Steganography

Convert video to music file

ffmpeg -i file.mp4 sound.mp3

Extract DTMF (Dual tone multi frequency) from sound file

Import sound file to http://dialabc.com/sound/detect/
Needs to be WAV, RIFF, PCM, or Sun/NeXt

Resources

Sherlock: https://github.com/sherlock-project/sherlock