- From: Larry Masinter <masinter@adobe.com>
- Date: Tue, 20 Jan 2015 17:28:38 +0000
- To: Michael Brunnbauer <brunni@netestate.de>, Martynas Jusevi??ius <martynas@graphity.org>
- CC: Alfredo Serafini <seralf@gmail.com>, Paul Houle <ontology2@gmail.com>, "public-lod@w3.org" <public-lod@w3.org>
There's some background that you might find helpful in the discussion. PDF is now defined by ISO 32000. PDF has profiles, including PDF/A-3 http://www.digitalpreservation.gov/formats/fdd/fdd000360.shtml ISO 19005-3. PDF/A-3 defines how to add arbitrary file attachments to PDF. XMP http://en.wikipedia.org/wiki/Extensible_Metadata_Platform is (as of 2012) also an ISO standard, ISO 16684-1, a format-independent metadata representation that uses a restricted RDF/XML framework, but not arbitrary RDF/XML. A design from scratch today might make different choices, of course. But for those whose goal is deployment and integration with existing workflows, then reuse of what is widely deployed seems like a path worth investigating. And XMP is widely implemented not just for PDF but also for images, as a way of extending metadata beyond EXIF or IPTC. Putting linked data in compact form (CSV, for example) might makes sense, perhaps as a PDF/A-3 file attachment, if a document is a carrier of tabular data. 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. In choosing how to make five star open data work for file formats other than HTML, what other choices are there? Sure, not all PDFs have good quality XMP metadata, but not all HTML has quality RDFa or metadata either. Larry -- http://larry.masinter.net
Received on Tuesday, 20 January 2015 17:29:13 UTC