readk — Periodically reads an orchestra control-signal value from an external file.


Periodically reads an orchestra control-signal value from a named external file in a specific format.


kres readk 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 is 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 unless interpolation is used.


kres -- output of the signal read from ifilname.

This opcode allows a generated control signal value 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 ASCII text formats, the values are assumed to be separated by at least one whitespace character. There may be any number of readk opcodes in an instrument or orchestra and they may read from the same or different files.


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

Example 391. Example of the readk 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
; Audio out   Audio in
-odac           -iadc    ;;;RT audio I/O
; For Non-realtime ouput leave only the line below:
; -o readk.wav -W ;;; for file output any platform

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

0dbfs = 1
; By Andres Cabrera 2008

instr 1
; Read a number from the file every 0.5 seconds
  kfibo readk "fibonacci.txt", 7, 0.5
  kpitchclass = 8 +  ((kfibo % 12)/100)
  printk2 kpitchclass
  kcps = cpspch( kpitchclass )
  printk2 kcps
  a1 oscil 0.5, kcps, 1
  out a1

f 1 0 1024 10 1
i 1 0 10


See Also

dumpk, dumpk2, dumpk3, dumpk4, readk2, readk3, readk4


By: John ffitch and Barry Vercoe

1999 or earlier