Getting Audio from Video Files

This can either be really easy or slightly tricky depending on what your source file is.

Hence, the guide will have the following sections:

1) Getting audio from AVI and mpeg1 video files using Virtualdub
2) Using mpeg2 audio from mpeg2 video files using dvd2avi.
3) Getting audio from locked video codecs such as RealMovie


Let's go!

1) Getting audio from avis and mpeg1 files using Virtualdub

Load your avi or mpg file into virtualdub. If you get an error message that says something about variable bitrate audio then don't worry - we are simply extracting it as an uncompressed wav so everything should be fine.

Go to 'Audio' and select 'Full Processing Mode'

Now, go to Compression and make sure it says <No Compression [PCM]>

Don't change any of the other settings. If you need to change any of the audio properties, it's best to do that afterwards as Virtualdub may not be able to directly convert this type of audio stream.

Select 'File' -> Save WAV… to save your audio stream.

With any luck you should have your audio.

Additional: you can also set the start and end for your audio extraction using the slider under the video but this can be problematic in some VBR streams so use with caution if you are extracting VBR audio.

VBR extraction fix: If for some reason you cannot convert an mp3 vbr stream to uncompressed wav, try selecting Direct Stream Copy in the Audio menu in Virtualdub and then Save Wav. This will export an mp3 file with a wav header (a compressed wav). I would then load this into dBpoweramp Music Converter or Winamp to convert it to uncompressed for editing.

2) Using mpeg2 audio from mpeg2 video files using dvd2avi (not AC3 - see DVD guide).

Load dvd2avi… click File -> Open

You may need to select "*.* all files" if your mpeg2 video is a .mpg or .dat file.

Select the area for extraction using the slider and the "["and "]" buttons (optional).

Select Audio -> Track Number -> 1 (or other if you have a multiple audio channel file)

Now choose File -> Save Project and you will get a dvd2avi project file and a nice .mpa (MPEG audio) file that once renamed to .mp2 can be converted with winamp or dBpowerAMP Music Converter.

3) Getting audio from locked video codecs such as RealMovie

Basically, with any locked codec you are going to have to do it the hard way and sample the audio directly. See the last part of the Using Downloaded Audio guide for a solution to extracting audio from locked sources.

AbsoluteDestiny - June 2002