Audio going progressively out of sinc!!!!!

[neo2810]

Please could someone help me on this one???
I have a couple of movies in AVI format which are perfect when played. They are running at 23.97fps. When I convert them to MPEG, I change all the setting to make it VCD/PAL compliant (25fps 352x288, 41800MHz 224bit audio). The problem is that the audio seems to run fractionally slower than the vidoe so that it's ok at the start, but about a second out by the end of the film. I've tried many options, but nothing seems to work.... Anyone come across this, or better still, find a solution???
Thanks guys...

[Borgster]

Your sinc problems is created bij the change
in framerate from 23.96 to 25.00
You'll see that the length of video(movie)has changed

Why don't you leave it at 23.97 most DVD(also stand-alone)players play NTSC on your PAL TV system.

I've tried to convert Divx NTSC(and NTSC film) to PAL and as far as I know it's not possible. Using NTSC input in TMPGEncoder and using PAL.mcf creates a stop in video every second or so (very irritating!)

So, if anybody else knows how to do this please help!

[neo2810]

Thanks for the reply Borgster. Keeping the file as NTSC is something I'm trying to avoid cause some (very few, but still some) DVD's have trouble with NTSC. I'll try that nonetheless, and see if we can get it working...
Does anyone else have a solution for converting NTSC (23.97fps) to PAL (25fps) without cracking audio out of sinc?

[ngnr]

I came across this same problem and while theoretically, I figured I should be able to fix it by shortening the entire audio track by compressing the time using an audio editor, I was not able to make it work in practice. I eventually gave it up as it was a colossal waste of time. Good luck if you decide to go that route but it can be a time consuming process if it doesn't work the first time and you are stubborn like me.

[porto]

I had exactly the same problem and found a 1:1 work-a-round (by my knowledge only works with movies in 23.976 ntsc format):

load the WHOLE .avi (divx!) into TMPGenc and encode the thing to mpeg with the pal parameters. As you can see the lipsync is still present in the mpeg file after encoding. Now split the mpeg with e.g. VCDcutter or another splitter which can handle .mpg files... the two streams are still in sync.
now burn the damn things to vcd... play it and see... still synced!

NEVER convert the divx audio to wav and load the things in Premiere, it will be ALWAYS progressively out of sync!!!

sometimes I had this problem that I encoded an DivX to mpeg but after a few mins the sound disappeared.. quiete strange, not? In this case download VirtualDub, set the video to direct stream copy, the audio to full processing mode and save the thing as an .AVI file.... (it will make a 1.5Gb file of a circa 2 hour movie).... now, the resulting file can be encoded to mpeg with sound and so on....

[neo2810]

Guys, thanks for all the suggestions.
Shrinking the audio may be an option, but the chances of shrinking it to the correct size are minimal, and could take multiple attempts...too time consuming!
Porto, your suggetion of loading the WHOLE AVI file into TMPGEnc is exactly the way I normally do it. I only took the audio off when the sync problem started. It's only happened on a few files, and I think it's only those which are 23.97fps which I'm trying to convert to 25fps. Saying that, I HAVE managed a 23.97fps to 25fps conversion where the audio has remained in sync, so I don't know if it has something to do with the original audio settings or what?
Anyway, I'm going to try using VirtualDub to sort the problem.
Another suggestion was to convert the file as NTSC and burn it as such. I found to my dismay, that the audio was still out of sync after converting to MPG (NTSC), even thought the AVI file was perfect.
I'm stumped....Somebody PLEASE come up with a solution?

[KuskenLars]

hm... can't really remember this but, there are some settings in the environmental tab that you can raise the priority, could help...
(Sorry I can't remember the whole thing...)

[porto]

neo2810,

I have the out-of-sync problem too with only a few files but only with the ones which are encoded with 24 fps... fortunately only 1 of the 20 movies is encoded that way
I thus have no probs with 23.976 movies, weird you do.

[miko]

Creating a PAL (S)VDC from a NTSC source in e.g. TMpgEnc will always produce a jerky movie. Shure the sound is synched but TMpgEnc will just add extra frames wich are duplicates (thus the jerkiness when the "same" frame is played more than once).
The only way to convert NTSC to PAL is to extract the audio and shrink it. The biggest problem is the extraction/convertion from Mp3 to wav. I've tried several programs like VirtualDub and lame to do this and simetimes it seems impossible to get all the information (the extracted wav is to short). But if you get the whole track all you have to do is shrink it in a sound editing program. That bit is always easy. Check the length in the converted avi (25 fps) in Vdub...

/Miko

[Borgster]

Neo2810,

If your going to keep the format NTSC, look in virtualdub,
(or file properties in windows explorer)if the audio stream
is 44100 Hz, if not Set video to direct stream copy and audio > conversion select 44100 and NO compression. In this way the audio stays in sinc after conversion to MPEG.
If you use a seperate audio file (same settings, then save WAVE) the covnversion to MPEG goes (a little) faster.

Good luck

[neo2810]

Thanks for the latest ideas guys....

I'm especially interested in the shrinking of the audio idea. I have never had a problem extracting ALL the audio from a file, just didn't know correct way to shrink it to correct size. Thanks to Miko, I have a good idea on how to do this...
Just seen Borgster's last post... I'll try that this afternoon... thanks. Sounds promising.. Fingers crossed I can get it right this time....
Will post tomorrow and let you know of my findings, cause I think this is a fairly common problem with those new to converting/ burning movies. This will hopefully help others....
Nice one!

[Borgster]

Read somewhere that audio schrinking can be
done with Cool edit. going to try
that one later this day..

CYA

[neo2810]

Thought I'd add this because it sounds plausable. Not tried it yet, but will tonight.
This I found on another thread....

"There IS a way to convert NTSC Film to PAL with no flaws. I live in europe too and used to do this with DivXs I would get from the net and turn them into PAL SVCDs. Works great. It's been some time since I last did it, but here's basically how I did it:

To turn 23.976 FPS or 24 FPS into 25 FPS you need to SPEED UP the movie. This is always what happens when playing back 24 FPS movies in PAL system, thus European DVDs always have like 5 mins less in each 2 hours of film.

To do this, I frameserve the film in VirtualDub, changing the FPS to 25. Of course, you might be thinking, this gets the audio out of sync. Well, you need to speed up the audio too. So demultiplex the MPG or use virtualdub to save the AVI audio in a WAV file (this before changing to 25 FPS...).
You'll have to open the audio file in such a program like sound forge, or another that lets you change the sampling rate WITHOUT resampling the audio (sound forge has an option for this called 'Aply sampling rate only' or something). You have to do some calculations to figure out the new sampling rate. Here's some examples:

Basically, use the formula

New_SamplingRate = (New_FPS * Old_SamplingRate) / Old_FPS

48,000 Hz at 23.976 FPS
(25 * 48000) / 23.976 = 50050, so Use 50,050 Hz

44,400 Hz at 24 FPS
(25 * 44400) / 23.976 = 46250, so Use 46,250 Hz

And so forth...

Now save this new audio file, and encode the frameserved video at 25 fps with the new audio file (you'll have to change the sampling rate back to 44,400 in the MPEG encoder).

Well, that's about it. Hope *someone* is able to undestand this"

Hope this helps....

[mikk]

Professional dvds are sped up.

This is why the PAL system is better than the NTSC system for film sources (almost all movies).

PAL is 720x576 25fps, NTSC is 720x480 30fps

Some people say 30fps is better, but: Films are made in 24fps, so when a film is played on NTSC, every 2 frames a frame is repeated, then every 3 frames a fram is repeated, 2,3,2,3 etc... so u aren't getting any more frames.

With PAL u get 20% more resolution and an unnoticable speed up by 4%.

[neo2810]

That's useful info Mikk. Thanks...
I do know the logistics behind the difference between PAL and NTSC, but we are trying to find the best way to convert NTSC to PAL for European users, without shunting the audio out of sycn. My last post seems like a plausable way, but I haven't had time to try it yet... will tonight.

I believe we are getting closer tho..