noise — A white noise generator with an IIR lowpass filter.
ioffset -- the delay before the first impulse. If it is negative, the value is taken as the number of samples, otherwise it is in seconds. Default is zero.
xamp -- amplitude of final output
kbeta -- beta of the lowpass filter. Should be in the range of 0 to 1.
The filter equation is:
y_n = sqrt(1-beta^2) * x_n + beta Y_(n-1)
where x_n is white noise.
Here is an example of the noise opcode. It uses the file noise.csd.
Example 243. Example of the noise 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 ; Audio out Audio in No messages -odac -iadc -d ;;;RT audio I/O ; For Non-realtime ouput leave only the line below: ; -o noise.wav -W ;;; for file output any platform </CsOptions> <CsInstruments> ; Initialize the global variables. sr = 44100 kr = 4410 ksmps = 10 nchnls = 1 ; Instrument #1. instr 1 kamp = 30000 ; Change the beta value linearly from 0 to 1. kbeta line 0, p3, 1 a1 noise kamp, kbeta out a1 endin </CsInstruments> <CsScore> ; Play Instrument #1 for one second. i 1 0 1 e </CsScore> </CsoundSynthesizer>