109 lines
1.4 KiB
Text
109 lines
1.4 KiB
Text
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#lang scribble/manual
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@(require (for-label racket))
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@title{PeakFollower}
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Track peak signal amplitude.@section{related}
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Classes/Peak
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@section{categories}
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UGens>Analysis>Amplitude
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@section{description}
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Outputs the peak amplitude of the signal received at the input. If level
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is below maximum, the level decreases by the factor given in
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@racketblock[decay:: .
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Internally, the absolute value of the signal is used, to prevent
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underreporting the peak value if there is a negative DC offset. To obtain
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the minimum and maximum values of the signal as is, use the
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link::Classes/RunningMin:: and link::Classes/RunningMax:: UGens.
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]
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@section{classmethods}
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@section{method}
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ar, kr
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@section{argument}
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in
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The input signal.
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@section{argument}
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decay
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Decay factor.
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@section{Examples}
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@racketblock[
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s.boot;
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// no decay
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(
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{
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SinOsc.ar(
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PeakFollower.ar(Dust.ar(20, Line.kr(0, 1, 4)), 1.0) * 1500 + 200,
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0, 0.2
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)
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}.play;
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)
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// a little decay
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(
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{
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SinOsc.ar(
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PeakFollower.ar(Dust.ar(20, Line.kr(0, 1, 4)), 0.999) * 1500 + 200,
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0, 0.2
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)
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}.play;
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)
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// mouse x controls decay, center of the
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(
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{
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var decay;
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decay = MouseX.kr(0.99, 1.00001).min(1.0);
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SinOsc.ar(
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PeakFollower.ar(Dust.ar(20), decay) * 1500 + 200,
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0, 0.2
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);
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}.play;
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)
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// follow a sine lfo, decay controlled by mouse x
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(
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{
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var decay;
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decay = MouseX.kr(0, 1.1).min(1.0);
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SinOsc.ar(
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PeakFollower.kr(SinOsc.kr(0.2), decay) * 200 + 500,
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0, 0.2
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)
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}.play;
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)
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::
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]
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