pvsarp

pvsarp — Arpeggiate the spectral components of a streaming pv signal.

Description

This opcode arpeggiates spectral components, by amplifying one bin and attenuating all the others around it. Used with an LFO it will provide a spectral arpeggiator similar to Trevor Wishart's CDP program specarp.

Syntax

fsig pvsarp fsigin, kbin, kdepth, kgain

Performance

fsig -- output pv stream

fsigin -- input pv stream

kbin -- target bin, normalised 0 - 1 (0Hz - Nyquist).

kdepth -- depth of attenuation of surrounding bins

kgain -- gain boost applied to target bin

[Warning] Warning

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

Here is an example of the pvsarp opcode. It uses the file pvsarp.csd

Example 651. Example of the pvsarp 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 pvsarp.wav -W ;;; for file output any platform
</CsOptions>
<CsInstruments>

; Initialize the global variables.
sr = 44100
ksmps = 100
nchnls = 1
0dbfs = 1

instr 1
asig  in                                 ; get the signal in
idepth = p4

fsig  pvsanal   asig, 1024, 256, 1024, 1 ; analyse it
kbin  oscili   0.1, 0.5, 1               ; ftable 1 in the 0-1 range
ftps  pvsarp   fsig, kbin+0.01, idepth, 2   ; arpeggiate it (range 220.5 - 2425.5)
atps  pvsynth  ftps                      ; synthesise it

       out atps
endin


</CsInstruments>
<CsScore>
f 1 0 4096 10 1 ;sine wave

i 1 0 10 0.9
i 1 + 10 0.5
e


</CsScore>
</CsoundSynthesizer>


Here is another example of the pvsarp opcode. It uses the file pvsarp2.csd

Example 652. Example of the pvsarp 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
-odac    ;;;RT audio I/O
; For Non-realtime ouput leave only the line below:
; -o pvsarp2.wav -W ;;; for file output any platform
</CsOptions>
<CsInstruments>

sr = 44100
ksmps = 16
nchnls = 1
0dbfs = 1

;; example written by joachim heintz 2009

instr 1
ifftsize	=		1024
ioverlap	=		ifftsize / 4
iwinsize	=		ifftsize
iwinshape	=		1; von-Hann window
Sfile1		=		"fox.wav"
ain1		soundin	Sfile1
fftin		pvsanal	ain1, ifftsize, ioverlap, iwinsize, iwinshape
  ;make 3 independently moving accentuations in the spectrum
kbin1		linseg		0.05, p3/2, .05, p3/2, .05
farp1		pvsarp		fftin, kbin1, .9, 10
kbin2		linseg		0.075, p3/2, .1, p3/2, .075
farp2		pvsarp		fftin, kbin2, .9, 10
kbin3		linseg		0.02, p3/2, .03, p3/2, .04
farp3		pvsarp		fftin, kbin3, .9, 10
  ;resynthesize and add them
aout1		pvsynth	farp1
aout2		pvsynth	farp2
aout3		pvsynth	farp3
aout		=		aout1*.3 + aout2*.3 + aout3*.3
		out		aout
endin

</CsInstruments>
<CsScore>
i 1 0 3 
e
</CsScore>
</CsoundSynthesizer>


See Also

pvsanal, pvsynth, pvsadsyn

Credits

Author: Victor Lazzarini
April 2005

New plugin in version 5

April 2005.