VirtualDub, Cutting, VBR Error

[eli2k]

When I load VirtualDub v1.4.10 and my AVI I just made in GordianKnot, it gives me an error saying that VD detected an improper VBR audio encoding in the source AVI file and will rewrite the header with a standard CBR during processing. It will create 14721 ms of skew from the video stream and says if I don't like it I have to decompress the whole audio stream to WAV and recompress with a constant bitrate encoder. bitrate: 157.5 +/- 15.3 kps (HUH?)

Arg, do I have to do is all over again? I can see the movie fine. It plays fine and the audio is okay. BUT, it looks a little off sometimes. Maybe I should reencode with a CBR instead of VBR? Maybe CBR of 128/160? Which is better, anyways? Maybe I should have taken the 2 channel stream, too... So do you think I should reencode the whole thing?....or try to fix it up?

Thank you.

[Enchanter]

Use nandub instead. It supports VBR MP3 streams.

[eli2k]

Hmm, that seems to work. Thanks.

However, it looks like my divx seems to freeze at certain points. Like the video freezes and then continues, which is annoying. Maybe I should reencode it. Is the audio better in CBR or VBR?

[Enchanter]

Glad to have been of some help.

As to your freezing problem, does it occur in the original video as well? Direct Streaming the videos should not result in any freeze frames.

For audio, I try to use high-bitrate MP3 whenever possible. My choice is LAME APS (--alt-preset standard), which results in VBR MP3 at around 192 kbps or lower, depending on the quality of the original sound source.

[eli2k]

No. When I watched the movie from the ripped VOBs on my hard drive on PowerDVD, it played perfectly. However, in this one, sometimes it freezes. And sometimes in Media Player 7 when I seek to another time frame, like click on that time seek line to the middle of the movie, I have to hear sounds for like 5 seconds before the video starts moving again. :/ - this happens with the original AVI and the newly split AVI.

How would I use a LAME encoder if I'm running Gordian Knot, which uses BeSweet (I think)? Do I disable the BeSweet thingy and then LAME will take over?

Also, would the encoding be ruined if I did the following while it was encoding in VirtualDub?
- Connecting/Disconnecting from internet (I use a 56k modem and the computer sort of freezes a little bit when opening a connection)
- Changing the priority thread in the WinXP Task Manager from Low to Idle to High to Normal, etc
- Changing priority thread in VirtualDub from Low to Higher to Normal, etc.
- Every time I change the priority, it freezes as it tries to update itself...

[Enchanter]

I see. Your original AVI file does contain freeze frames. I'm not too sure of a good solution for this, but you might want to give DivFix a try. I had a few AVIs with freeze frames and the program solved them all.

I always process the audio separately, regardless of what methods I use for creating my videos. I'd always create my MP3 file first and then determine what video bitrate to use (using a bitrate calculator and the knowledge of the MP3 file size). Once I have both my soundless AVI and MP3 files, I simply mux them together using nandub. Works like a charm to me.

And lastly, regarding the priority changes, I have never had any problems (nor slowdowns) when doing so. I try, though, not to go higher than normal. Most of the time I set VD and nandub to idle so that I can go about my other (non-CPU intensive) tasks.

[eli2k]

Hmm, is there a tutorial that would do that (show how to convert AC3 to MP3 and find the correct bitrate and stuff)? I'm just using Gordian Knot and letting it do whatever it does. Would I still be using Gordian Knot then, or would I be doing all this stuff separately?

[Enchanter]

show how to convert AC3 to MP3 and find the correct bitrate and stuff

Check this collection of audio guides.

Since you're already using GK, things will be much more simple. Simply use GK's built-in calculator and input your desired final AVI filesize along with your MP3 file. GK will display the video bitrate to use. The next things you need to do are any other basic tasks that you need to do (cropping, resizing, etc.) and start your encoding.

[VanDine]

Originally posted by eli2k
Hmm, is there a tutorial that would do that (show how to convert AC3 to MP3 and find the correct bitrate and stuff)? I'm just using Gordian Knot and letting it do whatever it does. Would I still be using Gordian Knot then, or would I be doing all this stuff separately?

http://www.doom9.org/index.html?/ac3tomp3.htm

I used this guide here, I think GK uses this engine but its command line only, you have to download GUI for the prog (BeSweetGUI0.6b60.zip from link in the guide) and then you can pick your options and do whatever, the guide advises 128kbps for your MP3s
You'd do this separately but if you put your mp3s into GK working directory where rest of files are, you can continue with GK... read this guide http://www.atlandide.net/~uncasms/en...p?page=gordian to find out how to use your mp3s in GK instead of ac3s


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