57 lines
1.5 KiB
Text
57 lines
1.5 KiB
Text
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class:: Unpack1FFT
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summary:: Unpack a single value (magnitude or phase) from an FFT chain
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categories:: UGens>FFT
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related:: Classes/PackFFT, Classes/UnpackFFT
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Unpack1FFT(chain, bufsize, binindex, whichmeasure=0)
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description::
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Takes an FFT chain and extracts a single scalar value as a demand-rate stream. To call it you need a "demander" which fires whenever the FFT chain fires - this is normally achieved using link::Classes/PackFFT:: but can also be done using link::Classes/Demand::.
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Note::
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The main purpose of this UGen is as a component in pvcollect, pvcalc, and pvcalc2 processes. You're welcome to use it on its own - the example below shows basic usage. But most people won't typically need to use it directly.
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::
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classmethods::
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private:: categories
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method:: new
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argument:: chain
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an FFT chain
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argument:: bufsize
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the size of the expected input FFT frames
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argument:: binindex
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the integer index of the bin you want to query
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argument:: whichmeasure
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0 for magnitude and 1 for phase. None of these arguments can be modulated.
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examples::
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code::
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(
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s.waitForBoot({
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c = Buffer.read(s, Platform.resourceDir +/+ "sounds/a11wlk01.wav");
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})
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)
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// Let's extract the DC component - i.e. the magnitude at index zero.
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(
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x = {
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var fftsize = 1024;
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var sig, chain, unp;
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sig = PlayBuf.ar(1, c, BufRateScale.kr(c), loop: 1);
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chain = FFT(LocalBuf(fftsize), sig);
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unp = Unpack1FFT(chain, b.numFrames, 0, 0);
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// Demand some data from the unpacker
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Demand.kr(chain>=0, 0, unp).poll(chain>=0, "unpacked value");
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(sig*0.1).dup;
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}.play(s);
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)
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x.free;
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::
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