|
Chris@0
|
1 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
|
|
Chris@0
|
2
|
|
Chris@0
|
3 <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
|
|
Chris@0
|
4
|
|
Chris@0
|
5 <head>
|
|
Chris@0
|
6 <title>Henry - a DSP-driving SPARQL end-point</title>
|
|
Chris@0
|
7
|
|
Chris@0
|
8 <style type="text/css" media="all">
|
|
Chris@0
|
9 @import url(style.css);
|
|
Chris@0
|
10 </style>
|
|
Chris@0
|
11
|
|
Chris@0
|
12 </head>
|
|
Chris@0
|
13
|
|
Chris@0
|
14 <body>
|
|
Chris@0
|
15
|
|
Chris@0
|
16
|
|
Chris@0
|
17 <a href="http://dbtune.org/"><h1 style="font-size: 250%;">DBTune.org</h1></a>
|
|
Chris@0
|
18
|
|
Chris@0
|
19 <div id="tagline">Henry - a DSP-driving SPARQL end-point<!-- - yves _at_ dbtune _dot_ org--></div>
|
|
Chris@0
|
20
|
|
Chris@0
|
21 <h2><a name="intro" id="intro"></a>1. Introduction</h2>
|
|
Chris@0
|
22
|
|
Chris@11
|
23 <p><b>Note:</b> This service is not currently available. This page is
|
|
Chris@11
|
24 retained for historical interest.</p>
|
|
Chris@11
|
25
|
|
Chris@0
|
26 <p>
|
|
Chris@0
|
27 This server hosts a <a href="http://www.w3.org/TR/rdf-sparql-query/">SPARQL</a>
|
|
Chris@0
|
28 end-point able to perform audio processing tasks to answer a particular query.
|
|
Chris@0
|
29 It builds on top of <a href="http://www.w3.org/TeamSubmission/n3/">N3</a> and <a href="http://www.cs.sunysb.edu/~kifer/dood/tr-tutorial.html">
|
|
Chris@0
|
30 Transaction Logic</a>. More details to come.
|
|
Chris@0
|
31 </p>
|
|
Chris@0
|
32
|
|
Chris@0
|
33 <p>
|
|
Chris@0
|
34 Henry therefore implements a Music-related <a href="http://www-personal.si.umich.edu/~rfrost/courses/SI110/readings/In_Out_and_Beyond/Semantic_Web.pdf">Semantic Web agent</a>:
|
|
Chris@0
|
35 an agent processing machine-readable web content and audio content
|
|
Chris@0
|
36 to publish new data.
|
|
Chris@0
|
37 </p>
|
|
Chris@0
|
38
|
|
Chris@0
|
39 <h2><a name="details" id="details"></a>2. Details</h2>
|
|
Chris@0
|
40 <p>
|
|
Chris@0
|
41 <a href="http://blog.dbtune.org/post/2007/12/12/HENRY%3A-A-small-N3-parser/reasoner-for-SWI-Prolog">Henry</a> was initally intended to be a small application
|
|
Chris@0
|
42 on top of a <a href="http://www.swi-prolog.org/">SWI-Prolog</a> <a href="http://code.google.com/p/km-rdf/source/browse/trunk/n3/n3_dcg.pl">N3 parser</a>,
|
|
Chris@0
|
43 interpreting parsed N3 rules as entailment rules within the <a href="http://e-culture.multimedian.nl/software/ClioPatria.shtml">SWI-Prolog
|
|
Chris@0
|
44 Semantic Web server</a>.
|
|
Chris@0
|
45 </p>
|
|
Chris@0
|
46
|
|
Chris@0
|
47 <p>
|
|
Chris@0
|
48 Now, Henry provides the ability to easily register new audio processing builtin predicates (which may be discovered at querying time).
|
|
Chris@0
|
49 Henry works on top of a quad-store <i>m</i> and a binary store <i>b</i>.
|
|
Chris@0
|
50 </p>
|
|
Chris@0
|
51
|
|
Chris@0
|
52 <p>
|
|
Chris@0
|
53 A simplistic version of the
|
|
Chris@0
|
54 behavior of Henry is the following.
|
|
Chris@0
|
55 When processing a SPARQL query <i>q</i>, Henry gets through the following steps:
|
|
Chris@0
|
56 <ol>
|
|
Chris@0
|
57 <li> For every newly appearing web identifier <i>i</i> in <i>q</i>, dereference it, and then:</li>
|
|
Chris@0
|
58 <ul>
|
|
Chris@0
|
59 <li>If the representation is RDF, store it in <i>m</i>. If <i>i</i> is a property and its representation
|
|
Chris@0
|
60 links to a built-in implementation matching the current platform, get it ;</li>
|
|
Chris@0
|
61 <li>If the representation is N3, store it in <i>m</i> and register the corresponding rules ;</li>
|
|
Chris@0
|
62 <li>If the representation is of a known mime-type, cache it in <i>b</i> ;</li>
|
|
Chris@0
|
63 </ul>
|
|
Chris@0
|
64 <li> For every triple pattern <i>p</i> in <i>q</i>, the possible solutions are:</li>
|
|
Chris@0
|
65 <ul>
|
|
Chris@0
|
66 <li>Instantiations of <i>p</i> in <i>m</i> ;</li>
|
|
Chris@0
|
67 <li>If <i>p</i> is in the head of a rule, solutions of step <i>2</i> with the body of the rule as <i>q</i> (plus a few extra things to deal
|
|
Chris@0
|
68 with equivalency, lists, existentials in the head, etc.) ;</li>
|
|
Chris@0
|
69 <li>If <i>p=(s_p,p_p,o_p)</i> where <i>p_p</i> is a built-in predicate, solutions derived using this built-in (update the state of <i>b</i> accordingly)</li>
|
|
Chris@0
|
70 </ul>
|
|
Chris@0
|
71 </ol>
|
|
Chris@0
|
72 </p>
|
|
Chris@0
|
73
|
|
Chris@0
|
74 <p>
|
|
Chris@0
|
75 This implementation is still in the early stages, and still a bit experimental, it may perfectly die horribly :-) A look at
|
|
Chris@0
|
76 the <a href="http://code.google.com/p/km-rdf/issues/list">issue tracker</a> may give insights on what is still buggy.
|
|
Chris@0
|
77 Also, the server running this service is quite.... slow :)
|
|
Chris@0
|
78 </p>
|
|
Chris@0
|
79
|
|
Chris@0
|
80
|
|
Chris@0
|
81
|
|
Chris@0
|
82 <h2><a name="use" id="use"></a>3. Using this service</h2>
|
|
Chris@0
|
83 <p>
|
|
Chris@0
|
84 There is a raw SPARQL end point at <pre>http://dbtune.org/henry/sparql/</pre>.
|
|
Chris@0
|
85 </p>
|
|
Chris@0
|
86 <p>
|
|
Chris@0
|
87 A <a href="http://dbtune.org/henry/store/">web interface</a> is also available. Get in the <b>Query database</b> page, make sure you choose <b>SPARQL</b>
|
|
Chris@0
|
88 as your query language, and check that the entailment is set to <b>n3</b> (it should be the default, anyway).
|
|
Chris@0
|
89 </p>
|
|
Chris@0
|
90
|
|
Chris@0
|
91 <p>
|
|
Chris@0
|
92 A query involving only builtins (no N3 rules) is the following. It computes MFCC models for two tracks and compute
|
|
Chris@0
|
93 their Kullback-Leiber divergence:
|
|
Chris@0
|
94 </p>
|
|
Chris@0
|
95 <pre>
|
|
Chris@0
|
96 select ?d
|
|
Chris@0
|
97 where
|
|
Chris@0
|
98 {
|
|
Chris@0
|
99 <http://dbtune.org/audio/Den-Nostalia.ogg> <http://purl.org/ontology/dsp/cache> ?local.
|
|
Chris@0
|
100 ?local <http://purl.org/ontology/dsp/aspl_decode> ?sig.
|
|
Chris@0
|
101 ?sig <http://purl.org/ontology/vamp/qm-mfccparameters> (?means1 ?vars1).
|
|
Chris@0
|
102
|
|
Chris@0
|
103 <http://dbtune.org/audio/Both-Axel.ogg> <http://purl.org/ontology/dsp/cache> ?local2 .
|
|
Chris@0
|
104 ?local2 <http://purl.org/ontology/dsp/aspl_decode> ?sig2.
|
|
Chris@0
|
105 ?sig2 <http://purl.org/ontology/vamp/qm-mfccparameters> (?means2 ?vars2).
|
|
Chris@0
|
106
|
|
Chris@0
|
107 ((?means1 ?vars1) (?means2 ?vars2)) <http://purl.org/ontology/dsp/mfcc_kldiv> ?d
|
|
Chris@0
|
108 }
|
|
Chris@0
|
109 </pre>
|
|
Chris@0
|
110
|
|
Chris@0
|
111 <p>
|
|
Chris@0
|
112 This is a pretty huge query!
|
|
Chris@0
|
113 But, using a simple <a href="http://code.google.com/p/km-rdf/source/browse/trunk/henry/dsp-n3/similarity.n3">N3 rule</a>, we can reduce that to the following query:
|
|
Chris@0
|
114 </p>
|
|
Chris@0
|
115
|
|
Chris@0
|
116 <pre>
|
|
Chris@0
|
117 PREFIX sim: <http://purl.org/ontology/similarity/>
|
|
Chris@0
|
118 SELECT ?sim
|
|
Chris@0
|
119 WHERE
|
|
Chris@0
|
120 {
|
|
Chris@0
|
121 (<http://dbtune.org/audio/Den-Nostalia.ogg> <http://dbtune.org/audio/Both-Axel.ogg>) sim:div ?sim
|
|
Chris@0
|
122 }
|
|
Chris@0
|
123 </pre>
|
|
Chris@0
|
124
|
|
Chris@0
|
125 <p>
|
|
Chris@0
|
126 Another example is the following, computing key change events as specified by the <a href="http://purl.org/ontology/af/">Audio Features
|
|
Chris@0
|
127 ontology</a>.
|
|
Chris@0
|
128 using the <a href="http://www.elec.qmul.ac.uk/digitalmusic/downloads/index.html#qm-vamp-plugins">key
|
|
Chris@0
|
129 detection Vamp plugin in the Queen Mary plugin set</a> and <a href="http://code.google.com/p/km-rdf/source/browse/trunk/henry/dsp-n3/vamp.n3">this N3
|
|
Chris@0
|
130 rule</a>:
|
|
Chris@0
|
131 </p>
|
|
Chris@0
|
132 <pre>
|
|
Chris@0
|
133 select ?start ?key where {
|
|
Chris@0
|
134 <http://dbtune.org/audio/Both-Axel.ogg> mo:encodes ?sig.
|
|
Chris@0
|
135 ?sig mo:time ?time.
|
|
Chris@0
|
136 ?time tl:timeline ?tl.
|
|
Chris@0
|
137 _:evt a af:KeyChange;
|
|
Chris@0
|
138 event:time [tl:at ?start; tl:timeline ?tl] ;
|
|
Chris@0
|
139 af:new_key ?key }
|
|
Chris@0
|
140 </pre>
|
|
Chris@0
|
141
|
|
Chris@0
|
142
|
|
Chris@0
|
143
|
|
Chris@0
|
144 <h2><a name="code" id="code"></a>4. Code</h2>
|
|
Chris@0
|
145 <p>
|
|
Chris@0
|
146 All the code is open source and available in our <a href="http://code.google.com/p/km-rdf">Google code project</a>.
|
|
Chris@0
|
147 </p>
|
|
Chris@0
|
148
|
|
Chris@0
|
149 <!--<h2><a name="missing" id="missing"></a>5. Things missing</h2>
|
|
Chris@0
|
150 <p>Linked data access!! We are implementing the mechanism we use in <a href="http://sonictruths.net/dm.html#SBSimilarity">SBSimilarity</a>.</p>
|
|
Chris@0
|
151 -->
|
|
Chris@0
|
152 <!--<h2><a name="ack" id="ack"></a>5. Acknowledgements</h2>
|
|
Chris@0
|
153 <p>
|
|
Chris@0
|
154 Thanks to David Pastor who wrote the <a href="http://www.vamp-plugins.org/">Vamp</a> to <a href="http://www.swi-prolog.org/">SWI-Prolog</a>
|
|
Chris@0
|
155 interface!
|
|
Chris@0
|
156 </p>-->
|
|
Chris@0
|
157
|
|
Chris@0
|
158 <script type="text/javascript">
|
|
Chris@0
|
159 var gaJsHost = (("https:" == document.location.protocol) ? "https://ssl." : "http://www.");
|
|
Chris@0
|
160 document.write(unescape("%3Cscript src='" + gaJsHost + "google-analytics.com/ga.js' type='text/javascript'%3E%3C/script%3E"));
|
|
Chris@0
|
161 </script>
|
|
Chris@0
|
162 <script type="text/javascript">
|
|
Chris@0
|
163 var pageTracker = _gat._getTracker("UA-3327144-3");
|
|
Chris@0
|
164 pageTracker._initData();
|
|
Chris@0
|
165 pageTracker._trackPageview();
|
|
Chris@0
|
166 </script>
|
|
Chris@0
|
167
|
|
Chris@0
|
168
|
|
Chris@0
|
169 </body>
|
|
Chris@0
|
170
|
|
Chris@0
|
171 </html>
|
|
Chris@0
|
172
|
