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).
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.
Verification Link: Engine
Also a Traffic An added benefit of the verification link is that licensors, or the companies who do their hosting, can use them to draw traffic to their websites.
Example:
Ravi is an amateur photographer. He hosts his photos at SNAP, a website devoted to photography. Each time Ravi uploads his photos to the SNAP website, the SNAP software offers Ravi an opportunity to use Creative Commons licenses, and the tools to embed his webpage on SNAP with the appropriate RDF. Next, SNAP's software automatically inserts the verification link into his photo files' copyright fields.
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).