Now, assuming XMP is a good idea - and I think on balance it is (as blogged earlier), why are we not seeing any metadata published in scholarly media files? The only drawbacks that occur to me are:
Hard to write - it’s too damn difficult, no tools support, etc.
Hard to model - rigid, “simple” XMP data model, both complicates and constrains the RDF data model
thammond – 2007 October 12
thammond – 2007 October 09
thammond – 2007 October 08
Oh dear. Yesterday’s post “Using ISO URNs” was way off the mark. I don’t know. I thought that walk after lunch had cleared my mind. But apparently not. I guess I was fixing on eyeballing the result in RDF/N3 rather than the logic to arrive at that result.
thammond – 2007 October 01
(Update - 2007.10.02: Just realized that there were some serious flaws in the post below regarding publication and form of namespace URIs which I’ve now addressed in a subsequent post here.)
By way of experimenting with a use case for ISO URNs, below is a listing of the document metadata for an arbitrary PDF. (You can judge for yourselves whether the metadata disclosed here is sufficient to describe the document.) Here, the metadata is taken from the information dictionary and from the document metadata stream (XMP packet).
The metadata is expressed in RDF/N3. That may not be a surprise for the XMP packet which is serialized in RDF/XML, as it’s just a hop, skip and a jump to render it as RDF/N3 with properties taken from schema whose namespaces are identified by URI. What may be more unusual is to see the document information dictionary metadata (the “normal” metadata in a PDF) rendered as RDF/N3 since the information dictionary is not nodelled on RDF, not expressed in XML, and not namespaced. Here, in addition to the trusty HTTP URI scheme, I’ve made use of two particular URI schemes: “iso:” URN namespaces, and “data:” URIs.
2019 February 10
2019 February 07
2019 February 05