36 lines
972 B
Text
36 lines
972 B
Text
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#lang scribble/manual
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@(require (for-label racket))
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@title{subsample-offset}
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demonstrate cubic subsample interpolation, an impulse train that can be moved between samples
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(with-sc3
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(lambda (fd)
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(send-synth
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fd
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"s"
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(letc ((out 0)
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(add-offset 0))
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(let* ((i (mul (impulse 2000 0) 0.3))
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(d sample-dur)
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(x 4)
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(o (add (sub 1 subsample-offset)
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(mouse-x 0 add-offset 0 0.1)))
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(r (delay-c i (mul d (add 1 x)) (mul d (add o x)))))
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(offset-out out r))))))
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Create two pulse trains one sample apart, move one relative to the
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other. When cursor is at the left, the impulsese adjacent, on
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the right, theye exactly 1 sample apart. View this with an
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oscilloscope.
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(with-sc3
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(lambda (fd)
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(let ((t (utcr))
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(dt (/ 1 (server-sample-rate-actual fd))))
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(send fd (bundle (+ t 0.2)
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(list (s-new1 "s" -1 1 1 "addOffset" 3))))
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(send fd (bundle (+ t 0.2 dt)
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(list (s-new1 "s" -1 1 1 "addOffset" 0)))))))
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