Exploring Open Data: Public Domain Works in Wikidata
The Current State of Open Data on Public Domain Works
A public domain work is essentially any creative material that is not protected by copyright law. The internet has made the content of these works wonderfully findable and accessible by the general public. Surprisingly, retrieving the metadata on these works is an entirely different story, perhaps precisely because there is no IP. Public domain art archives have made the biggest strides; the Metropolitan Museum of Art and the Art Institute of Chicago have been pioneers in creating rich knowledge structures for their archives and making that data open via robust APIs. Several art institutions such as Rijksmuseum in the Netherlands, Harvard Art Museums, and the Smithsonian are not far behind. As such, a user or agent wanting to query and build public art knowledge graphs can expect to do so without too much friction. Unfortunately, outside of art, this is much less the case. In the area of literature, Project Gutenberg and Open Library, excellent sources for reading public domain text, do open up their metadata, but queryability, schemas, and comprehensiveness are lacking. Similarly, with public domain music, music can be readily accessed through various internet archives and music scores through the International Music Score Library Project, but complete and accurate metadata is difficult to retrieve. Fortunately, MusicBrainz, an open encyclopedia for music data, is facilitating the ongoing curation and access for much of this information. Public domain film metadata does not appear to be widely available in clean, open, queryable formats, but as exponentially more films enter the public domain in the coming decades, the hope is this will change.