filepeak

filepeak — Returns the peak absolute value of a sound file.

Description

Returns the peak absolute value of a sound file.

Syntax

ir filepeak ifilcod [, ichnl]

Initialization

ifilcod -- sound file to be queried

ichnl (optional, default=0) -- channel to be used in calculating the peak value. Default is 0.

  • ichnl = 0 returns peak value of all channels

  • ichnl > 0 returns peak value of ichnl

Performance

filepeak returns the peak absolute value of the sound file ifilcod. Currently, filepeak supports only AIFF-C float files.

Examples

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

Example 129. Example of the filepeak opcode.

See the sections Real-time Audio and Command Line Flags for more information on using command line flags.
<CsoundSynthesizer>
<CsOptions>
; 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 filepeak.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
  ; Print out the peak absolute value of the
  ; audio file "mary.wav".
  ipeak filepeak "mary.wav"
  print ipeak
endin


</CsInstruments>
<CsScore>

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


</CsScore>
</CsoundSynthesizer>

          

The peak absolute value of the audio file “mary.wav” is 0.306902. So filepeak's output should include a line like this:

instr 1:  ipeak = 0.307
      

See Also

filelen, filenchnls, filesr

Credits

Author: Matt Ingalls
July 1999

Example written by Kevin Conder.

New in Csound version 3.57