85 lines
2 KiB
Racket
85 lines
2 KiB
Racket
#lang scribble/manual
|
|
@(require (for-label racket))
|
|
|
|
@title{(convolution2 in bufnum trigger framesize)
|
|
|
|
#|
|
|
|
|
Strict convolution with fixed kernel which can be updated using a
|
|
trigger signal.
|
|
|
|
in - processing target
|
|
bufnum - buffer index for the fixed kernel, may be modulated in
|
|
combination with the trigger
|
|
trigger - update the kernel on a change from <=0 to >0
|
|
framesize - size of fft frame, must be a power of two. convolution
|
|
uses twice this number internally, maximum value you
|
|
can give this argument is 2^16=65536. Note that it gets
|
|
progressively more expensive to run for higher powers!
|
|
512, 1024, 2048, 4096 standard.
|
|
|
|
|#
|
|
|
|
(with-sc3
|
|
(lambda (fd)
|
|
(for-each
|
|
(lambda (b)
|
|
(async fd (b-alloc b 2048 1)))
|
|
(list 10 11 12))
|
|
(for-each
|
|
(lambda (n)
|
|
(send fd (b-set1 10 (+ (* 400 n) 100) 1)))
|
|
(enum-from-to 0 2))
|
|
(for-each
|
|
(lambda (n)
|
|
(send fd (b-set1 11 (+ (* 20 n) 10) (random 0 1))))
|
|
(enum-from-to 0 49))
|
|
(for-each
|
|
(lambda (n)
|
|
(send fd (b-set1 12 (+ (* 40 n) 20) 1)))
|
|
(enum-from-to 0 19))
|
|
(send-synth
|
|
fd "c"
|
|
(letc ((k 0) (t 0))
|
|
(let ((i (impulse ar 1 0)))
|
|
(out 0 (mul (convolution2 i k t 2048) 0.5)))))))
|
|
|
|
(define send-to
|
|
(lambda (m)
|
|
(with-sc3
|
|
(lambda (fd)
|
|
(send fd m)))))
|
|
|
|
(define async-to
|
|
(lambda (m)
|
|
(with-sc3
|
|
(lambda (fd)
|
|
(async fd m)))))
|
|
|
|
(send-to (s-new1 "c" 1001 1 1 "k" 10))
|
|
|
|
(send-to (n-set1 1001 "k" 11))
|
|
(send-to (n-set1 1001 "t" 0))
|
|
(send-to (n-set1 1001 "t" 1))
|
|
|
|
(send-to (n-set1 1001 "k" 12))
|
|
(send-to (n-set1 1001 "t" 0))
|
|
(send-to (n-set1 1001 "t" 1))
|
|
|
|
(async-to (b-zero 12))
|
|
|
|
(for-each
|
|
(lambda (n)
|
|
(send-to (b-set1 12 (+ (* 20 n) 10) 1)))
|
|
(enum-from-to 0 39))
|
|
|
|
(send-to (n-set1 1001 "t" 0))
|
|
(send-to (n-set1 1001 "t" 1))}
|
|
|
|
With soundfile.
|
|
|
|
(async-to (b-alloc-read 10 "/home/rohan/audio/metal.wav" 0 0))
|
|
|
|
(let ((i (sound-in 0)))
|
|
(audition (out 0 (mul (convolution2 i 10 0 512) 0.5))))
|
|
|