How to stretch audio by 1 second

[1loser]

The audio is in sync at the very beginning but off by about 1 second at the end. I think the frame rate of the DivX source was 29.971 and I used AssumeFPS(29.970,True) in the avs script file. DVD2SVCD inserted that line so I left it there.

I would like to stretch the audio by about 1 second. Can this be easily done? I'm trying to avoid re-encoding the video. I have sound forge and cool edit but maybe virtualdub could be used when extracting the wav file.

Just to emphasize, I don't want to delay the audio.

Thanks in advance.

[Swede]

Cool Edit can easily do that.. (Transform/Time/Stretch) But if you don't have the original wav you have to reencode.

[PeterTheMaster]

why dont you just change the framerate of your video? this has nothing to do with reencoding. it just defines the playback speed.

if you still want to stretch the audio (which i wouldnt recommend in this situation) i recommend resample in cool edit and paste
100.00333667000333667000333667 into the percentage field. i dont know how many digits it parses, but sure more than it displays. i was only 2 samples off after 2 hours at 48kHz, thats an accuracy of 99.9999994%!

[1loser]

Originally posted by Swede
Cool Edit can easily do that.. (Transform/Time/Stretch) But if you don't have the original wav you have to reencode.
Thx for the info. I checked Sound forge and it also has the same feature. I think I need to stretch it only 1/4 to 1/2 sec. It seems sound forge didn't like 1/4 sec but worked for about 1/2 sec.

[1loser]

Originally posted by PeterTheMaster
why dont you just change the framerate of your video? this has nothing to do with reencoding. it just defines the playback speed.

if you still want to stretch the audio (which i wouldnt recommend in this situation) i recommend resample in cool edit and paste
100.00333667000333667000333667 into the percentage field. i dont know how many digits it parses, but sure more than it displays. i was only 2 samples off after 2 hours at 48kHz, thats an accuracy of 99.9999994%!
I took the frame rate of 29.971 and divided it by 29.97 and got the same value you recommended of 100.00333 but was trying to use .25 sec which is the same in this case.

I'm playing it on my standalone DVD player so I think changing the framerate of my video doesn't apply, correct?

Sound forge will take .25 sec or 100.0033% but when I save it the file is still the same until I use .5 sec which is too much. Cool edit will take 100.0033 but locks up on me every time at about 50 to 80%.

[PeterTheMaster]

i never had a standalone. but it sounds right that they have a certain fixed framerate.

i dont know why your cool edit crashes, mine works. they have a nice forum on the syntrillium homepage where u get fast answers usually.

as i said: i would paste the entire long number to make the result as accurate as possible.

[1loser]

Originally posted by PeterTheMaster
i dont know why your cool edit crashes, mine works.
I finally got it to work by using the pro version. I was using cool edit 2000 and it keep locking up. When I went to uninstall it I got a message saying it was installed twice.

Adding 1/4 sec worked perfectly! Sound forge 5.0 wasn't able to use less than 1/2 a sec, at least I couldn't get it to.

thx for the help.

[Cradle22]

And don't forget: There is always this nice small tool named Wave Length Adjust (WLA), which ist faster & often more accurate than all sound editing programs out there...

It simply duplicates audio frames (if stretching) or deletes some (if shortening), both are unhearable changes... It helps me out a lot because I'm always muxing more than one auio track to a video source...

[PeterTheMaster]

i dont like duplication or deleting samples, it damages the audio intentionally.
resampling is much better and really accurate in cool edit.

[1loser]

Originally posted by PeterTheMaster
i dont like duplication or deleting samples, it damages the audio intentionally.
resampling is much better and really accurate in cool edit.
I was amazed that I was able to stretch a 124 minutes audio file by 1/4 sec and the results were excellent!
Originally posted by Cradle22
There is always this nice small tool named Wave Length Adjust (WLA), which ist faster & often more accurate than all sound editing programs out there...

It simply duplicates audio frames (if stretching) or deletes some (if shortening), both are unhearable changes... It helps me out a lot because I'm always muxing more than one audio track to a video source...
I tried "Wave Length Adjust (WLA)" and the results were terrible!