Lip sync and a wierd thing!

[wolvesandbooze]

I know lip sync has been mentioned so many times on here, to my knowledge no guide really clears this problem up. Well to get to the point. I had a xvid that I wanted to convert to dvd, I opened up the file and got the dreaded warning virtual dub has detected an improper vbr. So I decompressed the audio, then ran it through virtual dub again, no warning this time. I then decided to convert just ten minutes of the divx using the pcm I created for the video and the wav file which I had just ran through vdub. Hey presto when I checked the film was all in sync perfect. So I decided to go for it and converet the lot. I always leave tmpgenc on my screen so I can see whats going on, and after about 15 minutes into the conversion the bloody video just dissappeared, complete black screen, although it was still converting. I thought I'd solved the lip sync prob but I hadn't, any ideas why this happened. By the way I did originally convert the film ignoring the vdub warning and the lip sync was awful. Any help on this matter would gain you a gold star.

[Tommyknocker]

How could I possibly turn down the chance at a gold star?

I know lip sync has been mentioned so many times on here, to my knowledge no guide really clears this problem up.

Choose your poison

Did you check you vidoe for bad frames? If you have, this all I can think of.

[Craig Tucker]

I would say you probrably have a bad frame which is freezing the video when encoding.

[wolvesandbooze]

No bad frames there, wierd eh. But what really puzzles me is when you get the warning fom virt dub if you ignore it it sometimes works anyway, probably about 50% of the time in my case. I've upped the offer now from a gold star to a bottle of scotch whisky to anyone who can solve lip sync probs. This only applies to people in the uk all outside will recieve 20 episodes of the british soap known as crossroads...its great honest.

[Tommyknocker]

Okay, how did you check for bad frames, and do you know how to framserve?

[funkguy4]

Yah, FRAMESERVING ALL THE WAY!!!!

Anyways, make sure you set your source audio in VDub to the PCM (I know, it sounds like advice to a newb), and then frameserve with audio to TMPGEnc. Also, if the bitrate is too high for your computer, or your hard drive is too slow/fragmented, then this can cause desync as well. Have you burned to RW and tried the file in a standalone?

[ZippyP.]

if the bitrate is too high for your computer, or your hard drive is too slow/fragmented, then this can cause desync as well.

Maybe if you're capturing video. In a straight avi to mpeg conversion then bitrate, disk speed and fragmentation are irrelevant as far as a/v sync is concerned.

[ZippyP.]

No bad frames there, wierd eh.

I have had bad frames (and so have other people) that Virtualdub has failed to detect. The only solution was to find the spot where the freeze occurred and manually edit it out.

[funkguy4]

I was talking about audio/video desync at PLAYBACK!

[ZippyP.]

I was talking about audio/video desync at PLAYBACK!

Then I agree with you!

[funkguy4]

Daz kew....