The basics:
- Beforehand, Shazam fingerprints a comprehensive catalog of music, and stores the fingerprints in a database.
- A user “tags” a song they hear, which fingerprints a 10 second sample of audio.
- The Shazam app uploads the fingerprint to Shazam’s service, which runs a search for a matching fingerprint in their database.
- If a match is found, the song info is returned to the user, otherwise an error is returned.
More details at How Shazam Works To Identify (Nearly) Every Song You Throw At It including this fingerprint example
–jeroen
via: How Shazam Works To Identify (Nearly) Every Song You Throw At It.