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EpheMeroN
15th September 2005, 19:07
I tried the doom9 method and it did not work. I loaded the XviD AVI into Nandub because the audio is VBR MP3. I went to Audio Settings and set it to Full Processing Mode. When I click on Save WAV... it just disappears. Nothing saves. But if I put it back to Direct Stream Copy, I end up with an 81.1mb audio.wav file. I assume it just copied the mp3 and gave it a wave header? If I just took that audio.wav and renamed it to audio.mp3 and then decompressed say in CDex or any app that can decompress mp3 files, would that work as well? I just don't want to end up with out of sync audio.

unskinnyboy
15th September 2005, 19:26
Load the avi into AVI-Mux GUI.Highlight the file and press 'generate data source from files'
The audio track (+ other streams if any) within will appear in the window below.
Select the MP3 track, right click on it and select 'extract binary'.
Save as whatever.mp3.

setarip_old
15th September 2005, 19:57
As an alternative, I beleive you should be able to load your .AVI into VirtualDubMOD, click on the "Streams" dropdown menu, highlight your .MP3 audiostream, and select "Demultiplex"...

EpheMeroN
15th September 2005, 20:34
VirtualDubMod pops up that VBR MP3 warning just like VirtualDub does, saying that it'll rewrite the header which can cause xxxxxx of audio skew or something of that nature.

I'll give that AVI-Mux GUI a try. Once it's as an .mp3 file, any decompressor application will work yes?

Boulder
15th September 2005, 20:44
AVIMux GUI is also a gazillion times faster than VDubMod when extracting audio.

EDIT: Yes, any decompressor will do, it's a regular MP3 file.

setarip_old
15th September 2005, 21:10
VirtualDubMod pops up that VBR MP3 warning just like VirtualDub does, saying that it'll rewrite the header which can cause xxxxxx of audio skew or something of that nature.

And just say "No" to the offer to alter the audiostream - and then follow my earlier instructions...

EpheMeroN
15th September 2005, 21:56
Thanks a bunch guys. Both methods work well, but the AVI-Mux GUI method is indeed much much faster. Cheers!

echooff
18th September 2005, 14:10
Wether it is faster or not depends on what you want to do with the output. If you intend to encode the audio to a different format it would be better to encode it from a wave file (which would make the Vdub method a step saver). Compressed audio to compressed audio is never a good idea.

Boulder
18th September 2005, 14:26
Compressed audio to compressed audio is never a good idea.
In what way, please?

I use MADPlay to decode mp3 streams to WAV to ensure good, reliable and fast decoding.

echooff
18th September 2005, 14:44
going directly to wave using Virtualdub IMO saves time because you are extracting directly. I like and use Avimux_gui, but you still need to go to wave once you have extracted a vbr mp3 using another program. Should you want to keep the vbr mp3 then of course it is much faster. I must admit the virtualdub direct method does not always work, while the avimux_gui method has worked every time.

Boulder
18th September 2005, 14:57
Then again, there's BeSweet which supports going straight from mp3 to the other formats it supports. I don't know how well it works though.

Out of interest, is saving an mp3 file to wav as slow as extracting the mp3 track in VDub? I also noticed that sometimes extracting the mp3 track went really fast, other times it could take more than 10 minutes :confused:

echooff
18th September 2005, 15:19
Yes it is as slow. It seems to be slower when extracting a vbr mp3. Encoding from one compressed audio strait to another is a invitation to problems. I have always ended up with audio problems when trying to do this and ended up going to wave first anyway. That is why I always decompress to wave first.

stephanV
18th September 2005, 15:47
There should be no difference between going from compressed to compressed right away or going to wav as intermediate steps. The decoder will give the exact same output and the encoder will get the exact same input.

echooff
18th September 2005, 16:02
The key word there is should. It is not always a problem but it frequently is. I am by no means a audio expert and don't claim to be, just stating my observations.

stephanV
18th September 2005, 16:22
I can only say I have never had problems with it.