gendyc

gendyc — Dynamic stochastic approach to waveform synthesis using cubic interpolation.

Description

Implementation with cubic interpolation of the Génération Dynamique Stochastique (GENDYN), a dynamic stochastic approach to waveform synthesis conceived by Iannis Xenakis.

Syntax

ares gendyc kamp, kampdist, kdurdist, kadpar, kddpar, kminfreq, kmaxfreq, \
            kampscl, kdurscl [, initcps] [, knum]
kres gendyc kamp, kampdist, kdurdist, kadpar, kddpar, kminfreq, kmaxfreq, \
            kampscl, kdurscl [, initcps] [, knum]

Initialization

initcps (optional, default=12) -- max number of control points.

Performance

kamp -- amplitude.

kampdist -- choice of probability distribution for the next perturbation of the amplitude of a control point. The valid distributions are:

  • 0 - LINEAR

  • 1 - CAUCHY

  • 2 - LOGIST

  • 3 - HYPERBCOS

  • 4 - ARCSINE

  • 5 - EXPON

  • 6 - SINUS (external k-rate signal)

If kampdist=6, the user can use an external k-rate signal through kadpar.

kdurdist -- choice of distribution for the perturbation of the current inter control point duration. See kampdist for the valid distributions. If kdurdist=6, the user can use an external k-rate signal through kddpar.

kadpar -- parameter for the kampdist distribution. Should be in the range of 0.0001 to 1.

kddpar -- parameter for the kdurdist distribution. Should be in the range of 0.0001 to 1.

kminfreq -- minimum allowed frequency of oscillation.

kmaxfreq -- maximum allowed frequency of oscillation.

kampscl -- multiplier for the distribution's delta value for amplitude (1.0 is full range).

kdurscl -- multiplier for the distribution's delta value for duration.

knum (optional, default=initcps) -- current number of utilized control points.

The waveform is generated by knum - 1 segments and is repeated in the time. The vertexes (control points) are moved according to a stochastic action and they are limited within the boundaries of a mirror formed by an amplitude barrier and a time barrier.

Examples

Here is an example of the gendyc opcode. It uses the file gendyc.csd.

Example 339. Example of the gendyc opcode.

See the sections Real-time Audio and Command Line Flags for more information on using command line flags.

<CsoundSynthesizer>
<CsOptions>
; Select audio/midi flags here according to platform
-odac     ;;;realtime audio out
;-iadc    ;;;uncomment -iadc if realtime audio input is needed too
; For Non-realtime ouput leave only the line below:
; -o oscil.wav -W ;;; for file output any platform
</CsOptions>
<CsInstruments>

sr = 44100
ksmps = 32
nchnls = 2
0dbfs  = 1

instr 1

aout gendyc 0.5, 1, 1, 1, 1, 220, 440, 0.5, 0.5
outs aout, aout

endin
</CsInstruments>
<CsScore>
i1 0 10
e
</CsScore>
</CsoundSynthesizer>


References

  1. Formalized Music (1992, Stuyvesant, NY: Pendragon Press), pp. 246 - 254, 289 - 322.

See Also

gendy gendyx

Credits

Based on Nick Collins's Gendy1 and Bhob Rainey's Gendy4 (SuperCollider)
Author: Tito Latini
January 2012

New in Csound version 5.16