Difference between revisions of "Embedded Metadata"

Creative Commons licenses are attached to Web pages. But we also want our licenses to be useful for materials distributed in file formats around the Net. The protocol described here works for many filetypes.

If your software does not transparently support embedding CC license metadata (you should only have to select a license), do not attempt to do it yourself (it will be a frustrating experience).

Embedding the metadata

Let's say Anita wants to license her song, "Volcano Love," with a Creative Commons license, and release it as an MP3. Here's what she'd do:

First, Anita would put a "Some Rights Reserved" button on the site where her song could be downloaded — along with a link to a license, some RDF metadata, and an assertion about the copyright status of the work. Nothing new here: this is what Creative Commons licensors do now.

With file embedding, though, this page will now serve the added function of verification. Here's how: Anita would insert the URL to that webpage in the copyright field of the MP3 file, along with a short, plain description of the work's license status. We call this the license verification link because it points back to a page that Anita herself controls.

Next, imagine Anita puts the MP3 on a file-sharing network. A user comes across her MP3 and can follow the verification link to Anita's page. In the future, we hope that file-sharing networks, media players, and other applications will build tools that read the verification link automatically and inform users of the copyright assertions like Anita's.

The advantage of the verification link

Embedding this kind of "verification link" in MP3s, as opposed to merely the license metadata, is a measure of protection for artists against the incorrect or fraudulent labeling and sharing of their work.

Ravi circulates the photos among his schoolmates, whose photo-viewing software reads the copyright fields and takes them to the SNAP website, where they can see Ravi's whole catalog of photography and links to other SNAP services.

Technical Explanation

See Nonweb Tagging, and for specific formats, see MP3 and XMP (PDF, JPEG, video).