Audio manipulation with SoX

SoX (Sound eXchange) calls itself “the Swiss Army knife of sound processing programs” and offers, apart from standard audio format and sample rate conversion, a basic set of effects (e.g. pitch shifting, reverb, low pass filtering, flanger, etc). It’s available for Linux (search for ‘sox’ in your package manager), Mac OS X and Windows.

Minimal conversion example

sox input.mp3 output.wav

Convert to mono (two possibilities: by specifying output format

or with the ‘channels’ effect.

sox input.mp3 -c 1 output.wav sox input.mp3 output.wav channels 1

Change sample rate (again two possibilities)

sox input.mp3 -r 8000 output.wav sox input.mp3 output.wav rate 8000

Newer versions of SoX also support

sox input.mp3 output.wav rate 8k

Trim a fragment of 30 seconds at an offset of 60 seconds

with the ‘trim’ effect

sox input.mp3 output.wav trim 60 30

All together now (trimmed fragment in mono, 22.05 Hz sample rate)

sox input.mp3 output.wav trim 60 30 channels 1 rate 22050

source code