Audio out of synch

[dea]

Hi!
Didn't know if this thread belongs to the audio forum.
The thing is that the audio out of sync problem only seems to appear after the compilation in maestro (don't know if this all ready accours when I import the assets).

So.. I got theese m2v/mp2 files, that goes out of sync somewhere after compilation. And you all know that you get vob files after comp. so how should I correct this? Since you can't edit audio in vob files.
Wich is the best way to proccess this problem - to "anticipate" the out-of-synch and adjust the audio before I import it to Meastro, or is it better to arrange this actually in maestro?

I have searched the forum briefly without any good results.. but as said - I searched it briefly for the reason that I'm in a little bit of a time pressure. So I'm pleased with any kind of help or suggestions!

Regards
/Andreas


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Edited:
I noticed I went with some strange format for the audio. Of course it should be AC3 or MP3.. I'm testing this now. Probably the problems will be solved. So you don't have to waste your time answering quite yet. Hold your thumbs for me! ;)
Thank you

[dea]

Okey.
So i've got a new problem regarding the AC3 conversion. I've run the mpg file through VirtualDub to get the AC3 file. I've down as the guide here at doom9 suggest and run the .wav file, that VirtualDub creates, through BeSliced to get that AC3 dummy file (wich I select in the dropdown menu). When I import the file to Maestro I get "Media Detection Error". I've also tried to import the original wav file from VirtualDub, with the same results.

After searching the forum for some solutions I've tried to run the file in AC3Fix (the .wav file from VirtualDub that is) and the file that AC3fix creates (I've put .ac3 extension on this one, is that correct?) gives the same error from Maestro at import. I don't get a "file succesfully created" or anything like that from AC3fix, is the file still correct or is it corrupt?

What should I do?

Appreciate any kind of help or suggestion!

/Andreas

[eb]

dea,
I am 99% sure that using ProjectX for demuxing wiil solve all your problems.
You can also make all trim,cut there and as result you will get video,audios and subtitles without any synchronisation problems.

eb

[dea]

Hi eb and thanks for your reply!

I've installed ProjectX and started to demux with it.
Haven't got into the program really (as always in the beginning) so I left the settings as it were when I demuxed my mpg file.

The problem still remains though. The mpv imports just fine in maestro, but the mp2 gets errors. The first one says that it is "unsupported media: invalid sampling rate..." and the other one is the usual "media detection error".
I've tried to run the audio file through BeSliced (Fix file, and then dummy file) and the results are that the first error msg dosen't appear, but the "media detection.." still does.

Any suggestions? Is there any settings I can change in projectx? Further more, how do I get AC3 format from ProjectX? Is the mp2 file some kind of AC3 file?? (I'm still a stranger to this different formats..)

I'm thankfull for further help eb!

/Andreas

[htc10825]

If you got the files thru web or DVB-S/C/T it is possible that they were somewhat crupt(though the mediaplayer can handle them). The easyer solution is to re-encode them once thru besweet. By the way, you can also change the sample rate to 48kHz(if neccessary) or transcode mp2 to ac3.

[dea]

Thank you for your reply!
Okey, so I've runned it thru BeSweet and managed to get a AC3 file, after I've demuxed it with projectx. I can now import the audio file to maestro but I got a real out-of-sync problem with probably a few seconds almost already from the very beginning but it seems to get worse the longer the video plays.
I've read an guide of diffrente sync problems and how to adjust them. But I must say that something weird is that in Maestro the video file has the length of 20:37:07, and the audios length is 18:56:20.
So the audio must play a lot faster (?) then the video file, right?

Don't know how to proceed from here. I truley appricate your help!

/Andreas

[htc10825]

please tell us which file/format/source(from dvd/svcd/i-net/tv-analoge/dvb-s/dvb-t?) and if they syncr in mediaplayer before demux and more important if there is defect in audio&video during the whole playback periode.

[dea]

It's a .mpg file (ye I know....) from internet. The original source is surely tv.
G-spot only gives N/A. And I've tried diffrente files, all though it's a .mpg aswell.
The sync is fine before demux.
Don't know exactly what you mean if there is any defect in A/V during playback periode?

This is how I processed the file/files:
* First I encode them thru TMPGenc, and get a .m1v and a .mp2 file.
* .mp2 thru besweet (after your help) and I get a .ac3 file
* both put together in Maestro, and after compiling a get a massive sync problem

The thing though is that when I first tried it with the mp2 file, I didn't get that much out-of-sync as I get with the .ac3 file.
Hmm.. maybe I should try to run them thru TMPG and get a new .mpg file, and split the new mpg file with besweet (if you can do this?)

Help! :)

/Andreas

[htc10825]

1. If it is a mpeg1 file you can try load it first in VirtualDub, to see if there is something wrong in video(error msg about damaged frame? frame rate ok? etc. in file-info)

2. If all OK then in VD choose audio in full proccessing mode, conversion at 48k-16n-stereo, then "save wave", load the .wav file into a wave editor to check the length of audio, compare the value with that of video displayed in VD.

3. Post the results.

[dea]

1. It seems to be fine if you look in the file info in VD. Didn't exactly know what I was looking for there, so I runned "Scan video stream for errors" and the results were as following:
"0 frames masked (0 frames bad, 0 frames good but undecodable)"
So it seems to be just fine. Heading on to the next step! :)

2. Okey, I did as you said and got the .wav file, loaded it into soundforge and the length seems to be the same length as the video when I load the video in Media Player, 20:40! ye!
But when I later on import the new wave file into Maestro, the length of the audio is as said 00:20:39:13, but the old video file that I've encoded thru BeSweet or TMPGenc is 00:20:37:07..
so when compiled and tested, it's sync in the beginning but in 1 minute or so the video already starts to play faster then the sound.

How should I encode the video to match the audio? Can I do this in VD? Tried to find something, but as I recon, it's mostly used for audio right?
I'm sorry if this/I seems idiotic to you htc, but I haven't had any problems with out-of-sync before.. and I'm so greatful everytime you get me a little bit closer to a succesfull result. Like you did this time!

And oh.. sorry about my bad english, swedish you know ;)

/Andreas

[dea]

Ye!!!!
I de-multiplexed the original file once more in TMPGenc, and out came a fully synced video!!!!

Thank htc for your patient and for your tremendous effort to help!!!!

Now Im happy! :)


Thank you again!

/Andreas

[dea]

Darn... I got stucked again htc :(
As Maestro need to have the files in the same format; PAL/NTSC, I runned the videos thru TMPGenc to get the same format.

But now VirtualDub complains on each of my encoded files that "No video frames found in MPEG file"!!!

Should I process the videos in a diffrente way? Can I change PAL/NTSC on the files without encoding them? Don't I have to encode each video to get the same aspect ratio and so forth aswell?

Help needed...

/Andreas

[Groasnicu']

You can try this guide

http://www.doom9.org/mpg/svcd2dvdr.htm

or this program http://www.svcd2dvdmpg.com/

[htc10825]

you should resample the audio to 48kHz(DVD-Spec), I think the audio in your source is still 44kHz.
Then in your authoring program choose the proper profile(NTSC/PAL) to file your source video(352x240 @ 23.976fps = NTSC, 352x288 @ 25fps = PAL, all other value are invalid). No need to reencode with TMPG, only demux the video to m1v, load the mpg into VDub and make a audio conversion(full proc. 48kHz, 16 bit stereo, save wave), reencode the wave to mp2.

[dea]

Okey. I've sorted everything out now and it seems to be working fine.
I went with Grasnicu' link of the doom9 guide and got the thing up and running.

htc, My files were in fact in 48kHz, don't know why Vdub gave me problems.

I'm encoding the audio files in ac3, since the format will be NTSC (needs to be compatible in US). All files seems to be working with no problem, fully synced and everything. But I have one video that gets a.. what shall I call it.. a "dusty" or "scrapping" sound to it. Think of VHS sound quality in some parts, like the sound is to high and your speaker starts to give a "sparky" sound, and you get the point.
Why is that? The mp2 file works fine, but when encode to AC3, this sound appears. I use AC3Machine like the doom9 guide says. Can you recommend a none-free encoder that is better then the ac3machine. I've read that it gives a huge diffrence?

/Andreas