[whatwg] metadata attribute for media

[Ralph Giles]

On 12-12-11 4:58 PM, Ian Hickson wrote:

> This seems reasonable.

Thanks for the feedback. Anyone else? :-)

> I don't want to be the one to maintain the mapping from media formats to 
> metadata schema, because this isn't my area of expertise, and it isn't 
> trivial work.

Good point. This would need to be standardized for the fixed-schema
proposal, at least for the formats commonly supported by the HTML media
element. The Web Ontology working group has done some work here, as
Silvia mentioned.

> I don't think we should have an open-ended API without fixed names, 
> because that is a recipe for an interoperability disaster.

I agree it would have interoperability issues. My own implementation
experience is that the easy thing to do is to mirror whatever
representation your playback framework offers, which can result in
per-platform differences as well as per-media-format (and per tagging
application, etc.).

That said, I'm not convinced this is an issue given the primary
use-case, which is pretty much that web content wants to do more
sophisticated things with the metadata than the user-agent's
standardized parsing allows. If one cares to that extent, and is already
handling format differences, dealing with vendor variation on top isn't
that much more effort.

We could say that user-agents should represent the metadata dictionaries
as directly as possible, and to match the tag names from the schema spec
when that's not possible.

 -r