Sound eXchange
the Swiss Army knife of sound processing programs allows command line manipulation and generation of audio files.
Audio Analysis
Find out information about an audio file
sox -V orig.wav -e stat
Audio Synthesis
Produce a 3 second, 48kHz, audio file containing a sine-wave swept from 300 to 3300 Hz.
sox -n output.wav synth 3 sine 300-3300
Produce a constant 8KHz 3 second tone.
sox -r 8000 -n output.wav synth 3 sine 300-3300
Cascade two synth effects simultaneously, to create a more complex waveform:
play -n synth 0.5 sine 200-500 synth 0.5 sine fmod 700-100
Create a 1KHz Tone, 1/2 second long, very slightly attenuated
sox -n loud.wav synth 0.5 sin 1000 gain -1
Create a 1KHz Tone, 200msec long, significantly attenuated
sox -n quiet.wav synth 0.2 sin 1000 gain -20
Play the Digit "7" DTMF Tone for 0.5 seconds
play -n synth 0.5 sine 852 sine 1209 channels 1
Create a file of the Digit "7" DTMF Tone
sox -n 7.wav synth 0.5 sine 852 sine 1209 channels 1
Play a DTMF "Dial Tone" for 5 seconds
play -n synth 5 sine 350 sine 440 channels 1
Audio Manipulation
Play two wav files, one after the other, repeated 5 times
play loud.wav quiet3.wav repeat 5
Append one file to another file
sox file1.wav file2.wav outputfile.wav
Take a file and repeat it 20 times into an output file
sox input.wav longfile.wav repeat 20
Convert PCM file to a wav file
sox -t .ul -r 8000 -c 1 -b 8 -U blah.PCMU -t wav -r 8000 -c 1 -b 8 -U file.wav
Convert a two channel wav file to a single channel PCM file
For FREESWITCH moh files
- Wave format is used for moh files
- moh files needs to be converted to the codecs required:
- pcma, pcmu
- 8 bit Sample Size
- 8000 kHz Sample Rate
- 1 channel (mono)
- files need to be named: moh_codec.wav
- e.g. moh_pcmu.wav, moh_pcma.wav
- files need to fit to the limited memory of the phones!
Convert wav file to PCMU file for use with freeswitch moh
sox -S -t wav -c 2 -2 -r 44100 orig.wav -t wav -c 1 -1 -r 8000 -U moh_pcmu.wav
Convert wave file to PCMA file for use with freeswitch moh
sox -S -t wav -c 2 -2 -r 44100 orig.wav -t wav -c 1 -1 -r 8000 -A moh_pcma.wav