video & audio sync question

[martino]

I wasn't sure where to stick this, so here it goes;

I have an MKV file, with H264 video and Vorbis audio. How could I find out whether they are in synch or not?


Thanks!

[setarip_old]

Hi!How could I find out whether they are in synch or not?Can't you just play it?

[martino]

Yeah, I can...but it's really hard to find out whether I should delay the audio track by +42ms, -42ms or none at all. :)

[setarip_old]

If it's "really hard" to notice any out-of-synch behavior, then there's no delay necessary...

[mitsubishi]

You could contact the university responsible for the 'Automated Lip Reading' technology that was used on the Hitler tapes this week and match that with voice recognition software, but that of course isn't going to happen :p

Wouldn't you have to only move back about 14 metres from the screen and speakers to knock it out by 42ms anyway? Unless my headcalc isn't working today...

Edit: On a more serious note, you could use a video editor which shows the sound wave visually and step through in slow motion.

[martino]

Yeah, the video editor idea sounds good. But where could I find a good (and free) one?

[CWR03]

But where could I find a good (and free) one?
There's no such thing.

If you're having to go to this much trouble to even detect whether or not the audio and video are in synch, why even bother with it? Otherwise if you feel you have a number such as -42, try it and see if it's worse. You can also play it in Media Player Classic and adjust the delay until it seems perfect, then use that number to make your final adjustment.

[martino]

Seriously? There is NO video editor which displays the audio wave????

[CWR03]

You asked for a good (and free) one. I've used an older program in the past, Magix Video Deluxe, which does display the audio wave, but it's not free.