# sox
# Sound eXchange: play, record and convert audio files.
# Audio formats are identified by the extension.

# Merge two audio files into one:
sox -m ${input_audiofile1} ${input_audiofile2} ${output_audiofile}

# Trim an audio file to the specified times:
sox ${input_audiofile} ${output_audiofile} trim ${start} ${end}

# Normalize an audio file
# (adjust volume to the maximum peak level, without clipping):
sox --norm ${input_audiofile} ${output_audiofile}

# Reverse and save an audio file:
sox ${input_audiofile} ${output_audiofile} reverse

# Print statistical data of an audio file:
sox ${input_audiofile} -n stat

# Increase the volume of an audio file by 2x:
sox -v 2.0 ${input_audiofile} ${output_audiofile}

# Changing sample rate of a file
sox ${input_file} -r 16000 ${output_file}

# Changing the Number of Channels
# For example: convert mono audio files to stereo
sox ${mono_wav} -c 2 ${stereo_wav}

# Generate Different Types of Sounds
# ${len} - length of audio to synthesize, hh:mm:ss.frac
# ${freq} - frequencies at the beginning/end of synthesis in Hz
# ${type} is one of sine, square, triangle, sawtooth, trapezium, exp,
#   [white]noise, pinknoise, brown-noise
# sox -n synth ${len} ${type} ${freq}
sox -r 8000 -n output.wav synth 3 sine 300-3300

# Speed up the Sound in an Audio File
sox input.wav output.wav speed 2.0