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1 LinkedMedia: An approach to online media re-use Lyndon Nixon MODUL University Vienna [email protected] RE-USING MEDIA ON THE (SEMANTIC) WEB ISWC2014 Tutorial, Riva de Garda, Italy, October 20 2014

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The second session looks at how using Linked Data principles for media fragment annotation publication and retrieval (Linked Media) can enable online media fragment re-use: Introducing the Linked Media principles Publishing Linked Media using dedicated multimedia RDF repositories Retrieval of media resources that illustrate linked data concepts Using the Linked Data graph to find relevant links between distinct media assets (examples with SPARQL) Retrieval of links between annotated media to enable topical browsing (using the TVEnricher service) Examples of Linked Media at scale: VideoLyzard and HyperTED

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Page 1: Remixing Media on the Semantic Web (ISWC2014 Tutorial) Pt 2  Linked Media: An approach to online media annotation and re-use

1

LinkedMedia:An approach to online media re-use

Lyndon NixonMODUL University [email protected]

RE-USING MEDIA ON THE (SEMANTIC) WEBISWC2014 Tutorial, Riva de Garda, Italy, October 20 2014

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Agenda

• Session 1: Media fragment specification and semantics• Summary: Introduce the W3C Media Fragment URI specification

and the Open Annotation model. Highlight how media fragments can be annotated using NER tools.

• Session 2: Linked Media principles• Summary: Introduce the Linked Media principles. How to

publish Linked Media in RDF and how to retrieve media enrichments. Illustration with Linked Media applications.

• Session 3: User experience driven design of Linked Media applications• Summary: Present the Web and TV convergence. Describe

LinkedTV experience via two innovative applications.

2

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2/3: LinkedMedia

• Introducing the Linked Media principles

• Publishing Linked Media• LinkedTV Platform (Virtuoso)

• Retrieval of Linked Media• Enrichment of media (LinkedTV)• Browsing and linking media

(VideoLyzard, HyperTED)

3

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Linked Media

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„It is growing at more than 20% per annum, fuelled by increased demands for new programming and the huge saving it represents compared with shooting new footage. Interactive technology and the Internet will further contribute to the growth of the market as it makes stock footage cheaper and easier to locate and license.“ - http://moneyam.uk-wire.com/cgi-bin/articles/200201020827103514P.html

Why is Online Media important?

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Why Semantic Media?

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Why Linked Media?

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Why Linked Media?

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Why Linked Media?

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Why Linked Media?

From Lyndon Nixon, „The importance of Linked Media to the Future Web“slideshare.net/linkedtv/www-linked-media-keynote

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Linked Media Principles

1. Web media descriptions need a common representation of media structure

2. 2. Web media descriptions Web media descriptions need a common need a common representation of media representation of media contentcontent

3. 3. Web media descriptions need to use a Web media descriptions need to use a media ontology which supports description media ontology which supports description of both the structure and content of mediaof both the structure and content of media

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Linked Media Principles

4. 4. The descriptions of The descriptions of media in terms of media in terms of common common representations of representations of structure and content structure and content are the basis for deriving are the basis for deriving links across media on links across media on the Web (Linked Media) the Web (Linked Media)

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Linking Media

Prime Minister

South Africa President

Mozambique

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PublishingLinked Media

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Linked Media is Linked Data

Good news: Linked Media can be published as Linked Data!

•The media resource has a globally (Web wide) unique identifier•Metadata about the media resource can be accessed via its identifier•Media identifier can‘t be = media locator!

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LinkedTV Platform

Web administration interface & REST API athttp://api.linkedtv.eu

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Media Resource view

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Media Metadata view

http://data.linkedtv.eu is the base of the RDF graph of LinkedTV content, and via Virtuoso, every LinkedTV instance URI can return HTML or RDF, e.g.http://data.linkedtv.eu/mediaresource/8a8187f2-3fc8-cb54-0140-7dccd76f0001

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Media Metadata view

Media fragments of a media resource:

http://data.linkedtv.eu/mediaresource/8a8187f2-3fc8-cb54-0140-7dccd76f0001/mediafragment

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Media Metadata view

Annotations of a media fragment:

http://data.linkedtv.eu/mediafragment/3d5b11e0-f6df-11e3-b0fe-005056a7235c%23t=1,299/annotation

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Linked Mediaretrieval

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SPARQL endpoint

SPARQL queries allow us to connect metadata across the Linked Media store AND to connect it to other metadata outside in the Linked Data cloud.

Linked Media queries courtesy LinkedTV deliverable 2.4 „Annotation and retrieval module of media fragments“ (Jose Luis Redondo Garcia & Raphael Troncy) available from:http://de.slideshare.net/linkedtv/annotation-and-retrieval-module-of-media-fragments

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SPARQL queries

Get all Shots or Chapters for a media resource.

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SPARQL queries

Return all entities of type nerd:Person in the annotation of a media resource.

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SPARQL queries

Return all entities occurring within a temporal boundary of a media resource.

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LinkedTV

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Why Linked Television?

40% of TV viewers are using a companion device alongside the TV program.*

* J. Abreu, P. Almeida, B. Teles, and M. Reis. Viewer behaviors and practices in the (new) television environment. In Proceedings of the 11th European Conference on Interactive TV and Video, EuroITV '13.

http://www.linkedtv.eu

Ever saw something on TV

and wanted to know more about it, but didn‘t even know how to search for

it?

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LinkedTV Technology

“...schilderij van Jan Sluijters....”

Video object and word detection

dbpedia.org/resource/Jan_Sluyters

Connection to concepts

Paintings by Jan Sluijters

Selection of related concepts

Selection of related content

Presentation engine

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Related concepts

Additional information, e.g. biography of artist style of painting

Related information, e.g. artists from same

period paintings in similar style related styles

Paintings by Jan Sluijters

Expansion of related concepts

Jan Sluijters

has art style

luminism

Leo Gestel

Piet Mondriaan

has art style

has art style

The use of Linked Data in the identification of concepts in LinkedTV means we can expand concepts along different facets, i.e. allow users to explore in terms of their different interests in a given concept.For example, for an artist like Jan Sluijters, LinkedTV can link into:

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Related content

LinkedTV provides enrichment services which provide recommendations for related online content (Web pages, images, audio, video) pertaining to the concepts in the TV program:– Fresh Social Web content coming

from e.g. Twitter and Facebook– User Generated content coming

from e.g. Flickr and YouTube– Whitelist content coming from

partner Websites like public broadcasters in Germany or cultural heritage archives in the Netherlands

– Extendable and configurable by source and media type

Linking to related content

… and their digital images

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LinkedTV „enrichment“

Base enrichments: title, thumbnail (poster), description (abstract)

Information cards: set of properties and values according to the entity type

Linksets: links to online content determined by queries over Web content sources using a group of entities as search term•Linksets can be split along enrichment dimensions•Dimensions are distinct aspects of interest to viewers•They map to different queries & services in LinkedTV

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LinkedCulture enrichment

TKK Video

Chapter segmentation + tagging as „Art Object“

TV2RDF incl. Art Object annotation

RelatedTKK chapters(Solr)

Relatedart objects (Europeana)

RelatedWhite List media(IRAPI)

TVEnricher (TKK configuration)

Editor Tool LinkedTV Player

Entity Proxy

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Art objects in TKK episodes

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Art object: semantic model

http://data.linkedtv.eu/object/avro/8a8187f2-3fc8-cb54-0140-7dccd76f0001/2138

A silver tea jar

RDF Is-a Container http://vocab.getty.edu/aat/300045611

CRM Consists-of Silver http://vocab.getty.edu/aat/300010975

VRA locationCreationSite

Friesland http://www.geonames.org/2755812

DCT temporal Start: 1690, End: 1742

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Mapping to Europeana API

http://data.linkedtv.eu/object/avro/8a8187f2-3fc8-cb54-0140-7dccd76f0001/2138

A silver tea jar

RDF Is-a Container

CRM Consists-of Silver

VRA locationCreationSite

Friesland

DCT temporal Start: 1690, End: 1742

what:(container+OR+houder+OR+bak+OR+tank+OR+blik) proxy_dc_format:zilver

where:Friesland 

YEAR:[1690+TO+1742]

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Enrichment results

Friesian silver from 1690 to 1742 to 1742

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LinkedNews enrichment

RBB Video

Chapter segmentation + tagging as „News Item“

Named Entity Expansion over news items

Relatednews items (Solr)

Relatednews articles (TVNews-Enricher)

RelatedWhite List media(IRAPI)

TVEnricher (RBB configuration)

Editor Tool LinkedTV Player

Entity Proxy

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Entity Proxy

Fill information cards for entities giving values for their most relevant properties.

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TVNewsEnricher

Returns news media sources related to given entity sets, powered by Google CSE

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IRAPI: Web media crawler

Extract descriptions of media on websites so that related media can be found

Video

TitleDescription

Entities, e.g. http://dbpedia.org/resource/Edward_

Snowden

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VideoLyzard

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Climate Change Portal

42

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VideoLyzard

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http://link.weblyzard.com/video-showcase

Videofragments in search results

Videofragment playback

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VideoLyzard

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VideoLyzardMore Negative More Positive

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HyperTED

Content courtesy EURECOM (José Luis Redondo García, Raphael Troncy, Mariella Sabatino & Pasquale Lisena)

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1984

.com

2006

CHAPTERS

2014

HOT SPOTS

ENTITIES

RELATED TED’S

CHAPTERS

THE MYSTERIOUS

FIELD OF ENGINEERING

SYSTEMS

UNDERSTANDING

ENVIRONMENT:

A SYSTEM APPROACH

SYSTEMS PRACTICE: MANAGING SUSTAINABI

LITY

COURSES

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HotspotsCluster video chapters which share similar topics

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Architecture

49

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Demo

http://linkedtv.eurecom.fr/HyperTED

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MediaMixer community portal

Introduction to all technologies at community.mediamixer.eu/technology

Updated with latest materials on all Media Mixer topics:

Technology use cases Demonstrators Tutorials Presentations Software Specifications

http://community.mediamixer.eu

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VideoLecturesMashup

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MediaMixer use case: VideoLecturesMashup

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Video fragment creation

Fragments were created based on the slide synchronisation timeline.

Transcripts (auto-generated by speech-to-text technology where necessary) were parsed and split across fragments.

… there are three Kingdoms of Life, Bacteria, Archaea and Eukaryota...

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Video fragment annotation

Fragments were then annotated by extracting topics from their textual metadata (slide OCR or speaker transcription).

Topics are connected to a global knowledge model (DBPedia).

Video Fragment (4:41-5:12)

Archaea

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Video fragment management

Annotations are managed in a separate metadata store.

The store provides a semantic query endpoint returning lists of video fragments matching a query topic (including semantically related topics)

Archaea

Acidiplasma „type“ relation

Video Fragment (4:41-5:12)

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Video fragment playback

The front end uses HTML5 or Flash. Both codebases are extended to support video fragment playout.

Individual playback can be modified to linear or non-linear channels (for e.g. a TV or mobile video experience)

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VideoLecturesMashup - demo

http://mediamixer.videolectures.net

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Reference

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SPARQL RDF query language

RDF data is a „labeled, directed graph“ without any fixed vocabulary (this is defined in RDF Schema). A query language for RDF needs to support this data model:•Tranversing paths in a RDF graph•Being independent of any defined vocabulary•Able to query over the data or the schema

SPARQL („sparkle“) is a W3C standard supported in most RDF tools•SELECT... WHERE.... constructions like in SQL•Path expressions•Additional keywords for more query expressiveness

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Examples: triple patterns

The basic idea in SPARQL is to match graph patterns against RDF graphs.To understand graph patterns we must first define triple patterns:• A triple pattern is similar to a triple (in RDF) but with one or more variables in the place of a RDF resource (URI or literal)

Triple: dbpedia:Lou_Reed foaf:givenName „Lewis Allen Reed“ .

Triple pattern: dbpedia:Lou_Reed foaf:givenName ?name .

?name is the variable. If a RDF graph with the above triple is queried with the below triple pattern, then in the SPARQL results the variable ?name would be ‚bound‘ to the value „Lewis Allen Reed“.

• A SPARQL query result is a set of bindings for the variables appearing in the SELECT clause, based on matching RDF resources to variables in triple patterns in the WHERE clause. .

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Examples: conjunctive and disjunctive query

In graph patterns, several triple patterns are listed within braces { ... } and these are interpreted conjunctively:

Ex: { ?what tech:noOfWheels „4“ . ?what tech:minSpeed „180“ . }

The variable ?what will only be bound to resources which BOTH have 4 wheels AND a minimum speed of 180.

You can also join results from distinct graph patterns using the UNION keyword. Note that result sets from graph patterns and from UNIONs are different, since UNION works disjunctively:

Ex: { ?what tech:noOfWheels „4“ . } UNION { ?what tech:minSpeed „180“ . }

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Examples: FILTER, ORDER BYSPARQL has many other keywords. FILTER restricts variable bindings returned in query results to those for which the filter expression evaluates to true. A filter applies to solutions over the entire graph pattern it is contained in.

Ex: { ?what tech:noOfWheels „4“ . ?what tech:minSpeed ?speed .

FILTER ( ?speed > 170 ) }

The ORDER BY keyword determines the sequence of query results returned according to a sort on the referenced variable‘s bindings, ascending by default:

Ex: { ?what tech:minSpeed ?speed . }ORDER BY ?speed

Or ORDER BY DESC(?speed)

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Query for media fragments: SPARQL-MMResearch work in progress: extending SPARQL to Media Fragments by adding spatio-temporal filter and aggregration functions.

Relation Function Aggregation Function

Spatial mm:rightBeside mm:spatialIntersection

mm:spatialOverlaps mm:spatialBoundingBox

… …

Temporal mm:after mm:temporalIntersection

mm:temoralOverlaps mm:temporalIntermediate

… …

Combined mm:overlaps mm:boundingBox

mm:contains mm:intersection

Courtesy Thomas Kurz (Salzburg Research) & MICO EU projecthttp://demos.mico-project.eu/sparql-mm/sparql-mm/demo/index.html