From: David S. <ds...@sc...> - 2003-06-30 20:28:56
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On Mon, Jun 30, 2003 at 01:15:24PM -0400, Leif Johnson wrote: > The audioconvert plugin changes stereo to mono by averaging, right ? And > mono to stereo conversion is just duplication ? Seems like any other > methods would be less generally useful and require an app to use a > mixmatrix for proper mixing of different channels. > > But if we extend that to multiple channels, I don't see why the > audioconvert plugin couldn't do a simple average of N interleaved input > channels to one output channel, and be able to duplicate one input channel > to N interleaved output channels. Again, if the app requires more precise > control over the mixing levels, it should use a mixmatrix. Thoughts ? This seems like a reasonable simple approximation of doing the right thing. Changing stereo to mono by averaging the two channels is wrong. However, in many situations, it yeilds acceptable results, which I think is good for a simple element. A more correct algorithm involves converting to a frequency-space representation and adding the amplitudes of the right and left channels for each frequency. Then you need to pick a phase for the resultant signal, which can be a bit tricky. dave... |