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<h1>Guidelines for the revision of the MAWG ontology example files</h1>
The <a href="http://www.w3.org/TR/2011/CR-mediaont-10-20110707">Ontology for
Media Resources 1.0</a> is now a Candidate Rec. In order to exit this phase,
the MA WG must fulfill the <a
href="http://www.w3.org/TR/2011/CR-mediaont-10-20110707/Overview.html#status">CR
exit criteria</a><br>
To do so we must provide for each format listed in the testsuite an associated
RDF/OWL file for correspondence between the core properties and the RDF
vocabulary. <br>
Each format  has at least one example file covering a subset or all of the
properties of the core vocabulary of the Media Ontology available for each
format (e.g some formats may not have a mapping to all the properties core set;
for example the "MP4" format does not have a property mapping to the
"identifier" property of the core vocabulary of the Media Ontology). For
formats providing an exemple using only a subset of the properties of the core
vocabulary, the missing properties will be highlighted in the corresponding
mapping tables.<br>
<br>
To achieve this goal, and produce valid examples, please follow the 3
procedures:<br>

<ul>
  <li><a href="#L417">1- RDF Example editing and validation</a></li>
  <li><a href="#Examples">2- Examples  validation with the Media
  Ontology</a></li>
  <li><a href="#3-Mapping_table_update">3- Mapping table update</a></li>
</ul>

<h2><a name="1-_RDF_File_editing_and_validation"></a><a name="L417"
id="L417">1- RDF File editing and validation</a></h2>
<pre><span style="font-family: Arial,Helvetica,sans-serif">The editing of your example must be done as described in the following :</span><br></pre>
<ul>
  <li>make sure that original examples and RDF files are consistent wrt the
    properties included</li>
  <li>for binary source files, provide a XML/text file with the extracted
    metadata (cf. EXIF example)</li>
  <li>make sure that RDF syntax is valid</li>
  <li>ensure xml declaration <em>&lt;?xml version="1.0"
    encoding="UTF-8"?&gt;</em></li>
  <li>ensure complete namespace declarations and prefixes</li>
  <li>check correct use of rdf:datatype</li>
  <li>define a MediaResource and link the description with it <br>
    <span style="font-style: italic;">&lt;ma:MediaResource rdf:about="your
    media ressource here"&gt;</span><br>
    <em>rdf:about</em> should reference the MediaResource being described, and
    not the source metadata file.</li>
  <li>use <em>owl:imports</em> in order to import the definitions of the media
    ontology which are needed by reasoners and ontology editing tools <br>
    <em>&lt;owl:Ontology&gt;&lt;owl:imports
    rdf:resource="http://www.w3.org/ns/ma-ont"/&gt;&lt;/owl:Ontology&gt;</em></li>
  <li>try to achieve completeness wrt the properties in the mapping tables</li>
  <li>make sure that the vocabulary used in the RDF file matches the ontology
    for media resources</li>
  <li>avoid any non-MAWG properties in the examples</li>
  <li>it has been decided to drop <em>ma:identifier</em> in the RDF
    representation, but use <em>rdf:about</em> and/or <em>rdf:ID</em>
  instead</li>
  <li>make sure that the datatypes are up to date, eg for those that were
    changed from double to decimal in recent revisions</li>
  <li>avoid double quotes for values</li>
  <li>add a comment with your name and version number.<br>
    <em>&lt;!-- created by hand by Thierry MICHEL (W3C) for Dublin Core example
    file : version 4 --&gt;</em></li>
</ul>

<p>Your RDF file should start like this:</p>

<p>&lt;?xml version="1.0" encoding="UTF-8"?&gt;<em></em><em></em><br>
<em>&lt;!-- created by hand by Thierry MICHEL (W3C) for Dublin Core example
file : version 4 --&gt; </em><br>
<em>&lt;rdf:RDF xmlns="http://www.w3.org/ns/ma-ont#</em>"<br>
<em>xmlns:ma="http://www.w3.org/ns/ma-ont#"<br>
xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"<br>
xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#"<br>
xmlns:owl="http://www.w3.org/2002/07/owl#"<br>
xmlns:xsd="http://www.w3.org/2001/XMLSchema#"<br>
xmlns:more="........." &gt;</em><span style="font-style: italic;"><br>
&lt;owl:Ontology&gt;</span><br style="font-style: italic;">
<span style="font-style: italic;">    &lt;owl:imports
rdf:resource="http://www.w3.org/ns/ma-ont"/&gt;</span><br
style="font-style: italic;">
<span style="font-style: italic;">&lt;/owl:Ontology&gt;</span><br>
</p>

<p>For example of valid RDF files please refer to <a
href="http://www.w3.org/2008/WebVideo/Annotations/drafts/metadata_formats/mpeg7_example.owl">MPEG7</a>,
<a
href="http://www.w3.org/2008/WebVideo/Annotations/drafts/metadata_formats/DC_example1.rdf">DublinCore</a>
or <a
href="http://www.w3.org/2008/WebVideo/Annotations/drafts/metadata_formats/EBUCoreXML_2_MaOntRDF_ITM528229.owl">EBU</a>
RDF files<br>
</p>

<h2><a name="2-_Examples_validation_with_the_Media"></a>2- <a name="Examples"
id="Examples">Examples  validation with the Media Ontology</a></h2>
The validation of your example vs the MA Ontology is done using Protege as
described following:<br>


<h3>1: Installation of required tools:</h3>
The Protege OWL editor [<a href="http://protege.stanford.edu/">1</a>] in
combination with the reasoners Pellet [<a
href="http://clarkparsia.com/pellet/">2</a>] and Fact++ [<a
href="http://owl.man.ac.uk/factplusplus/">3</a>] are used for the validation
purpose. <br>
(Since Fact++ doesn't support datatype reasoning fully [<a
href="http://www.w3.org/2007/OWL/wiki/Implementations">4</a>], I recommend the
usage of Pellet in first place. I use Fact++ to doublecheck the results)<br>
<br>
1.1: Get Protege<br>
Download Protege 4.0.2 from here (platform independent installer program):[<a
href="http://protege.stanford.edu/download/protege/4.0/installanywhere/">5</a>]<br>
Remark: I recommend to use Protege 4.0.2 and not the latest availabe version
(Prot訩 4.1 Release Candidate 5) since I have experienced problems with the
representation of anonymous nodes as well as reasoning issues.

<p>1.2 Install Protege<br>
Shouldn't be a big deal - just follow the installation instructions.</p>

<p>1.3 Get Pellet reasoner plug-in for Protege<br>
Download the reasoner plug-in from here: [<a
href="http://clarkparsia.com/pellet/protege/plugin/com.clarkparsia.protege.plugin.pellet.jar">6</a>]
and put the file in the "plugin" directory of your Protege installation.<br>
Alternatively the auto-update feature of Protege can be used to obtain the
reasoner plugin - for a detailed description, I refer to: [<a
href="http://clarkparsia.com/pellet/protege/">7</a>] </p>

<p>1.4 Get Fact++ reasoner plug-in for Protege<br>
Since this plug-in is already included in the Protege distribution, no
additinal installation steps are required<br>
</p>

<h3>2. Load your Media Ontology example<br>
</h3>
2.1 Start Protege and load your Media Ontology example<br>
Select "File -&gt; Open"<br>
<br>
Don't forget to add the owl:imports statement in your example ontolgy in order
to link to the Media Ontology definitions which are needed for reasoning.<br>
Example code: <span style="font-style: italic;">&lt;owl:Ontology&gt;
</span><span style="font-style: italic;">&lt;owl:imports
rdf:resource="http://www.w3.org/ns/ma-ont"/&gt;</span><span
style="font-style: italic;">&lt;/owl:Ontology&gt;</span><br>
<br>
After the example ontolgy has been loaded correctly, you should be able to
browse through the availabe concepts, properties and individuals by selecting
the respective tabs. <br>
Try to browse through the class hierarchy including subclasses ("Classes" tab)
in order to verify if the Media Ontology definitions (owl:imports assertion)
are present.  <br>


<h3>3 Perform reasoning</h3>
3.1 Reasoner selection<br>
In order to choose either Pellet (preferred) or Fact++, select "Reasoner -&gt;
Pellet", respectively "Reasoner -&gt; Fact++"

<p>3.2 Start reasoning<br>
Click "Reasoner -&gt; Classify..." and new knowledge based on the given ontolgy
information will be inferred.<br>
In case of an invalid ontolgy, the concerning reasoner errors will be reported
(Pellet reasoner).</p>

<p>3.3 Discover new inferred knowledge<br>
By using a reasoner it is possible:</p>

<p>3.3.1 infer super class memberships <br>
e.g. all individuals of class ma:VideoTrack are displayed as inferred members
of class ma:MediaFragment<br>
-&gt; go to the "Class" tab and then select "Inferred class hierarchy"</p>

<p>3.3.2 infer inverse property relations<br>
e.g. ma:hasCreator statement infers ma:hasCreated statement<br>
-&gt; go to the "Individuals" tab and browse through the individuals. Newley
inferred knowledge about individuals is highlighted using yellow background
color.</p>

<p>3.3.3 infer super properties relations<br>
e.g. ma:features statement infers ma:hasContributer statement <br>
-&gt; go to the "Individuals" tab and browse through the individuals. Newley
inferred knowledge about individuals is highlighted using yellow background
color.  </p>

<h2><a name="3-Mapping_table_update" id="3-Mapping_table_update"></a>3- Mapping
table update</h2>

<p>When your RDF example is done according to [<a
href="#1-_RDF_File_editing_and_validation">section1</a>] and validated with
Protege.as described in [<a
href="#2-_Examples_validation_with_the_Media">section 2</a>]<br>
Please fill in the corresponding <a
href="http://www.w3.org/2008/WebVideo/Annotations/drafts/ontology10/CR/mappings_tested/">mapping
table format</a> for your file. <br>
For each mapping table, there is now an extra column called "Tested". <br>
<br>
This column enables to track the ma properties for which there is a mapping to
the format and if it is used  (implemented) or not used in your RDF file for
that format. <br>
Please indicate in your format for each property: <br>
- "Yes" if the ma property has a mapping to your format and it is used in your
RDF example. <br>
- "No" if the ma property has a mapping to your format but if it *not used* in
your RDF example. <br>
- "N/A" if the ma property does not have a mapping to your format <br>
<br>
Please fill the HTML mapping table for your format linked from <br>
<a class="moz-txt-link-freetext"
href="http://www.w3.org/2008/WebVideo/Annotations/drafts/ontology10/CR/mappings_tested/">http://www.w3.org/2008/WebVideo/Annotations/drafts/ontology10/CR/mappings_tested/</a>
<br>
<br>
This will enable to fulfill the <a
href="http://www.w3.org/TR/2011/CR-mediaont-10-20110707/Overview.html#status">CR
exit criteria</a> introduced by the Director <br>
<br>
Each format listed in the testsuite for Ontology for Media Resources 1.0 has at
least one example file covering a subset or all of the properties of the core
vocabulary of the Media Ontology available for each format (e.g some formats
may not have a mapping to all the properties core set; for example the "MP4"
format does not have a property mapping to the "identifier" property of the
core vocabulary of the Media Ontology). <span style="font-weight: bold;">For
formats providing an example using only a subset of the properties of the core
vocabulary, the missing properties will be highlighted in the corresponding
mapping tables</span>. </p>
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