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Re: XMP [Re: RDF: XULing or Grueling]

From: Bruce D'Arcus <bdarcus@gmail.com>
Date: Sun, 07 Oct 2007 22:44:01 -0400
Message-ID: <47099971.70909@gmail.com>
To: Bijan Parsia <bparsia@cs.man.ac.uk>
CC: Tony Hammond <tony.hammond@gmail.com>, SW-forum Web <semantic-web@w3.org>

Bijan Parsia wrote:

> Thanks for the pointers. I don't have much to say that I've not already 
> said. The issues you discuss vis-a-vis XMP seem more political than 
> technical. Clearly, there is a requirement for extensibility. Beyond 
> that, it's a bit hard to determine what the actual technical 
> requirements are (no surprise, really). I wonder if aligning XMP with 
> some RDFa profile would make sense.

The political and the technical are hard to distinguish though.

 From what I know, somewhere around 2000, Adobe engineers were looking 
for an extensible metadata framework that could be mapped to a GUI 
reliably, without external configuration.

So they looked at RDF as it existed and said, "ah, RDF literals are kind 
of like a hash, rdf:Seq, rdf:Bag, and rdf:Alt can be mapped to familiar 
programming structures and UIs, let's just create a subset that only 
allows those."

So it's a bizarre sort of subset; not of the syntax, but of the model. 
It leans heavily on literals and blank nodes.

The spec is now effectively frozen by Adobe, which has a ton of legacy 
issues that explain why they have no interest in turning it over to a 
proper standards organization, or otherwise changing it.

Hence, the technical problems are closely connected to the political.

> Actually, I think there's a lot of milage to be gotten out of being less 
> free and easy. 

Which I guess aligns with periodic discussions of what has been called 
"RDF Lite."

> One problem we faced at UMD with some of our tools is 
> that they were *too* open and flexible. Photostuff, for example, would 
> build forms for "person" from all the ontologies you loaded. So you got 
> these HUGE forms with dozens of fields. And all you wanted to do was 
> mark up the photo with the fact that it was a photo of your niece.

Norm Walsh had started to work on a cool web app for photo metadata. In 
that case, the UI gets configured.

<http://norman.walsh.name/2006/09/13/photodata>

Bruce
Received on Monday, 8 October 2007 02:44:12 GMT

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