45 lines
1.3 KiB
Text
45 lines
1.3 KiB
Text
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#lang scribble/manual
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@(require (for-label racket))
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@title{(peak-follower in decay)}
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Track peak signal amplitude. outputs the peak amplitude of the
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signal received at the input. If level is below maximum, the level
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decreases by the factor given in decay.
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in - input signal.
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decay - decay factor.
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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
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obtain the minimum and maximum values of the signal as is, use the
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running-min and running-max UGens.
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No decay
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(let* ((s (mul (dust ar 20) (line kr 0 1 4 do-nothing)))
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(f (mul-add (peak-follower s 1.0) 1500 200)))
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(audition (out 0 (mul (sin-osc ar f 0) 0.2))))
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A little decay
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(let* ((s (mul (dust ar 20) (line kr 0 1 4 do-nothing)))
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(f (mul-add (peak-follower s 0.999) 1500 200)))
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(audition (out 0 (mul (sin-osc ar f 0) 0.2))))
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Mouse x controls decay
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(let* ((x (mouse-x kr 0.99 1.0001 1 0.1))
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(s (mul (dust ar 20) (line kr 0 1 4 do-nothing)))
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(f (mul-add (peak-follower s (u:min x 1.0)) 1500 200)))
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(audition (out 0 (mul (sin-osc ar f 0) 0.2))))
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Follow a sine lfo
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(let* ((x (mouse-x kr 0.99 1.0001 1 0.1))
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(s (sin-osc kr 0.2 0))
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(f (mul-add (peak-follower s (u:min x 1.0)) 200 500)))
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(audition (out 0 (mul (sin-osc ar f 0) 0.2))))
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