It sounds like Acoustical Song Recognition.
Audio Waveform Recognition (audio fingerprints)
Audio Waveform Recognition Technology
Using audio waveform fingerprint technology, MusicID can identify individual songs or albums in a user's collection regardless of source, format or tag information.
Consumers simply hold up their phone anywhere the music is playing?in a bar, at a party or on the radio. Then a short clip of the music, from any section of the song, is matched to Gracenote?s global database of audio fingerprints and music information. Once identified, Gracenote Link? can be used to automatically connect the user to related content for hearing, viewing and purchase. Music fans get fast access to ringtones, full tracks, videos and all the content that makes mobile music fun.
CDDB:
http://www.gracenote.com/gn_products/music_id.html