Description

Generate control signal consisting of held segments delimited by two or more specified points. The entire envelope is looped at kfreq rate. Each parameter can be varied at k-rate.

Syntax

ksig lpshold kfreq, ktrig, ktime0, kvalue0  [, ktime1] [, kvalue1] \
      [, ktime2] [, kvalue2] [...]

Performance

ksig -- Output signal

kfreq -- Repeat rate in Hz or fraction of Hz

ktrig -- If non-zero, retriggers the envelope from start (see trigger opcode), before the envelope cycle is completed.

ktime0...ktimeN -- Times of points; expressed in fraction of a cycle

kvalue0...kvalueN -- Values of points

lpshold is similar to loopseg, but can generate only horizontal segments, i.e. holds values for each time interval placed between ktimeN and ktimeN+1. It can be useful, among other things, for melodic control, like old analog sequencers.

Examples

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

<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 lpshold.wav -W ;;; for file output any platform
</CsOptions>
<CsInstruments>

; Initialize the global variables.
sr = 44100
kr = 4410
ksmps = 10
nchnls = 1

; Instrument #1
instr 1
  kfreq line 1, p3, 20

  klp lpshold kfreq, 0, 0, 0, p3*0.25, 20000, p3*0.75, 0

  a1 oscil klp, 440, 1
  out a1
endin


</CsInstruments>
<CsScore>

; Table #1, a sine wave.
f 1 0 16384 10 1

; Play Instrument #1 for five seconds.
i 1 0 5
e


</CsScore>
</CsoundSynthesizer>

See Also

loopseg

Credits

Author: Gabriel Maldonado

New in Version 4.13