ftchnls — Returns the number of channels in a stored function table.


Returns the number of channels in a stored function table.


ftchnls(x) (init-rate args only)


Returns the number of channels of a GEN01 table, determined from the header of the original file. If the original file has no header or the table was not created by these GEN01, ftchnls returns -1.


Here is an example of the ftchnls opcode. It uses the file ftchnls.csd, and mary.wav.

Example 169. Example of the ftchnls 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 ftchnls.wav -W ;;; for file output any platform

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

; Instrument #1.
instr 1
  ; Print out the number of channels in Table #1.
  ichnls = ftchnls(1)
  print ichnls


; Table #1: Use an audio file, Csound will determine its size.
f 1 0 0 1 "mary.wav" 0 0 0

; Play Instrument #1 for 1 second.
i 1 0 1


Since the audio file “mary.wav” is monophonic (1 channel), its output should include a line like this:

instr 1:  ichnls = 1.000

See Also

ftlen, ftlptim, ftsr, nsamp


Author: Chris McCormick
Perth, Australia
December 2001

Example written by Kevin Conder.