support 3channel wavs
kritzikratzi opened this issue · comments
support for 3channel wavs woul be very nice.
necessary changes:
- update the resampling pipeline (3rd channel must be available, but discarded before playback)
- add an option to enable/disable z-modulation when there are three channels
- update the shader accordingly
Hi Hansi, I'll go ahead and comment here. In a typical oscilloscope, Z modulation controls the brightness of the beam. It is a unipolar signal in the positive domain only (although I don't see why the digital version couldn't simply wrap everything in a bipolar signal around into positive brightness values again). I would love to see support for this for a live audio input stream, so that it could be better integrated with my Vector Synthesis project. Thanks!
imho -1..0 being a reduction in brightness and 0...1 a boost in brightness seems intuitive given how digital audio values are stored.
Yes that makes sense!
I guess that would sum with whatever value the GUI has set for the brightness?
i'm guessing a multiplication with a^z with some fixed a, but not sure.
should be easy enough to derive the actual equation by taking a few pictures of the effect on a scope.
i went for 0...1, making it darker (as i said earlier) actually makes no sense, because it's already invisible at 0 :)
for now i'm clipping that range (ie less or equal zero is invisible).
liveinput has no channel selector, so for now this works with file input only.
sending you a binary in a bit.
clsoing this because ... it's already in the master branch and seems to work (just not publicly released yet, but that's another story).