How to set a delay on subtitles without remuxing?

[Denis Fomin]

I have a DVD on which subtitles appear 1 second too early. I would like to "time-shift" them. I know audiostreams in VOBs have an optional delay but what about subtitles streams? Do they have a delay? And if so is it possible to change it with remuxing/reauthoring? Maybe somewhere in IFO... :)

Thanks in advance for your help.

[jsoto]

AFAIK, you have to reauthor. There is no delay info in IFOs

But I'm wondering what will happen if a "simple tool" change the PTSs in the sub (or audio) packs... A small change may be work.



jsoto

[mpucoder]

@jsoto - You can't change the PTS by very much without having to move the data itself. You could probably change it by a frame or two (frame = 3003 NTSC or 3600 PAL)so long as (PTS-SCR > frame_duration.
A whole second is a huge change, requiring the data to move a couple VOBUs.

Audio is even more critical, since the decoder has only a 4K buffer and audio frame durations are 2880 for AC3, 960 for DTS.

@denis - the audio delay is used by the multiplexer to determine the timing values. It is not retained anywhere or changeable without a remux.

[jsoto]

A whole second is a huge change, requiring the data to move a couple VOBUs. I know, I was thinking in one frame or two (40/80 msec).

BTW, a NTSC frame is always 3003 clock tics?. (I'm using 3000 in Vobblanker, but seems it is wrong).

jsoto

[mpucoder]

Originally posted by jsoto
BTW, a NTSC frame is always 3003 clock tics?. (I'm using 3000 in Vobblanker, but seems it is wrong).

jsoto

Always.
The "gotcha" with NTSC, though, is RFF (adds one field, or half a frame). And it turns out that cell elapsed time uses non-drop counting.

[Denis Fomin]

Thanks for the replies. So it seems that remuxing/reauthoring is inevitable. Naturally the following question arises :) what is the easiest way to do that? Bearing in mind that I would like to keep the menu and the extras and just time-shift subtitles (in 3 languages) in one VTS.

[jsoto]

@mpucoder,
Thanks for your clarifications, always clear.

@Denis Fomin
Well, I never tried, but I can give you some indications:
A) Demux the PGC in its elementary streams. You can use PgcDemux (see my signature). You will also get a log file with the audio delays and a Celltimes.txt file
B) Shift your subs. May be DVDSupTools (http://web.quick.cz/FKasparek/Software/DVD/DVDSupTools.htm) can do the job.
C) Remux again your PGC using IFOEdit (if PAL) or ReJig (if NTSC). Up to now IFOEdit authoring has some issues in NTSC. You will need the audio delays and the Celltimes.txt obtained in step A.
D) Replace the original PGC with the new one using VobBlanker.

Good luck.

EDIT
You have to follow this procedure in each PGC you want to shift. (May be your VTS has more than one)
/EDIT

jsoto

[CoNS]

Yep, jsoto is right, that is the way to do it. I've added quite a lot of custom made subtitles the very same way.

For step B I recommend Subtitle Workshop. You can easily add or subtract a time delay using this tool.

Jsoto, do the tools you suggested have a GUI? The subtitle decoder tool sounds really cool. I wonder if it uses OCR like Subrip?

[jsoto]

Jsoto, do the tools you suggested have a GUI? The subtitle decoder tool sounds really cool. I wonder if it uses OCR like Subrip? Frankly, I do not know.
jsoto

[Denis Fomin]

Thanks for the directions. Please look at some question below.

@CoNS
According to the descriptions the decoder function of the DVD Subtitle Tools results in something like

{frame_from}{frame_to}{VTS_01_0.20_000001.bmp}

that is OCR is not necessary because only the <from> and <to> fields are being parsed but the subtitle text left in bitmap form.

As for the my problem. I read a couple more sources and the general idea seems to be the same:
1) Demultiplex video/audio/subtitles.
2) Manipulate subtitles.
3) Multiplex video/audio/subtitles back together.
4) Replace old VOBs by the ones created in step 3)

Here's some questions/problems I have. Hope you could help me:

(a) The approach you (i.e. jsoto :) ) suggested works on per PGC basis while other sources suggest methods on per VTS basis. I assume you are trying to take care of the cases with multiple PGC for instance one for theatrical cut and one for director's cut, is that correct?

(b) Kind of connected to the question (a): in my case I have only 1 PGC in my VTS so is there any difference between using PgcDemux and VobEdit for demuxing to video/audio/subtitles?

(c) My VTS is NTSC and I tried to use ReJig (0.5d and 0.5e) to mux video/audio/subtitles back together but all I get is some small ~50KB file for VTS_01_1.VOB instead of 4+ VOB files 4GB total size. Is there any solution for that? I tried IfoEdit for curiosity sake and it did mux everything but palyback (in IfoEdit itself) is jerky and total runtime is different, so as you said I can't use it to mux NTSC. Are there any other tools that can mux video(NTSC)/audio(AC3/DTS)/subtitles(SUP)?

(d) Regarding "Replace the original PGC with the new one using VobBlanker." could you please elaborate on that? That is how exactly do I do that?

(e) I tried using VobBlanker before, BTW very nice tool, thank you for it :) , but Nero didn't like its output. Said that one of the files size wasn't in 2K multiples. I checked and the only one that could be it was VIDEO_TS.VOB that had 0 bytes size. I tried to burn anyway but my standalone player (Toshiba SD-2109) could not read it. So I guess Nero was right. So the question is: what might be the cause for that (that is VIDEO_TS.VOB being of zero size) and how can I avoid it in the future?

Thank you for your help.

[jsoto]

(a) No, but a multiple PGC can have different streams/delays in each PGC. So definitively you have to process each PGC in a different way.
(b) I'm sure demuxing with VOBEdit fails in a multiPGC VTS. But, it can also fail in a single PGC one, thought. IIRC, VobEdit resets timestamp counter if the VOBID changes. (assuming one VOBid per PGC, which is not always true).
(c) In its first step, ReJig multiplexes all in one file, so probably you need an NTFS file system, do you have it?. But, fortunately, seems IFOEdit 0.97 has fixed NTSC authoring problems
(d) It is in the help file. Just open your VIDEO_TS.IFO, select your VTS in TitleSet list, select your PGC in PGC list, click "Replace" button and select your VTS_01_1.VOB newly authored file. Finally select the output folder and click process.
(e) Menus with 0 bytes size: Delete the 0 byte files, open VIDEO_TS.IFO in IFOEdit, do "Get VTS sectors" and you have it. There are some discussions here about Nero and it's 0 byte files complain.

jsoto

[Denis Fomin]

Thanks for your very clear answers :) I'll experiment.
As for ReJig. I do have NTSC filesystem. During the authoring I can see the temp file ReJig creates (mux.vob I think) and it reaches about 4.2 GB in size and then oops, it disappears and instead I have 50KB VTS_01_1.VOB :( and appropriate IFO files

[Denis Fomin]

Unfortunately I couldn't find where I can download IfoEdit 0.97 Is it available to the general public already? If so could you please post a link to where it may be downloaded from. Thanks in advance :)

[jsoto]

There is a thread of ifoedit 0.97. I don't have any problem downloading from here:
http://www.ifoedit.com

jsoto

[Denis Fomin]

Well I guess it's my luck :( By "thread" I suppose you mean a thread in the forum out there. But when I click on "Forum" button I get

"This area is for contributors only"

What can be wrong?

[movie_subtitle]

@Denis, you could use an online time-shifting tool on http://subtitle.ss-birthdayreminder.com ... it takes a couple of seconds to upload the subtitles, tell how much you want to `shift` them and you're ready to download the new version of subtitles ... it can shift *.sub and *.srt files
have fun

[blutach]

You revive a 4 year old thread for this? Plus according to the site, the subbies are limited to 200kb. Use DVDSubEdit instead.

Also, I have eliminated the SPAM from your signature. Please read our rules concerning spam.

Regards