Editing MusicBrainz (section)

==Fingerprinting==
[[File:MusicBrainz Picard 2.7 screenshot.png|thumb|Screenshot of MusicBrainz Picard]]
In addition to collecting metadata about music, MusicBrainz also allows users to match recordings by their [[acoustic fingerprint]]. A separate application, such as MusicBrainz Picard, is used to do this.

===Proprietary services===
In 2000, MusicBrainz started using ''Relatable's'' patented TRM (a [[recursive acronym]] for TRM Recognizes Music) for acoustic fingerprint matching. The popularity of this feature drew in a large user base into the platform, enabling the database to expand rapidly. By 2005, TRM was experiencing difficulties in handling the sheer volume of data, as the number of tracks stored in the database had surpassed one million. This issue was resolved in May 2006 when MusicBrainz partnered with MusicIP (now [[AmpliFIND]]), replacing TRM with MusicDNS.<ref name="musicdns_announcement">{{cite press release|title=New fingerprinting technology available now!|date=2006-03-12|publisher=MusicBrainz community blog|url=http://blog.musicbrainz.org/archives/2006/03/new_fingerprint.html|access-date=2006-08-03|archive-url=https://web.archive.org/web/20080807161630/http://blog.musicbrainz.org/archives/2006/03/new_fingerprint.html|archive-date=2008-08-07|url-status=live}}</ref> TRMs were phased out and replaced by MusicDNS in November 2008.

In October 2009 MusicIP was acquired by [[AmpliFIND]].<ref>[http://www.amplifindmusicservices.com/news/press/amplified-music-aims-to-liberate-your-music.php AmpliFIND Music Services: News<!-- Bot generated title -->] {{webarchive|url=https://web.archive.org/web/20130921055804/http://www.amplifindmusicservices.com/news/press/amplified-music-aims-to-liberate-your-music.php|date=2013-09-21}}</ref>

===AcoustID and Chromaprint===
Since the future of the free identification service was uncertain, a replacement for it was sought. The Chromaprint acoustic fingerprinting algorithm, the basis for [[AcoustID]] identification service, was started in February 2010 by a long-time MusicBrainz contributor Lukáš Lalinský.<ref>{{cite web|url=http://oxygene.sk/2010/07/introducing-chromaprint|title=Introducing Chromaprint – Lukáš Lalinský|publisher=Oxygene.sk|date=2010-07-24|access-date=2018-04-10|archive-url=https://web.archive.org/web/20181010193315/https://oxygene.sk/2010/07/introducing-chromaprint|archive-date=2018-10-10|url-status=live}}</ref> While AcoustID and Chromaprint are not officially MusicBrainz projects, they are closely tied with each other and both are open source. Chromaprint works by analyzing the first two minutes of a track, detecting the strength for each of 12 [[pitch class]]es, storing these eight times per second. Additional post-processing is then applied to compress the fingerprint while retaining patterns.<ref>{{Cite journal|url=http://oxygene.sk/2011/01/how-does-chromaprint-work|title=How does Chromaprint work? – Lukáš Lalinský|journal=IEEE Transactions on Information Forensics and Security|volume=4|issue=4|pages=995–1004|doi=10.1109/TIFS.2009.2034452|date=2011-01-18|access-date=2018-04-10|last1=Jang|first1=Dalwon|last2=Yoo|first2=Chang D|last3=Lee|first3=Sunil|last4=Kim|first4=Sungwoong|last5=Kalker|first5=Ton|s2cid=1502596}}</ref> The AcoustID search server then searches from the database of fingerprints by similarity and returns the AcoustID identifier along with MusicBrainz recording identifiers, if known.