Sync question again

vbimport

#1

I know this topic is covered a lot, but could someone please tell me (Bearing in mind I’m a Newbie) where in the process a video is likley to go out of sync. I have an AVI file which I convert using TFM, I have tried a 4 pass method and a DS2RoBa 1 pass, can’t see any quality shift so I’ll stick with the 1 pass. The AVI seams perfectly in sync, but the burnt DVD in out of sync on my computer and even more out of sync on my TV, why is that? Is there a way of ensuring a good sync before burning? As I said I have done various serches on this but most replies seem to be aimed at the experts, of which I am far from being. Thanks Paul


#2

Are you encoding for pal or ntsc. What frame rate are you encoding. What audio format and hz are you using. If ntsc, you should have a frame rate of 29.97, and audio should be ac3 at 48hz. Anything else, and you may be out of sync.


#3

Hi Paul. Quite recently I discovered a pretty easy fix for most sync issues, even on dvd’s I had burned without checking that turned out to have bad sync. Open up your VIDEO_TS folder from your hard-drive (file/open directory) using VLC (videolan) player. Right-click the video window and get to the options or preferences menu. Click on audio and tick the box for advanced options.

There is a box where you can experiment with entering milliseconds to delay or advance your audio. Experiment until you get it in sync and note the number that worked (you have to stop and reopen the file for each value you try to reset it). You use a - sign to input negative values by the way.

Now I import the vobset into DVDLab and use the fix sync tool by entering the value that worked in VLC. This produces a fixed audio stream which will be synced with your movie. I personaly demux the vobset before doing this, then add the video and the fixed audio to a new movie. When you then compile your dvd, everything is back in sync like magic. Even for a newbie, this is much easier than it perhaps sounds!

DVDLab is fully functional free for a months trial. There are other softwares and ways to sync your files, but this is the easiest way for me personaly. I’m sure someone else will go into using virtualdubmod to check if your .avi will go out of sync, even though it plays in sync on your pc, and how to fix it there. I personaly just convert and fix it at the .vob stage now.

Another reason for sync issues can be dropped frames in the encoding process. Gradual sync issues or sync issues in parts of the movie only are harder to fix, but I believe it can be done in an editor like Vegas or Premiere if you have the patience and time to learn.

I’d recommend WinAVI for converting over TFM as well. It’s faster and is great for encoding between PAL and NTSC if that’s what you’re doing. I couldn’t live without 7.6 and DVDLabpro.


#4

harley2ride: I encode as ntsc as i read somewhere that this is slightly better than pal (my DVD player supports both), frame rate is 29.97 and audio AC3 not sure about hz as I can’t see it mentioned in TFM.

d dog: I will try all your suggestions.

Many thanks for replying you two. Paul


#5

Off topic sorry but I need to thank this poster,it solved a long standing problem for me.
Bruce


#6

Happy I was able to help Bruce. It was a long standing problem for me too, and I wish I could have back the disks I’ve previously binned due to it. Well, you live and learn, in the wild and whacky world of video encoding!

Don


#7

Yes it is and I find it it cost money you(me in this case) learn very soon,again thanks I was in heven when the sync prb. went away.
Bruce


#8

Wrong syncs with “avi” files mostly come from the usage of VBR audio.


#9

How do I know if it’s VBR or CBR?


#10

Open it with Gspot ( http://www.headbands.com/gspot/ )and look under the audio tab. It will tell you if it is VBR or CBR. This difference does not always cause a problem though.


#11

VBR files to me have more errors and I try to avoid them (thro you can not).
Bruce