filenchnls — Returns the number of channels in a sound file.


Returns the number of channels in a sound file.


ir filenchnls ifilcod [, iallowraw]


ifilcod -- sound file to be queried

iallowraw -- (Optional) Allow raw sound files (default=1)


filenchnls returns the number of channels in the sound file ifilcod. filechnls can return the number of channels of convolve and PVOC files if the iallowraw flag is not zero (it is non-zero by default).


Here is an example of the filenchnls opcode. It uses the file filenchnls.csd, fox.wav, and drumsSlp.wav.

Example 300. Example of the filenchnls 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 filenchnls.wav -W ;;; for file output any platform

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

; by Menno Knevel 2022

instr 1 ; choose between mono or stereo file

ichn filenchnls  p4	            ; check number of channels
prints  "\nnumber of channels = %d\n\n", ichn

if (ichn == 1) then
    asig diskin2 p4, 1              ; mono signal	
    outs    asig, asig
    aL, aR diskin2 p4, 1            ; stereo signal
    outs    aL, aR



i 1 0 3 "fox.wav"	;mono signal
i 1 5 4 "drumsSlp.wav"	;stereo signal

The audio file fox.wav is monoaural (1 channel), while drumsSlp.wav is stereo (2 channels) So filenchnls's output should include lines like this:

number of channels = 1
number of channels = 2

See also

Sound File Queries


Author: Matt Ingalls
July 1999

New in Csound version 3.57