downsamp — Modify a signal by down-sampling.
iwlen (optional) -- window length in samples over which the audio signal is averaged to determine a downsampled value. Maximum length is ksmps; 0 and 1 imply no window averaging. The default value is 0.
downsamp converts an audio signal to a control signal by downsampling. It produces one kval for each audio control period. The optional window invokes a simple averaging process to suppress foldover.
Here is an example of the downsamp opcode. It uses the file downsamp.csd.
Example 246. Example of the downsamp 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 downsamp.wav -W ;;; for file output any platform </CsOptions> <CsInstruments> sr = 44100 ksmps = 32 nchnls = 2 0dbfs = 1 instr 1 ifrq = cpspch(p4) ain diskin2 "beats.wav", 1 aenv follow ain, .001 ;take the amplitude every 1/1000th of a second alow tone aenv, 25 ;lowpass-filter (25 Hz) for a clean signal kenv downsamp alow asig pluck kenv, ifrq, 15, 0, 1 outs asig, asig endin </CsInstruments> <CsScore> i 1 0 2 9 i 1 + . 7 i 1 + . 5 e </CsScore> </CsoundSynthesizer>