Simon Dixon, Cedric Mesnage and Barry Norton (Centre for Digital Music, Queen Mary University of London). Music Linked Data Workshop, 12 May 2011, JISC, London.

1. LinkedBrainz Live!
Live
Simon Dixon, Cedric Mesnage, Barry Norton
Centre for Digital Music, Queen Mary
SPARQL
+ =
RDF
RDFa
HTTP
URIs

2. MusicBrainz
• MusicBrainz is “an open music encyclopedia ...
collects & makes available... music metadata”
• It aims to be:
– The ultimate source of music information
by allowing anyone to contribute and releasing
the data under open licenses.
– The universal lingua franca for music
by providing a reliable and unambiguous form of music
identification, enabling both people & machines to have
meaningful conversations about music.
• It currently describes >9M tracks, soon to be >30M
LinkedBrainz Live, Dixon, Mesnage and Norton
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Music Linked Data Workshop, 12th May 2011

3. Linked Data
• Defined in a W3C Technical Note including
these core principles:
1. Use URIs as names for things
2. Use HTTP URIs so that people can look up those
names.
3. When someone looks up a URI, provide useful
information, using the standards (RDF*, SPARQL)
4. Include links to other URIs. so that they can
discover more things.
LinkedBrainz Live, Dixon, Mesnage and Norton
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Music Linked Data Workshop, 12th May 2011

4. Linked Open Data
• The Linking Open Data (LOD) project of the
W3C Semantic Web Outreach and Education
Task Force has
developed a
good deal of
best practice
and exposed
a large number
of interlinked datasets
LinkedBrainz Live, Dixon, Mesnage and Norton
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Music Linked Data Workshop, 12th May 2011

5. Comparison of MusicBrainz & LOD 1
• MusicBrainz is a relational schema where
(internal) primary keys are externalised as
UUIDs, “Universally Unique” Identifiers
• Disambiguation easier if entity type included:
• artist/
1. Use URIs as names for things b10bbbfc-cf9e-42e0-be17-e2c3e1d2600d
2. Use HTTP URIs so that people can look up (The Beatles)
those names.
3. When someone looks up a URI, provide useful • recording/
information, using the standards (RDF*, SPARQL) efe365d3-a1d8-42dc-a63d-0b4cc6ecfaed
4. Include links to other URIs. so that they can (‘With a Little Help from my Friends’)
discover more things.
LinkedBrainz Live, Dixon, Mesnage and Norton
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Music Linked Data Workshop, 12th May 2011

6. Comparison of MusicBrainz & LOD 2
http://musicbrainz.org/artist/b10bbbfc-cf9e-42e0-be17-e2c3e1d2600d
1. Use URIs as names for things
2. Use HTTP URIs so that people can look up
those names.
3. When someone looks up a URI, provide useful
information, using the standards (RDF*, SPARQL)
4. Include links to other URIs. so that they can
discover more things.
LinkedBrainz Live, Dixon, Mesnage and Norton
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Music Linked Data Workshop, 12th May 2011

7. Comparison of MusicBrainz & LOD 3
<?xml version="1.0" encoding="UTF-8"?>
<metadata xmlns="http://musicbrainz.org/ns
/mmd-1.0#">
<artist id="b10bbbfc-cf9e-42e0-be17-e2c3e1d2600d" type="Group">
<name>The Beatles</name>
<sort-name>Beatles, The</sort-name>
<life-span begin="1957" end="1970-04-10"/>
</artist>
</metadata>
http://musicbrainz.org/ws/1/artist/b10bbbfc-cf9e-42e0-be17-e2c3e1d2600d?type=xml
http://musicbrainz.org/artist/b10bbbfc-cf9e-42e0-be17-e2c3e1d2600d
1. Use URIs as names for things
2. Use HTTP URIs so that people can look up
those names.
3. When someone looks up a URI, provide useful
information, using the standards (RDF*, SPARQL)
4. Include links to other URIs. so that they can
discover more things.
LinkedBrainz Live, Dixon, Mesnage and Norton
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Music Linked Data Workshop, 12th May 2011

8. Comparison of MusicBrainz & LOD 2’
• Non-informational resource:
http://musicbrainz.org/artist/b10bbbfc-cf9e-42e0-be17-e2c3e1d2600d#_
• Informational resources:
http://musicbrainz.org/ws/1/artist/b10bbbfc-cf9e-42e0-be17-e2c3e1d2600d?type=rdf
http://musicbrainz.org/ws/1/artist/b10bbbfc-cf9e-42e0-be17-e2c3e1d2600d?type=xml
http://musicbrainz.org/artist/b10bbbfc-cf9e-42e0-be17-e2c3e1d2600d
1. Use URIs as names for things
2. Use HTTP URIs so that people can look up
those names.
3. When someone looks up a URI, provide useful
information, using the standards (RDF*, SPARQL)
4. Include links to other URIs. so that they can
discover more things.
LinkedBrainz Live, Dixon, Mesnage and Norton
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Music Linked Data Workshop, 12th May 2011

9. Comparison of MusicBrainz & LOD 4
1. Use URIs as names for things
2. Use HTTP URIs so that people can look up
those names.
3. When someone looks up a URI, provide useful
information, using the standards (RDF*, SPARQL)
4. Include links to other URIs. so that they can
discover more things.
LinkedBrainz Live, Dixon, Mesnage and Norton
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Music Linked Data Workshop, 12th May 2011

10. MB Next Generation Schema
• Artist
As before, but further
attributes
• Artist Credit
Allows joint credit
• Release Group
Generalises
‘release type’ (cf. album) entity, cf.
• Release • Track • Work
• Medium • Track List • Recording
LinkedBrainz Live, Dixon, Mesnage and Norton
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Music Linked Data Workshop, 12th May 2011

11. Music Ontology
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Music Linked Data Workshop, 12th May 2011

12. Music Ontology
d2rq:ClassMap
d2rq:ClassMap
map:Recording a d2rq:ClassMap;
d2rq:dataStorage map:database;
map:recording_name a d2rq:PropertyBridge;
d2rq:class mo:Signal;
d2rq:belongsToClassMap map:Recording;
d2rq:classDefinitionLabela"Signal"@en;
map:recording_credit d2rq:PropertyBridge;
d2rq:property dct:title, rdfs:label;
... map:DBpediaTrans a d2rq:TranslationTable;
d2rq:uriPattern "recording/@@musicbrainz.recording.gid@@#_".
d2rq:join "musicbrainz.recording.name =>
d2rq:join "musicbrainz.recording.artist_credit =>
d2rq:javaClass "translators.WikipediaTranslator".
musicbrainz.track_name.id";
musicbrainz.artist_credit.id";
d2rq:column "musicbrainz.track_name.name".
d2rq:join "musicbrainz.artist_credit_name.artist_credit =>
map:artist_dbpedia a d2rq:PropertyBridge;
musicbrainz.artist_credit.id";
... d2rq:property owl:sameAs;
d2rq:join "musicbrainz.artist_credit_name.artist =>
... d2rq:condition "musicbrainz.link_type.id=213";
musicbrainz.artist.id". map:DBpediaTrans.
LinkedBrainz Live, Dixon, Mesnage and Norton
... d2rq:translateWith 12
Music Linked Data Workshop, 12th May 2011

13. RDFa Roll-out
<div class="recordingheader"
about="http://ngs.musicbrainz.org/recording/efe365d3-a1d8-42dc-a63d-0b4cc6ecfaed#_"
typeof="mo:Signal">
<h1>“<a rel="foaf:isPrimaryTopicOf"
href="http://ngs.musicbrainz.org/recording/efe365d3-a1d8-42dc-a63d-0b4cc6ecfaed"
property="dct:title rdfs:label" xml:lang="" datatype="">
With a Little Help From My Friends</a>” </h1>
<p class="subheader"> <span class="prefix">~</span>
Recording by
<a title="Beatles, The" rel="foaf:maker“
resource="[mbz:artist/b10bbbfc-cf9e-42e0-be17-e2c3e1d2600d#_]“
LinkedBrainz Live, Dixon, Mesange and Norton
href="http://ngs.musicbrainz.org/artist/b10bbbfc-cf9e-42e0-be17-e2c3e1d2600d"> 13
Music Linked Data Workshop, 12th May 2011
The Beatles</a></p></div>

14. Future Work
• Complete D2R mappings
– Regular dumps to be made available
– Deferencing to RDF from (NI) MB URIs
– SPARQL endpoint
– Completion of mappings (advanced relationships,
interlinkage to further datasets), consistency testing
• Tutorials on using LinkedBrainz
Summer School (23rd May)
Linked Services Tutorial (30th May)
LinkedBrainz Live, Dixon, Mesnage and Norton
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Music Linked Data Workshop, 12th May 2011