PUIDs (Portable Unique IDentifier) are the IDs used in the proprietary MusicDNS AudioFingerprinting system which was initially operated by MusicIP, later AmpliFIND and even later sold on to Gracenote who are expected to discontinue the public service.
MusicBrainz started to use these IDs in March 2006 and they were implemented in Picard 0.7.0 released in July 2006. As of June 2011, they are being phased out in favor of open source solutions.
- Several blogposts on the MusicBrainz Blog by RobertKaye:
- March 12, 2006 New fingerprinting technology available now!
- March 13, 2006 New fingerprinting questions answered
- March 28, 2006 Picard: Common questions answered and
- March 30, 2006 PUIDs: WTF?
- June 23, 2011 The EchoNest releases Echoprints: The open source fingerprint era has begun