Similar to the yahoo-media extension, c.f. Using media rss to syndicate and share media, there is a proposal for an atom media extension.
Some links:
One of the main differences is introducing <media:content> vs. extending <atom:link rel="enclosure">. To some extent this has the advantage of having a fall back to the basic <atom:link rel="enclosure"> is the extension isn't understood. On the other hand <media:content> is widely understood by parsers.
Quote from http://www.apparently.me.uk/22448.html, giving some motivation for a simplified namespace (compared to yahoo-media extension):
- MediaRSS uses extension elements exclusively, while AtomMedia extends the atom:link element. In particular, it extends standard Atom's link rel="enclosure" for compatibility with existing implementations.
- AtomMedia excludes the MediaRSS features that are not directly useful for the aggregation and activity stream use-cases. In particular, I did not include content ratings, regional exclusions, "credits", timed text and media hashes. Many of these feel like things that are more general than this use-case, anyway.
- AtomMedia reduces the media metadata considerably: it has only width/height for visual things and duration for time-based things. Some of the other attributes (fileSize, lang, type, ...) have equivalents in generic Atom and are thus omitted.
I would argue that there are two use-cases: One is basic aggregation, and the other is creating "far-side" portals, for instance in putting together http://podcast.steeple.org.uk . Perhaps for basic aggregation, the list of attributes could be reduced. However, certainly for "far-side" portals (and server-portal communication within institutions), a richer set of attributes is needed.
We suggest here Media rss media group element, that we might want to extend the media attributes of media rss, to make far-side portals easier. More details at http://www.steeple.org.uk/Portal
EXAMPLE MOVED HERE: Enclosures in yahoo media, rss, and atom