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Default branch is now named default on git as well as hg, in case we ever want to switch to mirroring in the other direction
author Chris Cannam
date Thu, 27 Aug 2020 15:57:37 +0100
parents 581b1b150a4d
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@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@prefix dc: <http://purl.org/dc/elements/1.1/> .
@prefix mo: <http://purl.org/ontology/mo/> .
@prefix af: <http://purl.org/ontology/af/> .
@prefix event: <http://purl.org/NET/c4dm/event.owl#> .
@prefix tl: <http://purl.org/NET/c4dm/timeline.owl#> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
@prefix : <#> .


# Describe the signal we're annotating, and associate it with a
# timeline (the timeline is named as :base_timeline but never given
# any attributes in this document).  Any feature that is associated
# with the same timeline will be taken as derived from this signal.

:audio_signal a mo:Signal ;
        mo:available_as <file:///path/to/myfile.wav> ;
        mo:time :signal_interval .

:signal_interval a tl:Interval ;
                 tl:onTimeLine :base_timeline ;
                 tl:beginsAt "PT0"^^xsd:duration .


# A sparse feature event.

:event0 a af:Onset ;
        event:time :time0 .

:time0 a tl:Instant ;
       tl:onTimeLine :base_timeline ;
       tl:at "PT0.185759637S"^^xsd:duration .

# Alternatively we could write that with a blank node.

:event1 a af:Onset ;
        event:time [
                   a tl:Instant ;
                   tl:onTimeLine :base_timeline ;
                   tl:at "PT0.510839002S"^^xsd:duration ;
                   ] .


# For a dense feature, we need an appropriately sampled, windowed timeline.

:feature_timeline a tl:DiscreteTimeLine .

:feature_timeline_map a tl:UniformSamplingWindowingMap ;
               tl:rangeTimeLine :feature_timeline ;
               tl:domainTimeLine :base_timeline ;
               tl:sampleRate "44100"^^xsd:int ;
               tl:windowLength "1024"^^xsd:int ;
               tl:hopSize "512"^^xsd:int .


# ... and an interval, defined in terms of hops (the discrete steps of
# the windowed timeline).

:feature_interval a tl:Interval ;
                  tl:onTimeLine :feature_timeline ;
                  tl:beginsAt "0"^^xsd:int ;
                  tl:duration "5634"^^xsd:int .


# Then our feature is a signal that is on the interval we just
# described.  We associate it explicitly with the original audio
# signal, although presumably we could leave the association implicit,
# to be derived from the relationships between timelines, just as it
# is for the sparse features above.

:audio_signal af:signal_feature :feature1 .

:feature_signal_type rdfs:subClassOf af:DetectionFunction ;
          dc:title "Detection Function from Simple Percussion Onset Detector" .

:feature1 a :feature_signal_type ;
          mo:time :feature_interval ;
          af:dimensions "12 12345" ;
          af:value "0 0 0 0 0 0 0 1 2 3 1 24 236 123213 (etc)" .