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<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 opcode_example.wav -W ;;; for file output any platform </CsOptions> <CsInstruments> ; Required settings for WebAudio: sr = 48000 ksmps = 128 nchnls = 2 nchnls_i = 1 ; sr = 44100 ; ksmps = 32 ; nchnls = 2 0dbfs = 1 /* example opcode 1: simple oscillator */ opcode Oscillator, a, kk kamp, kcps xin ; read input parameters a1 vco2 kamp, kcps ; sawtooth oscillator xout a1 ; write output endop /* example opcode 2: lowpass filter with local ksmps */ opcode Lowpass, a, akk setksmps 1 ; need ; sr= kr ain, ka1, ka2 xin ; read input parameters aout init 0 ; initialize output aout = ain*ka1 + aout*ka2 ; simple tone-like filter xout aout ; write output endop /* example opcode 3: recursive call */ opcode RecursiveLowpass, a, akkpp ain, ka1, ka2, idep, icnt xin ; read input parameters if (icnt >= idep) goto skip1 ; check if max depth reached ain RecursiveLowpass ain, ka1, ka2, idep, icnt + 1 skip1: aout Lowpass ain, ka1, ka2 ; call filter xout aout ; write output endop /* example opcode 4: de-click envelope */ opcode DeClick, a, a ain xin aenv linseg 0, 0.02, 1, p3 - 0.05, 1, 0.02, 0, 0.01, 0 xout ain * aenv ; apply envelope and write output endop /* instr 1 uses the example opcodes */ instr 1 kamp = .7 ; amplitude kcps expon 50, p3, 500 ; pitch a1 Oscillator kamp, kcps ; call oscillator kflt linseg 0.4, 1.5, 0.4, 1, 0.8, 1.5, 0.8 ; filter envelope a1 RecursiveLowpass a1, kflt, 1 - kflt, 10 ; 10th order lowpass a1 DeClick a1 outs a1, a1 endin </CsInstruments> <CsScore> i 1 0 4 e5 ;extra second before quitting </CsScore> </CsoundSynthesizer>