Fixing an out of synch dvd

[bidelman]

This is the second of my synch questions, and should bring me up to speed , knowledge wise. Hopefully there is a solution that does not require rocket science.

I have a dvd that was was mastered from a vhs source. So I can't assume anything about how it existed in original form. All I know is that the sound and audio are off base, and spot checking through the disc, it never seems to catch up.
I have seen those that do "correct".

I read through audio and restoration, and all but became frustrated at what I read.

Its not something of consequence, so if its time consuming, and moreover really expensive because of necessary software, I won't bother.

Thanks,
Steve

[manono]

Its not something of consequence, so if its time consuming, and moreover really expensive because of necessary software, I won't bother.

It'll take some time, but in principle it's easy and won't cost you a dime.

1. Demux the video (PGCDemux).
2. If the delay is small (300ms or less), remux immediately, setting a delay in the audio (Muxman).
3. Add the remuxed video DVD back into the original using the 'Replace' button of VobBlanker. Open the original in VobBlanker, highlight the video so it appears in the lower screen, highlight it in the lower screen, hit ' Replace', scroll to the remuxed DVD, give it an output folder and 'Process'. That way you get back your menus and anything else that DVD might contain. If no menus, you're done after step 2.

If the delay is greater than 300ms get rid of it entirely before remuxing. What you use depends on the kind of audio. If AC3, DelayCut. If PCM WAV, a WAV editor such as the good and free Audacity.

[bidelman]

I am printing out the instructions as I type this reply.
Nothing ventured...nothing gained.

I do appreciate it.

steve

[jman98]

Be warned that fixing this kind of problem is highly labor intensive as you basically have to guess how far off the audio is, remux and generate a completely new DVD and then play that prior to burning to check to see if you guessed right. If you didn't, then you have to make the delay larger or smaller as necessary and try again.

I don't suppose there is any chance you can contact whoever you got this from and ask them how it was created. If you downloaded this off the internet, never mind. If you got it from a real person they might possibly want to know that the audio isn't in sync.

[manono]

Be warned that fixing this kind of problem is highly labor intensive as you basically have to guess how far off the audio is...

That's not exactly true. You can get the delay pretty accurately the first time - as accurately as your ears will allow anyway - by playing a VOB using Media Player Classic Home Cinema (as well as other players and programs) and using the +/- keys to adjust the delay on the fly. The delay that puts it back into synch is the delay you set for the audio when remuxing.

[bidelman]

All is sounding good,

Continued Thanks,
steve

[gilligan103fan]

As a rough guide, about 180 milliseconds seems to be the smallest time interval that a viewer will perceive as being "different". So as a first attempt, you could try adjusting the audio by multiples of 180ms to get the audio approximately in sync.

If you ever acquire TMPGENC XPRESS to fix up other video problems, it's worthwhile to know that it also has an audio gap feature for advancing/delaying the audio in relation to the video. It's a lot easier to use than freeware tools.

[dphirschler]

@manono, very good guide. I was not aware that I could do that without reauthoring and rebuilding my menus.


Darryl