sync issues with DVD to DivX conversion

[snafubaby]

I used Avi.Net to convert a DVD to DivX. Well, the video and audio are 1900 ms out of sync, according to VirtualDub. I clicked on "audio", then "interleaving", then "audio skew correction", and put the number i figured out, which is 1900. Other than that, the video looks beautiful! Now, what do i do now? Just save the video as a new filename? Or is there more to it than that?

Please help! thanks

[jagabo]

After setting audio skew:

Video -> Direct Stream Copy
Audio -> Direct Stream Copy
File -> Save as AVI

[snafubaby]

After setting audio skew:

Video -> Direct Stream Copy
Audio -> Direct Stream Copy
File -> Save as AVI

well, something's fishy, because i tried what you said, and it's still out of sync. I put in 1900 in the audio skew field. I made sure both video and audio have "Direct Stream Copy", and saved as AVI.

If i can't get this right, I'll just try ripping it again from DVD. Which version of Virtualdub should i be using? Are there any settings with buffering that i should be using? Any other tidbits of info that i should know about?


thanks for the help!

Rick

[jman98]

Well, if you used VBR MP3 as your audio, I would advise against that. VBR audio often causes sync problems. If you're going to make Divx files, it's really better to use CBR MP3 than VBR MP3. The space savings in using VBR over CBR are minuscule and given that VBR audio often doesn't sync up correctly, it's really just not worth it. You may not have used VBR audio (no info in your posts either way), but I just wanted to point this out in case you didn't know it because may programs default to VBR MP3 audio when encoding to Divx.

[jagabo]

i tried what you said, and it's still out of sync. I put in 1900 in the audio skew field. I made sure both video and audio have "Direct Stream Copy", and saved as AVI.

It always works for me. Maybe you need -1900 intead of 1900? Ie, you need to advance the audio not delay it.

[snafubaby]

Well, if you used VBR MP3 as your audio, I would advise against that. VBR audio often causes sync problems. If you're going to make Divx files, it's really better to use CBR MP3 than VBR MP3. The space savings in using VBR over CBR are minuscule and given that VBR audio often doesn't sync up correctly, it's really just not worth it. You may not have used VBR audio (no info in your posts either way), but I just wanted to point this out in case you didn't know it because may programs default to VBR MP3 audio when encoding to Divx.

I didn't find any part of Avi.net that lets you change the DivX configuration from CBR or VBR. Perhaps i'll just try autoGK. I am somewhat experienced in converting DVD to DivX (and XviD), but don't know a lot of the detailed mechanisms, and didn't know that about CBR being best to use. Thanks for letting me know. Note to self: USE CBR!

[snafubaby]

i tried what you said, and it's still out of sync. I put in 1900 in the audio skew field. I made sure both video and audio have "Direct Stream Copy", and saved as AVI.

It always works for me. Maybe you need -1900 intead of 1900? Ie, you need to advance the audio not delay it.

That's the weirdest part. I put in 1900, and the video plays beautifully, in sync with the audio IN Virtualdub. I play a few parts of the file. Everything looks great! Then, i save it, using Direct Stream Copy for both audio AND video. I save it as DivX. Then, when i play it using VLC, or even back in virtualdub, it's out of sync again. Of course, after loading it, i put the audio skew from 1900 back to 0, since it's not out of sync anymore. Or at least i thought it wasn't. I'll see if i can modify the audio bitrate as the previous poster said to do, making sure it is set at CBR.

thanks. I might try a different method if this doesn't work out, maybe AUTOGK.

[jagabo]

That's the weirdest part. I put in 1900, and the video plays beautifully, in sync with the audio IN Virtualdub. I play a few parts of the file. Everything looks great! Then, i save it, using Direct Stream Copy for both audio AND video. I save it as DivX.

Since you are using Direct Stream Copy you have no choice of codecs. All VirtualDub is doing is copying the compressed data from the original file to a new file -- adding the audio skew in the process.

Then, when i play it using VLC, or even back in virtualdub, it's out of sync again. Of course, after loading it, i put the audio skew from 1900 back to 0, since it's not out of sync anymore.

I don't understand. You say the audio is not in sync then you say it is in sync?

[snafubaby]

That's the weirdest part. I put in 1900, and the video plays beautifully, in sync with the audio IN Virtualdub. I play a few parts of the file. Everything looks great! Then, i save it, using Direct Stream Copy for both audio AND video. I save it as DivX.

Since you are using Direct Stream Copy you have no choice of codecs. All VirtualDub is doing is copying the compressed data from the original file to a new file -- adding the audio skew in the process.

Then, when i play it using VLC, or even back in virtualdub, it's out of sync again. Of course, after loading it, i put the audio skew from 1900 back to 0, since it's not out of sync anymore.

I don't understand. You say the audio is not in sync then you say it is in sync?

It's in sync when putting in the 1900 ms audio skew. Then, after saving it, and loading it back in through Virtualdub, it's out of sync again. Before playing it AFTER saving and loading it back in, i make sure the audio skew is set back to 0, because i think it's in sync, and looked to be that way when i saved it using Direct Stream Copy on both audio and video. Then, after loading it back in through virtualdub, it's out of sync again.

[guns1inger]

After saving it, does it play in sync in a media player ? Virtualdub is not a media player, and not the best place to test for audio sync.

[snafubaby]

After saving it, does it play in sync in a media player ? Virtualdub is not a media player, and not the best place to test for audio sync.

It's a miracle!!! I took your advice, and it worked! I saved it and just did trial and error. Then, i figured the magic number, 700ms, and played it with VLC. It is in sync! NOTE TO SELF: Don't try things in virtualdub, as it's not necessarily a media player.

Thanks and Happy Holidays!!!

[guns1inger]

When addressing sync issues I like to use Media Player Classic. The numpad + and - keys allow you quickly adjust the audio and work out the difference. From there you can use whatever tools are appropriate to fix the problem, and MPC to confirm the results.

[snafubaby]

When addressing sync issues I like to use Media Player Classic. The numpad + and - keys allow you quickly adjust the audio and work out the difference. From there you can use whatever tools are appropriate to fix the problem, and MPC to confirm the results.

thanks for the suggestion. I'll definitely give MPC a try. I've used to before, and will try to use it for sync issues.

thanks again!