rsc3/doc-schelp/HelpSource/Classes/PeakFollower.schelp

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