scale(1) 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



Barry Vercoe
MIT Media Lab


Dan Ellis
MIT Media Lab,