GnuDB

GnuDB, short for 'Global Network Universal Database,' stands as a distinct entity from freedb, marking its significance as one of the largest CD databases leveraging the CDDB.

To address some weaknesses in the old discid used in the CDDB protocol, we introduced a new ID called gnucdid. The gnucdid retains the 8-character hex format but is unique to each set of metadata. Queries are performed using the CD layout as usual. The response from gnudb will include one or more gnucdids, sorted by the closest matching layout first. Currently, there are over 9,000,000 GnuDB CD layouts with corresponding metadata. Categories have been removed, and we always return the category "data" to ensure compatibility with older programs.

Recently, GnuDB expanded the functionality of the CDDB protocol by introducing a search feature. This allows users to manually search the database for CDs based on artist, album, or track information when no match is initially found. A separate cover art search feature has also been added, and the XMCD response is now extended with a # Artid: field where applicable.