Happened on April 10, 1964

@prefix mo: <http://purl.org/ontology/mo/> .
@prefix : <#> .
@prefix dc: <http://purl.org/dc/elements/1.1/> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .

:performance
  a mo:Performance ;
  mo:performer <http://dbpedia.org/resource/Glenn_Gould> ;
  dc:date "1964-04-10"^^xsd:date .

At the Wilshire Ebell Theater

@prefix mo: <http://purl.org/ontology/mo/> .
@prefix : <#> .
@prefix dc: <http://purl.org/dc/elements/1.1/> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
@prefix event: <http://purl.org/NET/c4dm/event.owl#> .

:performance
  a mo:Performance ;
  mo:performer <http://dbpedia.org/resource/Glenn_Gould> ;
  dc:date "1964-04-10"^^xsd:date ;
  event:place <http://dbpedia.org/resource/Ebell_of_Los_Angeles> .

Performed Beethoven's Piano Sonata No. 30

@prefix mo: <http://purl.org/ontology/mo/> .
@prefix : <#> .
@prefix dc: <http://purl.org/dc/elements/1.1/> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
@prefix event: <http://purl.org/NET/c4dm/event.owl#> .

:performance
  a mo:Performance ;
  mo:performer <http://dbpedia.org/resource/Glenn_Gould> ;
  dc:date "1964-04-10"^^xsd:date ;
  event:place <http://dbpedia.org/resource/Ebell_of_Los_Angeles> ;
  mo:performance_of <http://dbpedia.org/resource/
                            Piano_Sonata_No._30_(Beethoven)> .

Save as glenn_gould_performance.n3

Checking that it parses...

Go to http://www.rdfabout.com/demo/validator/ and check your RDF (make sure to select "Turtle" in the input format drop-down list)

Or, if you have raptor-utils installed, just run the following from the command-line:

	$ rapper -i turtle glenn_gould_performance.n3
	

It should give 5 RDF triples

Querying from the command-line (1)

Give me places in which Glenn Gould played

Querying from the command-line (2)

PREFIX mo: <http://purl.org/ontology/mo/>
PREFIX event: <http://purl.org/NET/c4dm/event.owl#>
SELECT ?place
FROM <glenn_gould_performance.n3>
WHERE {
?performance
  mo:performer <http://dbpedia.org/resource/Glenn_Gould> ;
  event:place ?place
}

Save as places_in_which_glenn_gould_played.rq

Querying from the command-line (3)

Use roqet from the rasqal-utils package:

$ roqet places_in_which_glenn_gould_played.rq 

roqet: Querying from file places_in_which_glenn_gould_played.rq
roqet: Query has a variable bindings result
result: [place=uri<http://dbpedia.org/resource/Ebell_of_Los_Angeles>]
roqet: Query returned 1 results

Or use sparql.org (the file is at http://moustaki.org/resources/glenn_gould_performance.n3) - results

And now, for more Music Ontology

In the same way, we can describe more complex things:

• Annotations of an audio signal
• Events happening during a performance or a recording
• Symbolic information
• More examples

Structural annotations (1)

Can't buy me love

:signal owl:sameAs <http://dbtune.org/musicbrainz/resource/
                        signal/eb20ee61-414f-4eee-8dce-190db516a466>.
:signal mo:time [
     tl:duration "PT2M14S"^^xsd:duration;
     tl:timeline :tl;
  ].

Structural annotations (2)

:chorus1 a ps:Chorus;
     rdfs:label "First chorus";
     event:time [
        tl:timeline :tl;
        tl:start "PT0S"^^xsd:duration;
        tl:duration "PT9S"^^xsd:duration;
     ].

:verse1 a ps:Verse;
     rdfs:label "First verse";
     event:time [
        tl:timeline :tl;
        tl:start "PT9S"^^xsd:duration;
        tl:duration "PT33S"^^xsd:duration;
     ].

Decomposing a recording session

:rec a mo:Recording;
  rdfs:label "live recording of my band in studio";
  event:sub_event :guitar1, :guitar2, :drums1, :kick1, :sing.

:sing a mo:Recording;
  rdfs:label "Voice recorded with a SM58";
  event:factor rd:sm57;
  event:place [rdfs:label "Middle of the room"].

:kick1 a mo:Recording;
  rdfs:label "Kick drum using a Shure PG52";
  event:factor rd:pg52;
  event:place [rdfs:label "Kick drum microphone location"].

Symbolic information (1)

:compo
    a mo:Composition;
    event:product :syrinx_w ;
    event:product :syrinx_s .
:syrinx 
    a mo:MusicalWork;
    owl:sameAs <http://dbpedia.org/resource/Syrinx_%28Debussy%29> .
:syrinx_s 
    a mo:Score ;
    so:score_time :tl .

:tl a so:ScoreTimeLine.

Symbolic information (2)

:e000
    a so:DottedEighthNote ;
    so:pitch :b_flat ;
    event:time [
        tl:onTimeLine :tl ;
        tl:meets :e001 ;
    ] .
:e001
    a so:ThirtysecondNote ;
    so:pitch :a ;
    event:time [
        tl:onTimeLine :tl ;
        tl:meets :e002 ;
    ] .

Full example

Music Ontology extensions

Multiple extensions, to deal with:

• Music similarity
• Chords and keys
• Audio features
• Instrument taxonomy
• Symbolic information

Available Music Ontology data

Multiple sources of Music Ontology data, including:

• BBC Music, hosting around 15 million statements
• BBC Programmes, offering temporal segmentation of programmes
• DBtune, hosting 10 datasets and over 14 billion statements
• Discogs, hosting information about artists, labels and releases

MusicBrainz

A special mention for MusicBrainz, a community music database holding:

• around 500 000 artists
• around 700 000 releases
• and around 8.5 million tracks

Linked Data version and SPARQL end-point at dbtune.org/musicbrainz

The MusicBrainz schema

The MusicBrainz NGS

The MusicBrainz's Next Generation Schema adds:

• Musical works and performances (the thingy table)
• Release groups
• Recording (signals)...

Now really close to MO!

Breaking artificial domain boundaries

Extensibility

• URIs from different ontologies can be mixed and mashed
• There are ontologies for almost everything...
• ...and if a domain is missing, create your own

Artists and geolocation

<http://dbtune.org/jamendo/artist/5>
     a
      <http://purl.org/ontology/mo/MusicArtist> .


<http://dbtune.org/jamendo/artist/5> 
    <http://xmlns.com/foaf/0.1/based_near> 
       <http://sws.geonames.org/2991627/> .


<http://sws.geonames.org/2991627/> 
    a
      <http://www.geonames.org/ontology#Feature>

Why does it matter?

Compare that to other metadata formats...

Most of them are geared towards a specific application, preventing extensibility

The metadata format limits the context in which it can be used

• XSPF: playlisting
• MPEG-7: temporal annotations
• AceXML: machine learning
• WGS-84: geolocation

Using RDF, you can pick concepts from different places and adapt to any context

A sneak peek at the wider Linked Data world

The Linking Open Data (LOD) project

• Started in late 2006
• Following a design note from Tim Berners-Lee
• More and more sources of open data everywhere... but existing in isolation from one another
• A domain-independent effort to publish these as Linked Data and join them up
• One of the most successful project ran by the Semantic Web community...
• Now involves the US and the UK governments!

October 2007...

September 2008...

And July 2009

How are they related?

Gabriel Fauré

is the same as

was born in

is the same as

is located within

is located within

is the birth place of

is part of

has member

is spouse of

Getting back to our RDF example...

:performance
  a mo:Performance ;
  mo:performer <http://dbpedia.org/resource/Glenn_Gould> ;
  dc:date "1964-04-10"^^xsd:date ;
  event:place <http://dbpedia.org/resource/Ebell_of_Los_Angeles> ;
  mo:performance_of <http://dbpedia.org/resource/
                            Piano_Sonata_No._30_(Beethoven)> .

Three links to URIs within the Linked Data cloud

We can enrich that RDF by following links...

:performance
  event:place <http://dbpedia.org/resource/Ebell_of_Los_Angeles> .

Load the place in which Glenn Gould has played

Query for more information about that place...

Let's do it in python

We can use rdflib to parse local and remote RDF - get this data linked

install rdflib using Python EZ setuptools http://pypi.python.org/pypi/setuptools

	$ sudo easy_install rdflib -U "rdflib>=2.4"
	

Get the code in examples/scripts/glenn_gould_performance

Python code

$ python load_n_query.py 

Importing local RDF file: glenn_gould_performance.n3
Loading:
	http://dbpedia.org/resource/Ebell_of_Los_Angeles
Glenn Gould has played in:
	http://dbpedia.org/resource/Ebell_of_Los_Angeles
The Ebell of Los Angeles is a women's club housed in a complex in the 
Mid-City section of Los Angeles that includes a clubhouse building and 
the renowned 1,270-seat Wilshire Ebell Theatre. The complex has been 
owned and operated since 1927 by the Ebell of Los Angeles women's 
club, which was formed in Los Angeles in 1894.
It is at latitude 34.06166839599609 and longitude -118.3241653442383

Image credits

Selva

Nachomerlo

ZoomZoom

Richard Cyganiak and Anja Jentzsch

Wikipedia