Audio synch problem

[King-Of-DK]

Does anybody know how to correct this little problem. Every time i convert an AVI using TMPGenc the MPG file is out of synch,it start fine,then as the movie progresses the synch problem gets worse.I use VirtualDub to extract and convert the audio from 48000hz to 44100hz,but sometimes when i load a file Virtualdub says that is has detected an improber VBR and that it may introduce X number milliseconds of skew,and that i have to reencode with a constant bitrate encoder,i have never reencoded the audio and it has worked fine,but lately i get the synch problem on files that virtualdub thinks is fine..to make a long story short,does anybody have a *.VCF file that i can load and fix this problem,or do i really have to reencode the audio?

[Craig Tucker]

Use vdub to save the audio as a wav file, then use this wav file as your audio source when you encode to mpeg.

Craig

[King-Of-DK]

vdub,is that better than Virtualdub or is it the same,i am using virtualdub to extract the wave,if you bothered to read my post..

[KingJohn]

vdub,is that better than Virtualdub or is it the same,i am using virtualdub to extract the wave,if you bothered to read my post..

I was about to reply until I seen that

[King-Of-DK]

Seen what??

[Temil]

First off, dont get upset or confused. It's really easy to do all this, just takes a little time. Now, head over to the following url and read everything all the way. Dont do anything just yet, just read it so you understand it. Only ready on this page from
"Now start Virtualdub. ..... " which is on top and
"Save the wav by clicking on Save WAV..... " which is about half way.

http://www.vcdhelp.com/virtualdubaudio.htm

Done reading it allready? .... GOOD!
Now, head over to another url listed below and read from
"Guide" which is near the top and
"Now you are ready...." which is near the midway to bottom.

http://www.vcdhelp.com/tmpgencsvcd.htm

Damn your fast! .. Ok, now just follow all those steps, and everything will work out. Trust me! .. I recommend you clip the movies top and bottom black sections, because the final MPG will add them automaticly, and make sure you pick the option "Full Screen (Keep Aspect Ration)" ..
That should do it for ya. If ya have any more problems, just let me know!
I'll keep an eye on this post for ya! =)

}Temil{

[King-Of-DK]

First of,thanks for the answer,but i know how to convert movies,i always do as the guide says,except i can´t use SVCD in my Pioneer 717,and trust me when i say,i have now converted a lot of movies with no problem,but now i got these probelms with the sound,where it gets out of synch over the period of the film,and THAT i cannot fix..

[Temil]

hmm, are you able to play VCD's on your DVD player?

[King-Of-DK]

yes i can..

[Temil]

then why not just convert from avi over to VCD , not avi to SVCD

[King-Of-DK]

Thats what i have been doing all along

[Temil]

in a past post, you stated that you extracted the audio from the AVI file. Now let me ask, have you played the AVI file all the way to the end first, to just see if anything is out of sync within the avi. I recently ran across that problem myself. also, you are extracting audio with out any compression, right?

on another note, you are checking the video FPS within the AVI and picking the same FPS for VCD, right?

Also, try to make a SVCD - MPG-2 file, not a VCD - MPG-1 file. I have noticed that some, not many but some of the divx files dont convert to well from AVI to MPEG-1, but it convert fine over to MPEG-2
just something to try.

[King-Of-DK]

i always check the AVI,and ofcourse i use the same FPS,i load the templates that corresponds with the FPS.I have no use for MPG-2,as my DVD player doesn´t support it.I extract the audio with full processing and no compression

[bugster]

when i load a file Virtualdub says that is has detected an improber VBR and that it may introduce X number milliseconds of skew,and that i have to reencode with a constant bitrate encoder,

in this case, use virtualdub to extract the audio unchanged. To do this use audio->direct stream copy. file->save wav.

Then use BeSweet or Headac3he to convert the audio to uncompressed wav (and do sample rate conversion if req'd)

Hope this helps

[King-Of-DK]

I thought that Headac3he only where used with AC3? Why exactly do i need to convert the uncopressed Wav,as it already is an uncompressed wav from Vdub

[bugster]

As I said, do this when vdub complains about VBR audio format as it is one of the few things vdub does not handle well. Headach3e and Besweet can handle VBR (mp3) audio formats better and so it may help resolve you gradual loss of synch. I doubt it will help with initail sync offset problems but they are easily fixed!

[King-Of-DK]

Hey bugster thanx for the answer,but what is "initail sync offset",and if i get you right,i use vdub to extract and haedac3che to convert it? How exactly is that done? Do i do the same thing as with ac3 files??

[bugster]

Hey bugster thanx for the answer,but what is "initail sync offset",and if i get you right,i use vdub to extract and haedac3che to convert it? How exactly is that done? Do i do the same thing as with ac3 files??

By "initail sync offset" I mean if the audio is out of sync by a fixed amount throughout the movie, then you can fix this in either vdub or TmpGenc quite easily.

As I said, use vdub to extract, using 'direct stream copy'. This will give you a file containing the audio part of the avi eaxactly as encoded in the original file. The file will be given a .wav extension by vdub, but in this case it is not reall a wav file, but a VBR MP3 I would guess.

Yep (AFAIK) both Headac3he and BeSweet will convert VBR MP3 to wav, and do sample rate conversion, just take a close look at the settings before hitting start.

[Daagar]

http://forum.vcdhelp.com/viewtopic.php?t=100390

[DRfrankenpimp]

load your avi into vd then select direct stream copy,then select framerate if the audio and video have different frame rates to match duration select that then resave the avi with the new frame rate then load into tmpegenc this allways works for me

[King-Of-DK]

How can i see what framerates the audio and video has? Thank you guys,now it seems we can all get perfect avi´s.i have tried to get a solution for this problem for a long time,and now it seems like i finally did find it,so THANK YOU,YOU ARE MY HEROES.

[DRfrankenpimp]

in virtual dub look under the video menu

[King-Of-DK]

So what i do is make it change the framerate so that audio and video durations match?What will that do to the excisting framrate(23,976)? will this be corrected when coverting it in TMPGenc? And this should only be done when the converted mpg is out of synch,right? Beacuse almost every time i load an AVI into VDub it says that audio is out of skew..

[DRfrankenpimp]

it will change the frame rate but tmpeg will adjust it properly