/usr/share/SuperCollider/HelpSource/Classes/Unpack1FFT.schelp is in supercollider-common 1:3.8.0~repack-2.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 | class:: Unpack1FFT
summary:: Unpack a single value (magnitude or phase) from an FFT chain
categories:: UGens>FFT
related:: Classes/PackFFT, Classes/UnpackFFT
Unpack1FFT(chain, bufsize, binindex, whichmeasure=0)
description::
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::.
Note::
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.
::
classmethods::
private:: categories
method:: new
argument:: chain
an FFT chain
argument:: bufsize
the size of the expected input FFT frames
argument:: binindex
the integer index of the bin you want to query
argument:: whichmeasure
0 for magnitude and 1 for phase. None of these arguments can be modulated.
examples::
code::
(
s.waitForBoot({
c = Buffer.read(s, Platform.resourceDir +/+ "sounds/a11wlk01.wav");
})
)
// Let's extract the DC component - i.e. the magnitude at index zero.
(
x = {
var fftsize = 1024;
var sig, chain, unp;
sig = PlayBuf.ar(1, c, BufRateScale.kr(c), loop: 1);
chain = FFT(LocalBuf(fftsize), sig);
unp = Unpack1FFT(chain, b.numFrames, 0, 0);
// Demand some data from the unpacker
Demand.kr(chain>=0, 0, unp).poll(chain>=0, "unpacked value");
(sig*0.1).dup;
}.play(s);
)
x.free;
::
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