means the generated timecodes will be the same as if the frame rate was exactly 30 (30/1) not 29.97 (30000/1001), and to keep synch a (virtual) frame is dropped every 1000 frames.
I would try to generate the timecodes in real non-drop-frame 29.97 format since this is what the video usues as well.

Sure, this shouldn't lead to a difference as big as 7 minutes but it's worth a try. Maybe there's some odd conversion going on between the original timecodes in your SRT and what MaestroSBT spits out.

[Ghitulescu]

The difference cannot be accounted for, no matter what conversion would have been used (24->23.976, 24->25, 24->29.97, 24->30, 25->29.97, 25->30, 29.97->30 and vice-versa).

[Ghitulescu]

I discovered the issue.

DVDSubEdit works on VOBs not on PGCs.
It probably adds the time of all cells included in the VOB.

On my DVD, there has been a cell (VCID 1/1), hidden in that VOB, that contained some studio logos, said cell accounted for the extra duration (some 6:31). The timing was shifted with its duration, thus the subtitles stayed in synch, yet they have been shown a wrong time in DVDSubEdit.

I am not sure whether this is a feature or a bug.