20 lines
573 B
Text
20 lines
573 B
Text
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#lang scribble/manual
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@(require (for-label racket))
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@title{(zero-crossing in)}
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Zero crossing frequency follower.
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outputs a frequency based upon the distance between interceptions
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of the X axis. The X intercepts are determined via linear
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interpolation so this gives better than just integer wavelength
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resolution. This is a very crude pitch follower, but can be useful
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in some situations.
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in - input signal.
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(let* ((a (mul (sin-osc ar (mul-add (sin-osc kr 1 0) 600 700) 0) 0.1))
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(b (mul (impulse ar (zero-crossing a) 0) 0.25)))
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(audition (out 0 (mce2 a b))))
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