Audio sync ahead and video freezes

[lingoguysw5]

Hi I have this great pic except the audio moves ahead during the film. I understand that tmpgenc can rectify this by increasing/decreasing the audio gap but if you can't hear with tmpgenc how can this be achieved?
Secondly I checked for video bad frames using Virtualdub and the result showed "no bad frames found" However this is not not the case since it freezes from time to time which no doubt doesn't help the audio sequence. What can be done to overcome these problems. All suggestions welcome. Thanks alot Clive

[setarip]

"I understand that tmpgenc can rectify this by increasing/decreasing the audio gap but if you can't hear with tmpgenc how can this be achieved?"


PLAY the file - watch and listen - estimate the delay.
Then use trial and error to adjust...

[lingoguysw5]

Where is the tmpgenc preview volume?

1.Where is the volume on tmpgenc so I can check the audio/video synchronisation?

2.Is the audio gap method in tmpgenc also used to prevent the audio speeding up half way through the film?

[setarip]

For goodness' sake, there is no audio output in TMPGenc. Play the file either in Windows Media Player or under a software DVD player, such as WinDVD...

[lingoguysw5]

Well thanks for your warm-hearted reply setrip, however, to adjust the audio using an outside method seems to me to be a pretty long-winded way of getting it right.
Why? Because: (Time consuming) It could take for ever!
I take it one needs to count the seconds or maybe m-seconds =+/- for that much, followed by encoding a portion to verify the hopefully correct adjustment. Surely there must be another way of adjusting this besides using TMPgenc. Incidently, I extracted the audio from the video believing it to be the better option. Would this also be the case?

[setarip]

You know, Clive, you speak of using TMPGEnc to adjust the audio/video synchronization - so I've thusfar presumed you're dealing with an MPEG format file. But I just noticed that you also refer to having used VirtualDub to check for bad frames, so I'm now wondering if, perhaps, you're dealing with an .AVI file (DivX-compressed or otherwise).

Exactly what is the format of the file that's out of synchronization?

[WildmanJoe]

Use this player called MV2 Player to offset the audio by X seconds and see if the video and audio are in sync.

http://mv2.czweb.org/

After that, use either VirtualDub or TMPGEnc to offset the audio correctly.

[lingoguysw5]

The format is divx which I first use with Virtualdub to render as an avi file for the video and mpg for the audio. I then use TMPGenc just to encode and perhaps clip margins.

I have downloaded WildmanJoe's website and give it a go to see if that resolves the problem.

[setarip]

"The format is divx which I first use with Virtualdub to render as an avi file for the video and mpg for the audio."

1) I'm guessing tha the audio is actually .MP3 not "mpg"

2) If the DivX-compressed .AVI is out of synch and

A) If the difference between audio and video is constant throughout the video:

Load the file into VirtualDub, VirtualDubMod, or NanDub.
Set BOTH "Video"(VirtualDub, VirtualDubMod and NanDub) and "Audio" (VirtualDub and NanDub - VirtualDubMOD>"Streams>"Stream list") to "Direct Stream Copy".
From the "Audio" dropdown menu, select "Interleaving" (For VirtualDubMOD, rightclick on the listed audiostream and then select "Interleaving")
Under "Audio skew correction", set an appropriate number of milleseconds (positive or negative) in the box labelled "Delay audio track by"
Save with a new filename

B) If the difference increases as the movie plays:

From under the "Video" dropdown menu, select framerate - and select "Change so video and audio durations match"

[lingoguysw5]

You guessed right. I use mp3 to compress the audio.
Am I to understand if I adjust the audio gap with Virtualdub, I'll be able to check it's correctly synch before encoding?

Should it pose a problem if I use Direct Stream Copy for video and then Full Processing for of course the mp3 audio?

Sorry to be a pain setrip. Will these new instructions which I understand perfectly, also enable me to get rid of the freezes which appear in the movie that I would have ran for "no bad frames found"? Looking forward to your warm reply. Clive

[setarip]

"Should it pose a problem if I use Direct Stream Copy for video and then Full Processing for of course the mp3 audio?"

Since your .AVI already contains an .MP3 audiostream, there is no reason, need, purpose, or benefit in setting "Audio" to "Full Processing Mode"...

[lingoguysw5]

Oh really! I'll give it a go then next time and just do direct stream mp3

How do I solve the bad frames issue? If I have run Virtualdub's "Check for freezes" and the result is "no bad frames found" but it still freezes, what could that be attributed to? Any ideas? Thanks for your patience, anyway.

[lingoguysw5]

I am still having trouble setting the audio using Virtualdub. How do you set the positive and negative values is it with a +/- or somethng i.e. 7000+ for positive or 7000- for negative?

Is there any need to touch upon Preload 500 ms of audio before ms starts? Or Interleave audio every 1 frame ms?
Plse let me know.

[setarip]

"How do you set the positive and negative values is it with a +/- or somethng i.e. 7000+ for positive or 7000- for negative?"

Positive values are entered without any sign. Negative values are preceded by "-" (e.g. -7000)

"Is there any need to touch upon Preload 500 ms of audio before ms starts? Or Interleave audio every 1 frame ms?"

No - If there were such needs I would have stated so...

(Stop trying so hard to make things more complex than they really are)

[lingoguysw5]

After a short duration the audio moves out of sequence.


I have matched the audio to video using Virtualdub Original & viewed with WMP/Divx/Virtualdub playbacks. However, this is only working for a very short duration then it gradually moves out of synch. As per your previous instruction. I then proceeded to: "Change so video and audio duration match" but this has not made the least bit of difference. It still moves out I want to get it right before I encode my avi file with TMPgenc. Incidently in case you ask I am saving using Virualdub the whole file using Start/End offset - Direct streams Video and Audio Enable interleaving remains unchecked. I hope that helps

Any positive solution that can be offered will be greatly appreciated. I do hope that I am not making things more complex than they really are Thanks again for all your help thus far Clive