rdsf:seeAlso and owl:sameAs values in your example are literals, not resources.
On Sat, Jan 24, 2015 at 12:03 AM, Larry Masinter <[email protected]> wrote: > I wrote: >> > Image formats like JPEG and PNG (for which there >> > is support for XMP) don't have a standard, uniform >> > way of attaching other files, though, so allowing >> > data (or a pointer to external data) in the XMP >> > would broaden the applicability. > > And Michael Brunnbauer replied: > > I am right that such a pointer to external data would have to be a literal? >> The way I read the XMP standard is that only literals, blank nodes, >> rdf:Bag and rdf:Seq are allowed as object of a triple. > > No, URI is allowed as a simple type in XMP, so I think all you need is a > Linked Data schema. > But XMP uses rdf:Bag with named components to hold structures, and the > ResourceRef structure can be used to link documents by the InstanceID GUID as > well as file location (ManageFrom). > > > http://www.adobe.com/content/dam/Adobe/en/devnet/xmp/pdfs/DynamicMediaXMPPartnerGuide.pdf > has some examples. > >> This would rule out standard options like: >> >> <this_document> rdfs:seealso <rdf_document_about_pdf_document> >> <this_document> owl:sameAs <pdf_document_uri> >> >> Which would enable agents to find and regognize RDF data about the >> document. > > <rdf:Description rdf:about="" > xmlns:pdf="http://ns.adobe.com/pdf/1.3/"; > xmlns:xmp="http://ns.adobe.com/xap/1.0/"; > xmlns:xmpMM="http://ns.adobe.com/xap/1.0/mm/"; > xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#"; > xmlns:owl_1_="http://www.w3.org/2002/07/owl#"; > xmlns:dc="http://purl.org/dc/elements/1.1/";> > <pdf:Producer>Microsoft® Excel® 2013</pdf:Producer> > <xmp:CreatorTool>Microsoft® Excel® 2013</xmp:CreatorTool> > <xmp:CreateDate>2015-01-21T09:26:54-08:00</xmp:CreateDate> > <xmp:ModifyDate>2015-01-23T14:55:44-08:00</xmp:ModifyDate> > <xmp:MetadataDate>2015-01-23T14:55:44-08:00</xmp:MetadataDate> > > <xmpMM:DocumentID>uuid:895A48D2-1F07-442F-A374-FB045D560C9B</xmpMM:DocumentID> > > <xmpMM:InstanceID>uuid:a3962424-bf4c-4e33-8475-013b5ad35ace</xmpMM:InstanceID> > <rdfs:seealso>http://example.org/rdf-document</rdfs:seealso> > <owl_1_:sameAs>http://5stardata.info/gtd-5.html</owl_1_:sameAs> > <dc:format>application/pdf</dc:format> > <dc:title> > > >
