Audio Fingerprint

Audio fingerprints are identifiers for audio files based on the contained audio data.

MusicBrainz originally used Relatable's TRM exclusively as their only audio fingerprint technology, but due to various scalability and performance issues, and the fact that the server is closed-source and thus, not fixable, an alternative was required. MusicIPs PUID technology was chosen in March of 2006 as an efficient alternative.

PUIDs were first integrated into Picard 0.7, and have seen continuous support in the MusicBrainz Server.

Also see: How PUIDs Work and Future Proof Fingerprint.

Known Audio Fingerprinting Systems

Open Source Systems

• The fingerprint in Kurt Rosenfeld's FDMF.
• MusicURI, part of the Mpeg-7 Audio DB project.
• jHears is an acoustic fingerprinting framework based on FutureProofFingerPrint design by Geoff Schmidt (formerly of Tuneprint). jHears is developed by Juha Heljoranta.
• Acoustid is an open source project that aims to create a free database of audio fingerprints with mapping to the MusicBrainz metadata database and provide a web service for audio file identification using this database. Developed by Lukáš Lalinský
• AudioScout. Based on the pHash audio fingerprinting library, developed by the same authors. Uses the "Philips Robust Hashing" algorithm.
• OpenFP.
• [defunct] libFooID. An audio fingerprinting library used by, and developed for foosic.
• [defunct] Freetantrum. It seems to be a dead project (its home page was replaced with an advert for unrelated things in 2001), but it may be worth investigating and resurrecting the code they produced.

Partially Open-Source Systems

• AmpliFIND Music Services's PUID (formerly MusicIP/MusicMagic/Predixis)
  The PUID technology has been integrated into the MusicBrainz since March 2006 and into Picard since version 0.7.0 released in July 2007. See their patent application for details on the technology. The client-side audio fingerprinting library (libofa) is open-source.
• Last.fm. The client-side audio fingerprinting library (fplib) is open-source. Uses the "Computer Vision for Music Identification" algorithm.
• The Echo Nest. Originally a proprietary system, but the source code has been recently released on GitHub -- server, codegen
• [defunct] Relatable's TRM. The system MusicBrainz originally used. The use of TRM has since been removed from MusicBrainz. The client-side audio fingerprinting library was open source and integrated into libmusicbrainz.

Commercial Systems

• Audible Magic. This article compares business models for Philips & Audible Magic
• AudioID. Developed at the Fraunhofer Institute for Integrated Circuits IIS and the Fraunhofer Institute for Digital Media Technology IDMT, now provided by mufin GmbH.
• Shazam. Proprietary music fingerprinting system, currently offered directly to users over the telephone.
• Rovi Media Recognition Service (formelly AMG LASSO).
• Gracenote MusicID.
• Philips. One of the first scalable audio fingerprint algorithms. Described here and here.
• USC
• And possibly most ridiculously of all: The Song Tapper