scale — Scale the amplitude of a sound file.


Takes a sound file and scales it by applying a gain, either constant or variable. The scale can be specified as a multiplier, a maximum or a percentage of 0db.


scale [OPTIONS ... ] infile



  • -A = Generate an AIFF outout file.

  • -W = Generate an WAV outout file.

  • -h = Generate an outout file with no header.

  • -c = Generate 8-bit signed_char sound samples.

  • -a = Generate alaw sound samples.

  • -u = Generate ulaw sound samples.

  • -s = Generate short integer sound samples.

  • -l = Generate long (32 bit) integer sound samples.

  • -f = Generate floating point samples.

  • -F arg = Specifies the gain to be applied. If arg is a floating point number that gain is applied uniformly to the input. Alternatively it could be a file name which specifies a breakpoint file for varying the gain for different periods.

  • -M fpnum = Scales the input so the maximum absolute displacement is the value given.

  • -P fpnum = Scales the input so the maximum absolute displacement is the pencentage given of 0db.

  • -R = Continually rewrite the header while writing soundfile (WAV/AIFF).

  • -H integer = Show a "heart-beat" to indicate progress, in style 1, 2 or 3.

  • -N = Alert call (usually ringing the bell) when finished.

  • -o fname = output file name (default: test.wav)


    scale -s -W -F 0.96 -o out.wav sound.wav

This creates a new sound file with a constant gain of 0.96. It is particularly useful if the input file is in floating point format.


Author: John ffitch