Audio Synch...Help!!

[shiroamakusa]

I am encoding an anime DVD, Ceres: The Celestial Legend Vol. 6. I encoded vol. 5 with no problems at 23.9x framerate, no audio probs, nothing. But on this new title I cannot get the audio to synch up. It starts up fine, but then about 25 minutes into the movie (after the first episode) the video gets ahead of the audio. I have tried (using FlasK .60) encoding together in MP3, encoding together in PCM audio and converting using virtual dub, I lowered the framerate from the detected 29.97 to 23.9x to try to duplicate my other success...no go. The audio gets out of synch at the same general part.

I am using FlasK because of the subtitles option. They appear fine and in the right place. I am trying to make a simple one-file avi with subtitles (one dvd-one cd) to send to my wife who's deployed (military). If anyone can help me, I appreciate it. Right now I am encoding the video and audio separate, will be converting the AC3 to wav then converting the wav to mp3 with vdub and combining. i hope this will work.

[Kaiser-Soze]

I have ripped a lot of DVD's using the settings below and I never had a problem. Try them ;)

Use Virtual Dub
Use MP3 Audio Format 128 Kb or more
Use Preload every ------> 500ms
Use Interleave --------> 500ms
DO NOT CHANGE THE FRAME RATE
That causes the problem 99%
When u get Audio/Video Synch problems
try to change the interleaving and preloading
Use the above settings and if they don't work and the Audio is skippy lower the interleaving value if the Video is raise it

[_dk]

same problem here on two movies

sound is synced fine until approx: 27 minutes
then it suddenly goes out of sync.

the divx movie is made with flaskmpeg 0.60

any idears of what goes wrong ?

[UncasMS]

flask + audio encoding => crap

do NOT use flask (at all) or at least not for the audio part!!

try what kaiser-soze suggested!

[_dk]

thanks for your answer

i made a divx movie with perfect sound using Xmpeg Encoder

(havent found out how to use virtualdup yet)

now i just have to figur out the 2 pass way of encoding
without getting very large files ?

[UncasMS]

the best tool should be nandub using divx3

due to its internal routine, you dont need a (blurry and resource-killing) codec like divx4 but instead you can use good ole divx3.

nandub will reach your desired final filesize MOST precisely (divx4 wont) and due to its two pass routine will give you best possible quality.

in case you read german, take a look at the nandub part of my guide (havent translated that part, because i dont deal with ntsc an ivtc and thus an english version would be incomplete).

[cgi2]

The audio sync problem likely is occurring at a vob file boundary. Verify this. If this is so, process each vob file seperately; then clip the last end of each resulting file (except the last one); clip about 1 second off using virtualdub, then join the pieces.

I've experienced this problem many times and it's due to differing lengths of audio and video in the source. flask doesnt automatically fill in the gaps in the resulting audio, it appears.

[UncasMS]

if the vobs were to blame, then why does this not occur while using nandub or gordian knot?

[cgi2]

Originally posted by UncasMS
if the vobs were to blame, then why does this not occur while using nandub or gordian knot?

Perhaps these other tools fill in gaps in the audio stream. I dont know enough to tell if this is a reasonable explanation....

[Quicksix]

If you've installed the Radium hacked Fraunhofer CODEC and if you are using XMPEG and making sure to check 'compensate for Fraunhofer bugs' then it shouldn't give you any problem. The fact that you are experiencing difficulty seems to lend support to the idea that it has something to do with the Vobs. I do agree with Uncas though, XMPEG/Flask is not really the best tool to use for processing audio....tends to create really poor surround compatible downmixes. I am assuming that this is an Anime and that it is encoded at 29.97fps interlaced. I have heard different people offer examples of how certain IVTC implementations can be very buggy and thus cause problems with keeping synch. Perhaps this is occuring at the vob boundaries? Any thoughts on this?

Quicksix