pvsfilter
pvsfilter — Multiply amplitudes of a pvoc stream by those of a second pvoc stream, with dynamic scaling.
Description
Multiply amplitudes of a pvoc stream by those of a second pvoc stream, with dynamic scaling.
Performance
fsig -- output pv stream
fsigin -- input pv stream.
fsigfil -- filtering pvoc stream.
kdepth -- controls the depth of filtering of fsigin by fsigfil .
igain -- amplitude scaling (optional, defaults to 1).
Here the input pvoc stream amplitudes are modified by the filtering stream, keeping its frequencies intact. As usual, both signals have to be in the same format.
![[Warning]](images/warning.png)
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Warning |
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It is unsafe to use the same f-variable for both input and output of pvs opcodes. Using the same one might lead to undefined behavior on some opcodes. Use a different one on the left and right sides of the opcode. |
Examples
Example 828. Example
kfreq expon 500, p3, 4000 ; 3-octave sweep kdepth linseg 1, p3/2, 0.5, p3/2, 1 ; varying filter depth asig in ; input afil oscili 1, kfreq, 1 ; filter t-domain signal fim pvsanal asig,1024,256,1024,0 ; pvoc analysis fil pvsanal afil,1024,256,1024,0 fou pvsfilter fim, fil, kdepth ; filter signal aout pvsynth fou ; pvoc synthesis
In the example above the filter curve will depend on the spectral envelope of afil; in the simple case of a sinusoid, it will be equivalent to a narrowband band-pass filter.
Here is an example of the use of the pvsfilter opcode. Play pvsfilter.csd
Example 829. Example of the pvsfilter 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 pvsfilter.wav -W ;;; for file output any platform </CsOptions> <CsInstruments> sr = 44100 ksmps = 32 nchnls = 2 0dbfs = 1 ;; example written by joachim heintz 2009 giSine ftgen 0, 0, 4096, 10, 1 giBell ftgen 0, 0, 4096, 9, .56, 1, 0, .57, .67, 0, .92, 1.8, 0, .93, 1.8, 0, 1.19, 2.67, 0, 1.7, 1.67, 0, 2, 1.46, 0, 2.74, 1.33, 0, 3, 1.33, 0, 3.76, 1, 0, 4.07, 1.33, 0; bell-like (after Risset) instr 1 ipermut = p4 ; 1 = change order of soundfiles ifftsize = 1024 ioverlap = ifftsize / 4 iwinsize = ifftsize iwinshape = 1 ; von-Hann window Sfile1 = "fox.wav" ain1 soundin Sfile1 kfreq randomi 200, 300, 3 ain2 oscili .2, kfreq, giBell ;ain2 oscili .2, kfreq, giSine; try also this fftin1 pvsanal ain1, ifftsize, ioverlap, iwinsize, iwinshape; fft-analysis of file 1 fftin2 pvsanal ain2, ifftsize, ioverlap, iwinsize, iwinshape; fft-analysis of file 2 if ipermut == 1 then fcross pvsfilter fftin2, fftin1, 1 else fcross pvsfilter fftin1, fftin2, 1 endif aout pvsynth fcross outs aout * 30, aout * 30 endin </CsInstruments> <CsScore> i 1 0 2.757 0; frequencies from fox.wav, amplitudes multiplied by amplitudes of giBell i 1 3 2.757 1; frequencies from giBell, amplitudes multiplied by amplitudes of fox.wav e </CsScore> </CsoundSynthesizer>