GRAIL: Database Linking Music Metadata Across Artist, Release, and Track

Linking information from multiple music databases is important for MIR because it provides a means to determine consistency of metadata between resources/services, which can help facilitate innovative product development and research. However, as yet, no open access tools exist that persistently link and validate metadata resources at the three main entities of music data: artist, release, and track. This paper introduces an open access resource which attempts to address the issue of linking information from multiple music databases. The General Recorded Audio Identity Linker (GRAIL - api.digitalmusiclab.org) is a music metadata ID-linking API that: i) connects International Standard Recording Codes (ISRCs) to music metadata IDs from services such as MusicBrainz, Spotify, and Last.FM; ii) provides these ID linkages as a publicly available resource; iii) confirms linkage accuracy using continuous metadata crawling from music-service APIs; and iv) derives consistency values (CV) for linkages by means of a set of quantifiable criteria. To date, more than 35M tracks, 8M releases, and 900K artists from 16 services have been ingested into GRAIL. We discuss the challenges faced in past attempts to link music metadata, the methods and rationale which we adopted in order to construct GRAIL and to ensure it remains updated with validated information.