Institute of Information Systems & Information Management

RDFa-deployed Multimedia Metadata

Werner Bailer & Michael HausenblasGraz, 2007-08-10

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How?

RDFa-deployed Multimedia Metadata (ramm.x)

…enables existing multimedia metadata formats to enter the Semantic Web

… targets at self-descriptive media asset descriptions allowing to apply the follow-your-nose principle

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How?

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How?The cornerstones of ramm.x are RDFa Formalisations of Multimedia Vocabularies ramm.x vocabulary

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How? – RDFa

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How? – RDFaRDFa (cf. http://www.w3.org/2006/07/SWD/RDFa/) is a concrete syntax (serialisation) for RDF using

(HTML) attributes interpreting @href, @resource, @instanceof,

@rel, @rev, @property, @about, @content (just as microformats do)

but based on and representing the RDF graph model, the Semantic Web core data model

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How? – RDFaRDFa example (from Michael’s homepage)

<div href="foaf:Person" rel="rdf:type" about="http://sw-app.org/mic.xhtml#i">

My name is <span property="foaf:name">Michael Hausenblas</span> (also known as <span property="foaf:nick">mic.</span>) and I work at <a href="http://www.joanneum.at/iis/" rel="foaf:workplaceHomepage">JOANNEUM RESEARCH</a> in the field of media semantics. <div> <img src="http://sw-app.org/img/mic_2007_01.jpg" rel="foaf:depiction" alt="Picture of Michael"/> </div>

</div>

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How? – RDFaRDFa example (from Michael’s homepage) –

HTML rendering:

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How? – RDFaRDFa example (from Michael’s homepage) – extracted RDF:

Graph visualisation

<http://sw-app.org/mic.xhtml#i> a foaf:Person;foaf:name "Michael Hausenblas";

foaf:nick "mic." ;foaf:workplaceHomepage http://www.joanneum.at/iis/ ; foaf:depiction http://sw-app.org/img/mic_2007_01.jpg .

N3 notation

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How? – Multimedia Vocabularies

Formalisations of Multimedia Vocabularies, a

Report of the W3C Multimedia Semantics XG contains:

Existing Multimedia Metadata Formats Still Images Audio Content Audio-Visual Content Multimedia Presentations Describing Specific Domains Or Workflows Other Multimedia Metadata Related Formats

Multimedia Ontologies

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ramm.x – Vocabulary

ContainerMediaAssetDescription

Formalisation

using

deployedIn

URI

URI

toRDF

fromRDF

URI

URI

MediaAsset

nativeDescription

hasDescription

schemaURI

URI

formalDescription

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ramm.x – Example

This still image contains embedded Exif metadata. Using the RDFizer service http://www.kanzaki.com/test/exif2rdf, an RDF/XML representation of the Exif metadata (exif_example.rdf) can be obtained.

Aim: Deploy the Exif metadata with ramm.x in an XHTML document

Result: exif_example.html

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ramm.x – Example

<div about="#exif_formal" href="ramm:Formalisation" rel="rdf:type"> <span rel="ramm:schemaURI" href="http://www.kanzaki.com/ns/exif" /> <span rel="ramm:toRDF" href="http://www.kanzaki.com/test/exif2rdf" /></div>

<div about="#sample_mad" href="ramm:MediaAssetDescription" rel="rdf:type"> <span about="http://sw.joanneum.at/rammx/spec/example/exif_example.jpg" href="ramm:MediaAsset" rel="rdf:type"> <img src="http://sw.joanneum.at/rammx/spec/example/exif_example.jpg“ alt="An example still image." style="border: solid black 1px;" /> <span rel="ramm:hasDescription" href="#sample_mad" /> <p property="dc:title" datatype="xsd:string">An example still image.</p> </span> <span property="dcterms:created" content="2007-07-22T22:23:00Z„ datatype="xsd:date" /> <span rel="ramm:nativeDescription“ href="http://sw.joanneum.at/rammx/spec/example/exif_example.jpg" /> <span rel="ramm:using" href="#exif_formal" /></div>

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What is ramm.x NOT? Another RDF-based multimedia description

vocabulary, as, e.g., hAudio RDFa; A declarative vocabulary – just as other

standards (SPARQL, GRDDL, etc.) standardise not only a vocabulary, but also behaviour, or put in other words: operational semantics. Hence, classes and properties are defined along with their procedural impact;

A replacement for other technologies, nor can it exist on its own; it always needs a host language, e.g., (X)HTML, SMILE, SVG, etc. due to its dependency on RDFa.

Institute of Information Systems & Information Management

RDFa-deployed Multimedia Metadata

Werner Bailer & Michael HausenblasGraz, 2007-08-10