57 lines
755 B
Text
57 lines
755 B
Text
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class:: HPZ1
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summary:: Two point difference filter
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related:: Classes/LPZ1, Classes/HPZ2
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categories:: UGens>Filters>Linear
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Description::
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A special case fixed filter. Implements the formula:
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code::
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out(i) = 0.5 * (in(i) - in(i-1))
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::
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Which is a two point differentiator.
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classmethods::
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method::ar, kr
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argument::in
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The input signal.
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argument::mul
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Output will be multiplied by this value.
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argument::add
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This value will be added to the output.
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Examples::
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code::
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// Compare:
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{ WhiteNoise.ar(0.25) }.play;
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{ HPZ1.ar(WhiteNoise.ar(0.25)) }.play;
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// HPZ1 is useful to detect changes in a signal:
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// see also HPZ2
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(
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{
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var changingSignal = LFNoise0.ar(1000);
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var hpz1 = HPZ1.ar(changingSignal);
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[hpz1, hpz1 > 0, hpz1.abs > 0]
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}.plot
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);
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::
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