subtitles 25fps, video 24fps both synchronized - converting to DVD, a mess

[Ze Tomes]

Greetings,

Synopsis: The original sources, video and subtitles, (functioning and synchronized) are at diferent formats respectively, NTSC (23.976) and PAL (25). Strangely they function this way. My probem resides in converting them to DVD preserving the original sync. They were both extracted from a matroska file.


original file: mkv (NTSC, 23.976 fps)
extraction of subtitles: mkvestractgui
extraction of video: mkvmergegui

after extraction:

video.mkv (NTSC, 23,976 fps)
subtitles.srt (PAL 25 fps)

Although in diferent formats both video and subtitles only function this way. Don't know if it's an error of mine while extracting or if it's orginally this way. Anyway my problem starts here.

Using AVStoDVD I tried to make a good conversion of both to DVD but:

1st attempt - using the conversion to PAL with "Use PAL SpeedUp for NTSC-film to PAL"
resulted in desynchronization, because the video was converted but the subtitles kept the same.

2nd attemp - using convertion to NTSC resulted in desynchronization also, because the video chenaged to 29fps and the subtitles were in 25fps.

then I created this file for testing:

1(+)- converting the video to a muxed mpeg2 in PAL format

from 1, I tried to synchronize the subtitles and the video with Subtitle Edit, but even synchronizing the start and end points the result sooner or later was desynchronization. My intention was to put them both in PAL in AVStoDVD avoiding further conversions.

I was hoping to regist the start and end points so I could convertet the subtitles matching the video. I thought only in two options:

A - subtitles and video in PAL but previously synchronized before convertion to DVD
B - subtitles in PAL (originally) and video in NTSC (originally) - they must be desynchronized before conversion*.

even in diferent formats originally (or my mistake in extratcion) they were perfectly synchronized. So I had to change the subtitle format to NTSC, record the values of synchronization points, and then change them again to PAL with that recorded values, *so after the coonvertion to DVD Pal (only affecting the video) both would converge to PAL (subtitles kept the same)

From A, I had the same problem as in 1(+), I wasn't able to synchronize the subtitles. Probably my mistake

From B, everything was looking perfect, but graduallythe synchronization was getting faded. I was expecting this to result with test 1(+).

So, I'm quite stucked in a alley... and each experience takes me one day, and I'm already getting confused if the experiences were properly made as I exposed.

Either way or another, I would like to know if I had the solution amidst those experiences and by some mistake something failed, or, which is the better and the simplest solution for these odd inverted synchronized formats. I think (B) might be the solution but I need confimartion because probably I'm making some confusion about it (most probably because I only realize much later I was dealing with 2 kinds of NTSC - 29 and 23, 976 fps).

Thanks in advance

[MilesAhead]

You might experiment with this:

http://www.autohotkey.com/forum/topic41466.html

The other method you might try is using an AviSynth script.
First see this guide to using FitCD:


Set the DVD output side so that PAL is not checked.
Set it to 16x9 Anamorphic.
Load the .mkv file into FitCD.
(Even though it pops up an error it will still do
the calculations needed and produce the script.)

You'll get something like this:

DirectShowSource("movie.mkv")
BilinearResize(656,448,0,1,1920,1078)
AddBorders(32,16,32,16)

Copy the script to AvsPmod. I recommend AvsPmod because it has
a preview function that will show how the subs will look and the resizing.
If people look like pencils or are too fat the aspect ration is messed up
and you can see it right away.

Note that the numbers will be different depending on
the resolution of the video. But FitCD figures out how
to fit it into a shape that can be resized to anamorphic
16x9 without getting people with fat heads.

At the top add this line:
LoadPlugin("C:\Program Files\AVStoDVD\VobSub\VSFilter.dll")

change the DirectShowSource line to this:
DirectShowSource("movie.mkv",audio=false)
(Of course using the name of your .mkv file.
Also to process .mkv with DirectShow you may
need to have Haali Media Splitter installed.)

Now you want to add in your srt subs
TextSub("movie.srt")

When done you should have a script something like this

LoadPlugin("C:\Program Files\AVStoDVD\VobSub\VSFilter.dll")
DirectShowSource("movie.mkv",audio=false)
BilinearResize(656,448,0,1,1920,1078)
AddBorders(32,16,32,16)
TextSub("movie.srt")

You feed this to an encoder that will output an .m2v DVD video file.
It will have the subs burned in. If the subs are in sync, then you
run the .m2v file through DGPulldown with the default settings.
This will set it to play at standard NTSC frame rate without changing
the frame rate.

From this point you extract the audio from the original .mkv
(MkvExtractGui-2 is what I use.) then use an authoring program
such as DvdAuthorGui to put the audio and video together as a
DVD with burned in subs.

It's not as hard as it sounds.

If the video audio and subs were all in synch in the .mkv then this
should work as I've done it a bunch of times. Take a look at a program
that can convert just the video portion such as QuEnc. If you have
AVStoDVD then one of the subfolders has QuEnc already. It's easy to
use by itself. You feed it the AviSynth script. That's the file made above
with DirectShowSource.. just save it with an .avs file extension.

If you get this to work you might find it's a neat quick way to get
great quality DVD9 output from .mkv input. Any movie 2 hours or
less you should be able to set QuEnc to 8500 kbit CBR one pass mode.

Just look online for guides for the tools mentioned.

[johns0]

Srt subtitles are not based on pal or ntsc but on timecodes in the file,they can be converted to play on pal or ntsc by changing the timecodes with an editor such as subtitle edit,you're either doing something wrong with the extraction method or the subtitle is wrong to begin with.

Try mkvcleaver to extract with instead.

[MilesAhead]

I've not had a problem extracting with MkvExtractGui-2. Usually I extract the subs and run the process I described. If the video conversion is successful, with or without burned subs, then I extract the audio and author. MkvExtractGui-2 can also successfully extract PGS subs. It's been working for me right along.

One of the reasons I suggested the burn in method was so the OP could check things out in AvsPmod preview. It will show the subs as well as aspect ratio before going through all the processing.

But there's usually 1/2 dozen ways to skin the cat.

[Cornucopia]

2 kinds of files: 1 video, 1 text. The video you will have to convert from MKV to MPG2, but you don't want to do much else or you'll further degrade the quality. You don't really get "quality degradation" of text files (BMPs of text, yes, but Text, NO). So the one you want to do any "conversion" on is the text file.

I'm with johns0, modify the timecodes. You don't have to do much - HH:MM:SS should be the same, just FF that should change (though you might have a DF/NDF difference). I've done a similar thing in the past using a couple of scripted Excel functions.

Scott

[Ze Tomes]

Thank you all for the answers!

Before I desperately posted this thread, I resolved to use my last shot on my own experience. I reset and started the process from the begining, only that at this time I kept the matroska video format only extracting the subtitles later converting them to srt.

For my surprise, I discovered that the framerate of the srt file changed if having the same name as the video when using subtitle edit. When alone or with a diferent name its basis was 25 fps, when changed to the same directory of the video or renamed equally to the video's name it changed to 23,976 fps. It was something I was missing and intringuing to notice this behaviour. Somehow (techincal matters: major zero) the matroska file influences the subtitles file if with the same name, or it's the subtitle edit who's responsible for that... Dunno

In my previous tested theory with another video, for the subtitles being synchronized after the conversion to PAL (Use PAL SpeedUp for NTSC-film to PAL) they had to be previously in PAL and converted for not synchronizing with the video. I've tested that with originally both video and subtitles in NTSC format. I just had to adjust the subtitles to PAL and keep the NTSC video format for direct conversion to a DVD Pal (Use PAL SpeedUp for NTSC-film to PAL)

In this case it was cracking my head.

I isolated the subtitles (25fps) changed its frame rate to 23,976 and observed after if their frame rate would change in the presence of the video file as I was expecting they wouldn't. It didn't happen, they kept adjusted to the video format, althought the timelines were of the previous changing, both video and subtitles were perfectly matching.

Keeping both in the same directory with the same name, i re-synchrnized the subtitles framerate to 25fps again. I was expecting desynchronization, exactly what it happened, my purpose ad the possibility for a good convertion. I wasn't hoping too much of this but in the light of using the original matroska and the knowledge of changing framerates in the presence of the video file it was worth a final try.

The rest of the process was equal to the previous experience. Video in NTSC (23,976), subtitles PAL (25) (both desynchronized) converting to DVD PAL.

Just when I was seeing if the thread had any responses the process of convertion concluded, and the result was a big smile on my face. It did perfectlly. I wasn't having this amount of work - 7 experiences x 3+ hours each - if I didn't like so much this movie (sorry, have to say it - Twilight Samurai)

I'm a total nerd in this editing thing, and I was gathering strenghts taking a deep breath to follow your advices before the surprsingly positive conclusion of the convertion, because it's to much for my greenish knowledge of this matters and a single step is a tinny baby step.

Although I don't quite know how did it function technically, I was following the experimental way.

Thank you very much for your attention

[MilesAhead]

I"m lost. Did you get it to work or not?

[MilesAhead]

2 kinds of files: 1 video, 1 text. The video you will have to convert from MKV to MPG2, but you don't want to do much else or you'll further degrade the quality. You don't really get "quality degradation" of text files (BMPs of text, yes, but Text, NO). So the one you want to do any "conversion" on is the text file.

I'm with johns0, modify the timecodes. You don't have to do much - HH:MM:SS should be the same, just FF that should change (though you might have a DF/NDF difference). I've done a similar thing in the past using a couple of scripted Excel functions.

Scott

Depends what you will play it on. At least in my case Gen1 WD set top box easily goes out of sync with external .srt subs. The burned in subs look better and don't get "lost" if I FF or restart the film. Plus burned in works on everything since it's part of the video. If I don't have to encode then for my set top box I often convert .srt to idx/sub using AviAddXSubs. Also WD Gen1 has crummy options when it comes to external .srt. At the largest font and thickest border settings, they are still hard to read. With AviAddXSubs I can adjust all that and choose my font and border thickness.

People seeing degradation of video must have 5' wall mounted HDTV. I don't see any on my Sony Wega HDTV.

[Ze Tomes]

I"m lost. Did you get it to work or not?

Perfectly, fluid, synchronized! Much more simplest than I thought.

In all those experiences, I concluded that I just had to change the subtitle name to match the video's name, and the subtitle's framerate to 25 (subtitle edit), while staying both at the same folder. In the "presence" of the video the subtitles fps changed to NTSC (23,976) automatically although continuing synchronized, so the changing rate had to be made when both files were at the same directory, otherwize independently, the subtitles wouldn't change because originally they were already configured to 25 fps. The result to be expected to function in the conversion to DVD PAL had to be desynchronization between video and subtitles. I don't know if using the original mkv file instead of the muxed mkv (without subtitles included) made any diference in the process. I think not, but the notion of the frame rate behaviour amidst video and subtitle being together indeed yes, made a total diference.

subtitles (25)
video (23,976)

both desynchronized as pretended ready to go for convertion to PAL on AVStoDVD (Use PAL SpeedUp for NTSC-film to PAL). After conversion the video frame rate would match the subtitles'.

Clean result.

[MilesAhead]

Right. I gotcha'. A lot of programs will check for ancillary files of the same base name when dealing with video subs audio etc. and take info from them or load them automatically.

[Ze Tomes]

Got a formula that's been functioning since!

uee....!

Thank you again!