Log in

View Full Version : In need of a "voice over" audio filter...


Jocko Homo
5th December 2006, 22:54
I need an avisynth function that can take two audio tracks (or channels, or whatever they're called) and mix them together in such a way that one channel can always be heard above the other.

The purpose of this is for movie voice overs, like a commentary track. The commentary track will be mostly silence except for the periodic but sparse times when something is said. You obviously want to hear the movie while it's playing except whenever the voice over track actually has some... voice over, in which case, you want to hear the voice over track above the movie track.

So, I need an audio filter (or function, or whatever they're called) that will mix two audio tracks, A and B, such that A is at full volume whenever B is silent but then lower the volume of A whenever B is not silent.

Does such a filter exist? If it doesn't, I'd be willing to write one if anyone can point me to some avisynth plug-in development documentation.
Thank you...

unskinnyboy
6th December 2006, 18:57
MixAudio() (http://www.avisynth.org.ru/docs/english/corefilters/mixaudio.htm).

Jocko Homo
7th December 2006, 20:20
MixAudio() (http://www.avisynth.org.ru/docs/english/corefilters/mixaudio.htm).Unfortunately, this filter isn't good enough. I need something that will dynamically change the volume of one track based on the instantaneous (calculus, anyone?) volume of the other track while mixing them. MixAudio() has no such capability...
Again, does such a filer exist? Thank you...

Mug Funky
8th December 2006, 05:13
you'll probably need to use an audio editing program for that.

the avisynth plugin "soxfilter" has a compander that you can use along with mixaudio, but for it to sound any good, you'll want to dip the movie audio manually. adobe audition works pretty well for this, and can load avs files (so you can ensure everything's in sync, and you could even record the commentary as the video plays out of audition if you have a TV out and a nice studio).