readk2 — Periodically reads two orchestra control-signal values from an external file.


Periodically reads two orchestra control-signal values from an external file.


kr1, kr2 readk2 ifilname, iformat, iprd


ifilname -- an integer N denoting a file named "readk.N" or a character string (in double quotes, spaces permitted) denoting the external file name. For a string, it may either be a full path name with directory specified or a simple filename. In the later case, the file is sought first in the current directory, then in SSDIR, and finally in SFDIR.

iformat -- specifies the input data format:

  • 1 = 8-bit signed integers (char)

  • 4 = 16-bit short integers

  • 5 = 32-bit long integers

  • 6 = 32-bit floats

  • 7 = ASCII long integers (plain text)

  • 8 = ASCII floats (plain text)

Note that A-law and U-law formats are not available, and that all formats except the last two are binary. The input file should be a "raw", headerless data file.

iprd -- the rate (period) in seconds, rounded to the nearest orchestra control period, at which the signals are read from the input file. A value of 0 implies one control period (the enforced minimum), which will read new values at the orchestra control rate. Longer periods will cause the same values to repeat for more than one control period.


kr1, kr2 -- output of the signals read from ifilname.

This opcode allows two generated control signal values to be read from a named external file. The file should contain no header information but it should contain a regularly sampled time series of control values. For binary formats, the individual samples of each signal are interleaved. For ASCII text formats, the values are assumed to be separated by at least one whitespace character. The two "channels" in a sample frame may be on the same line or separated by newline characters, it does not matter. There may be any number of readk2 opcodes in an instrument or orchestra and they may read from the same or different files.


Here is an example of the readk2 opcode. It uses the file readk2.csd.

Example 907. Example of the readk2 opcode.

See the sections Real-time Audio and Command Line Flags for more information on using command line flags.

; 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 readk2.wav -W ;;; for file output any platform

sr = 44100
ksmps = 32
nchnls = 2
0dbfs  = 1

giSine ftgen 0, 0, 2^10, 10, 1

instr 1 ;writes two control signals to a file
kfreq     randh     100, 1, 2, 1, 500 ;generates one random number between 400 and 600 per second
kdb       randh     12, 1, 2, 1, -12 ;amplitudes in dB between -24 and 0
          dumpk2    kfreq, kdb, "dumpk2.txt", 8, 1 ;writes the control signals
          prints    "WRITING:\n"
          printks   "kfreq = %f, kdb = %f\n", 1, kfreq, kdb  ;prints them

instr 2 ;reads the file written by instr 1
kf,kdb    readk2    "dumpk2.txt", 8, 1
          prints    "READING:\n"
          printks   "kfreq = %f, kdb = %f\n", 1, kf, kdb  ;prints again
kdb       lineto    kdb, .1 ;smoothing amp transition
aout      poscil    ampdb(kdb), kf, giSine
          outs      aout, aout

i 1 0 5
i 2 5 5

The output should include lines like these:

kfreq = 429.202551, kdb = -20.495694
kfreq = 429.202551, kdb = -20.495694
kfreq = 407.275258, kdb = -23.123776
kfreq = 475.264472, kdb = -9.300846
kfreq = 569.979181, kdb = -7.315527
kfreq = 440.103457, kdb = -0.058331

kfreq = 429.202600, kdb = -20.495700
kfreq = 429.202600, kdb = -20.495700
kfreq = 407.275300, kdb = -23.123800
kfreq = 475.264500, kdb = -9.300800
kfreq = 569.979200, kdb = -7.315500
kfreq = 440.103500, kdb = -0.058300

See also

File Input and Output


By: John ffitch and Barry L. Vercoe

1999 or earlier