Refactored code for the Boobook owl

Issue #370

src/AnalysisConfigFiles/RecognizerConfigFiles/Towsey.NinoxBoobook.yml

@@ -26,17 +26,25 @@ Profiles:
 
 #################### POST-PROCESSING of EVENTS ###################
 
-# A: First post-processing steps are to combine overlapping/proximal/sequential events 
+# The first two post-processing steps are to combine overlapping/proximal/sequential events 
 #  1: Combine overlapping events
 CombineOverlappingEvents: true
 
-#  2: Combine each pair of Boobook syllables as one event
-#     Can also use this to "mop up" events in neighbourhood - these can be removed later. 
-CombinePossibleSyllableSequence: true
-SyllableStartDifference: 0.6
-SyllableHertzGap: 350
+# 2: Combine possible syllable sequences
+#    Can also use this to "mop up" events in neighbourhood - these can be removed later. 
+SyllableSequence:
+    CombinePossibleSyllableSequence: true
+    SyllableStartDifference: 0.6
+    SyllableHertzGap: 350
+    FilterSyllableSequence: true
+    SyllableMaxCount: 2
+    ExpectedPeriod: 0.4 
 
-#  B: Filter the events for excess activity in their upper and lower buffer zones
+# 3: Remove events whose bandwidth lies outside 3 SDs of an expected value.
+ExpectedBandwidth: 280
+BandwidthStandardDeviation: 40
+
+# 4: Filter the events for excess activity in their upper and lower buffer zones
 NeighbourhoodLowerHertzBuffer: 150
 NeighbourhoodUpperHertzBuffer: 400
 NeighbourhoodDbThreshold: 9.0

src/AnalysisPrograms/Recognizers/Birds/NinoxBoobook.cs

@@ -91,46 +91,30 @@ public override RecognizerResults Recognize(
                 outputDirectory,
                 imageWidth);
 
-            // ################### POST-PROCESSING of EVENTS ###################
-            // Following two commented lines are different ways of casting lists.
-            //var newEvents = spectralEvents.Cast<EventCommon>().ToList();
-            //var spectralEvents = events.Select(x => (SpectralEvent)x).ToList();
-
+            var count = combinedResults.NewEvents.Count;
+            BoobookLog.Debug($"Event count before post-processing = {count}.");
             if (combinedResults.NewEvents.Count == 0)
             {
-                BoobookLog.Debug($"Return zero events.");
                 return combinedResults;
             }
 
-            // 1: Filter the events for duration in seconds
-            // Get the BoobookSyllable config.
-            const string profileName = "BoobookSyllable";
-            var configuration = (NinoxBoobookConfig)genericConfig;
-            var chirpConfig = (ForwardTrackParameters)configuration.Profiles[profileName];
-            var minimumEventDuration = chirpConfig.MinDuration;
-            var maximumEventDuration = chirpConfig.MaxDuration;
-            if (genericConfig.CombinePossibleSyllableSequence)
-            {
-                minimumEventDuration *= 2.0;
-                maximumEventDuration *= 1.5;
-            }
-
-            combinedResults.NewEvents = EventExtentions.FilterOnDuration(combinedResults.NewEvents, minimumEventDuration.Value, maximumEventDuration.Value);
-            BoobookLog.Debug($"Event count after filtering on duration = {combinedResults.NewEvents.Count}");
+            // ################### POST-PROCESSING of EVENTS ###################
+            // Following two commented lines are different ways of casting lists.
+            //var newEvents = spectralEvents.Cast<EventCommon>().ToList();
+            //var spectralEvents = events.Select(x => (SpectralEvent)x).ToList();
 
-            // 2: Filter the events for bandwidth in Hertz
-            double average = 280;
-            double sd = 40;
-            double sigmaThreshold = 3.0;
-            combinedResults.NewEvents = EventExtentions.FilterOnBandwidth(combinedResults.NewEvents, average, sd, sigmaThreshold);
-            BoobookLog.Debug($"Event count after filtering on bandwidth = {combinedResults.NewEvents.Count}");
+            //NOTE:
+            // The generic recognizer does some post-processing of events prior to returning the list of combined events.
+            // Its post-processing steps are determined by config settings.
+            // Generic post processing step 1: Combine overlapping events.
+            // Generic post processing step 2: Combine possible syllable sequences and filter on excess syllable count.
+            // Generic post processing step 3: Remove events whose bandwidth is too small or large.
+            // Generic post processing step 4: Remove events that have excessive noise in their side-bands.
 
-            // 3: Filter on COMPONENT COUNT in Composite events.
-            int maxComponentCount = 2;
-            combinedResults.NewEvents = EventExtentions.FilterEventsOnCompositeContent(combinedResults.NewEvents, maxComponentCount);
-            BoobookLog.Debug($"Event count after filtering on component count = {combinedResults.NewEvents.Count}");
+            // The following post processing steps are specific for this species recognizer:
+            // 1: Pull out the chirp events and calculate their frequency profiles.
+            //    Filter chirp events based on their frequency profiles.
 
-            // 4: Pull out the chirp events and calculate their frequency profiles.
             var (chirpEvents, others) = combinedResults.NewEvents.FilterForEventType<ChirpEvent, EventCommon>();
 
             // Uncomment the next line when want to obtain the event frequency profiles.
@@ -143,8 +127,7 @@ public override RecognizerResults Recognize(
 
             if (combinedResults.NewEvents.Count == 0)
             {
-                BoobookLog.Debug($"Return zero events.");
-                return combinedResults;
+                BoobookLog.Debug($"Zero events after post-processing.");
             }
 
             //UNCOMMENT following line if you want special debug spectrogram, i.e. with special plots.