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<CsoundSynthesizer> <CsOptions> ; Select audio/midi flags here according to platform ; Audio out Audio in No display -odac -iadc -d ;;;RT audio I/O </CsOptions> <CsInstruments> ; Required settings for WebAudio: sr = 48000 ksmps = 128 nchnls = 2 nchnls_i = 1 sr = 44100 ksmps = 10 ; nchnls = 1 ; Example by Jonathan Murphy 2007 ;;; reset amplitude range 0dbfs = 1 ;;; set the base colour for the panel FLcolor 100, 0, 200 ;;; define the panel FLpanel "FLexecButton", 250, 100, 0, 0 ;;; sliders to control time stretch and pitch gkstr, gistretch FLslider "Time", 0.5, 1.5, 0, 6, -1, 10, 60, 150, 20 gkpch, gipitch FLslider "Pitch", 0.5, 1.5, 0, 6, -1, 10, 60, 200, 20 ;;; set FLexecButton colour FLcolor 255, 255, 0 ;;; when this button is pressed, fourier analysis is performed on the file ;;; "beats.wav", producing the analysis file "beats.pvx" gipvoc FLexecButton "csound -U pvanal beats.wav beats.pvx", 60, 20, 20, 20 ;;; set FLexecButton text FLsetText "PVOC", gipvoc ;;; when this button is pressed, instr 10000 is called, exiting ;;; Csound immediately ;;; cancel previous colour FLcolor -1 ;;; set colour for kill button FLcolor 255, 0, 0 gkkill, gikill FLbutton "X", 1, 1, 1, 20, 20, 100, 20, 0, 10000, 0, 0.1 ;;; cancel previous colour FLcolor -1 ;;; set colour for play/stop and pause buttons FLcolor 0, 200, 0 ;;; pause and play/stop buttons gkpause, gipause FLbutton "@||", 1, 0, 2, 40, 20, 20, 60, -1 gkplay, giplay FLbutton "@|>", 1, 0, 2, 40, 20, 80, 60, -1 ;;; end the panel FLpanelEnd ;;; set initial values for time stretch and pitch FLsetVal_i 1, gistretch FLsetVal_i 1, gipitch ;;; run the panel FLrun instr 1 ; trigger play/stop ;;; is the play/stop button on or off? ;;; either way we need to trigger something, ;;; so we can't just use the value of gkplay kon trigger gkplay, 0, 0 koff trigger gkplay, 1, 1 ;;; if on, start instr 2 schedkwhen kon, -1, -1, 2, 0, -1 ;;; if off, stop instr 2 schedkwhen koff, -1, -1, -2, 0, -1 endin instr 2 ;;; paused or playing? if (gkpause == 1) kgoto pause kgoto start pause: ;;; if the pause button is on, skip sound production kgoto end start: ;;; get the length of the analysis file in seconds ilen filelen "beats.pvx" ;;; determine base frequency of playback icps = 1/ilen ;;; create a table over the length of the file itpt ftgen 0, 0, 513, -7, 0, 512, ilen ;;; phasor for time control kphs phasor icps * gkstr ;;; use phasor as index into table kndx = kphs * 512 ;;; read table ktpt tablei kndx, itpt ;;; use value from table as time pointer into file fsig1 pvsfread ktpt, "beats.pvx" ;;; change playback pitch fsig2 pvscale fsig1, gkpch ;;; resynthesize aout pvsynth fsig2 ;;; envelope to avoid clicks and clipping aenv linsegr 0, 0.3, 0.75, 0.1, 0 aout = aout * aenv out aout end: endin instr 10000 ; kill exitnow endin </CsInstruments> <CsScore> i1 0 10000 e </CsScore> </CsoundSynthesizer>