New method to find events

Issue-#238 Main work was to add a new method to AcousticEvents.cs in order to find events located at a score maximum. All such events have the same (user defined) time duration centred on the maximum.

src/AnalysisPrograms/Recognizers/PteropusSpecies.cs

@@ -102,8 +102,15 @@ internal static RecognizerResults Gruntwork(AudioRecording audioRecording, Confi
             string abbreviatedSpeciesName = configuration[AnalysisKeys.AbbreviatedSpeciesName] ?? "<no.sp>";
             int minHz = configuration.GetIntOrNull(AnalysisKeys.MinHz) ?? 500;
             int maxHz = configuration.GetIntOrNull(AnalysisKeys.MaxHz) ?? 8000;
-            double minDuration = configuration.GetIntOrNull(AnalysisKeys.MinDuration) ?? 0.1;
-            double maxDuration = configuration.GetIntOrNull(AnalysisKeys.MaxDuration) ?? 0.5;
+
+            //double minDuration = configuration.GetIntOrNull(AnalysisKeys.MinDuration) ?? 0.1;
+            //double maxDuration = configuration.GetIntOrNull(AnalysisKeys.MaxDuration) ?? 0.5;
+            var neighbourhoodDuration = TimeSpan.FromSeconds(0.05);
+
+            double intensityNormalisationMax = 12.0; // decibels
+            double intensityThreshold = 9.0; // decibels
+            var eventThreshold = intensityThreshold / intensityNormalisationMax;
+
 
             // Get a value from the config file - without a string accessor, as a double
             //double someExampleSettingA = configuration.GetDoubleOrNull("SomeExampleSettingA") ?? 0.0;
@@ -129,7 +136,7 @@ internal static RecognizerResults Gruntwork(AudioRecording audioRecording, Confi
 
             //######################
             //2.Convert each segment to a spectrogram.
-            double noiseReductionParameter = configuration.GetDoubleOrNull(AnalysisKeys.NoiseBgThreshold) ?? 0.1;
+            //double noiseReductionParameter = configuration.GetDoubleOrNull(AnalysisKeys.NoiseBgThreshold) ?? 0.1;
 
             // make a spectrogram
             var sonoConfig = new SonogramConfig
@@ -143,26 +150,24 @@ internal static RecognizerResults Gruntwork(AudioRecording audioRecording, Confi
             // now construct the standard decibel spectrogram WITH noise removal, and look for LimConvex
             // get frame parameters for the analysis
             var sonogram = (BaseSonogram)new SpectrogramStandard(sonoConfig, audioRecording.WavReader);
+            var intensityArray = SNR.CalculateFreqBandAvIntensity(sonogram.Data, minHz, maxHz, sonogram.NyquistFrequency);
 
-            var data = sonogram.Data;
-            var score = MatrixTools.GetRowAverages(data);
-            score = DataTools.NormaliseInZeroOne(score, 0, 12);
-            //var eventThreshold = 0.25; // equivalent to 3dB
-            var eventThreshold = 0.5; // equivalent to 6dB
-            var plot = new Plot(speciesName, score, eventThreshold);
+            //var data = sonogram.Data;
+            //var intensityArray = MatrixTools.GetRowAverages(data);
+            intensityArray = DataTools.NormaliseInZeroOne(intensityArray, 0, 12);
+            var plot = new Plot(speciesName, intensityArray, eventThreshold);
             var plots = new List<Plot> { plot };
 
             //iii: CONVERT decibel SCORES TO ACOUSTIC EVENTS
-            var acousticEvents = AcousticEvent.ConvertScoreArray2Events(
-                score,
+            var acousticEvents = AcousticEvent.GetEventsAroundMaxima(
+                intensityArray,
+                segmentStartOffset,
                 minHz,
                 maxHz,
                 sonogram.FramesPerSecond,
                 sonogram.FBinWidth,
                 eventThreshold,
-                minDuration,
-                maxDuration,
-                segmentStartOffset);
+                neighbourhoodDuration);
 
             // ######################################################################
             acousticEvents.ForEach(ae =>
@@ -182,11 +187,11 @@ internal static RecognizerResults Gruntwork(AudioRecording audioRecording, Confi
             //            Path.GetFileNameWithoutExtension(recording.BaseName), speciesName, "png", "DebugSpectrogram"));
             //sonoImage.Save(opPath.FullName);
 
-            string imageFilename = "Test.png";
+            string imageFilename = audioRecording.BaseName + ".png";
             sonoImage.Save(Path.Combine(outputDirectory.FullName, imageFilename));
 
             // get samples
-            var samples = audioRecording.WavReader.Samples;
+            //var samples = audioRecording.WavReader.Samples;
 
             // Profile example: running the same algorithm on every profile with different settings (regional variation)
             /*
@@ -262,7 +267,7 @@ private static List<AcousticEvent> RunFemaleProfile(configuration, rest of argum
 
 
             // get high resolution indices
-
+/*
 
             var foundEvents = new List<AcousticEvent>();
 
@@ -282,10 +287,10 @@ private static List<AcousticEvent> RunFemaleProfile(configuration, rest of argum
             };
 
             foundEvents.Add(anEvent);
-
+*/
             return new RecognizerResults()
             {
-                Events = foundEvents,
+                Events = acousticEvents,
                 Hits = null,
                 ScoreTrack = null,
 

src/AnalysisPrograms/Sandpit.cs

@@ -277,7 +277,8 @@ public static void Audio2CsvOverOneFile()
             //audio2csv  "C:\SensorNetworks\WavFiles\KoalaMale\SmallTestSet\DaguilarGoldCreek1_DM420157_0000m_00s__0059m_47s_49h.mp3" "C:\SensorNetworks\Software\AudioAnalysis\AnalysisConfigFiles\Towsey.MultiAnalyser.cfg" "C:\SensorNetworks\Output\Test1"
 
             // FLYING FOX RECORDINGS
-            string recordingPath = @"C:\Ecoacoustics\WavFiles\BradLawData\FlyingFox\20190127_Bellingen_Feeding_SM4.wav";
+            //string recordingPath = @"C:\Ecoacoustics\WavFiles\BradLawData\FlyingFox\20190127_Bellingen_Feeding_SM4.wav";
+            string recordingPath = @"C:\Ecoacoustics\WavFiles\BradLawData\FlyingFox\20190115_Bellingen_Feeding.wav";
             string configPath = @"C:\Work\GitHub\audio-analysis\src\AnalysisConfigFiles\RecognizerConfigFiles\Towsey.PteropusSpecies.yml";
             string outputPath = @"C:\Ecoacoustics\Output\BradLaw\FlyingFox";
 

src/AudioAnalysisTools/AcousticEvent.cs

@@ -1,4 +1,4 @@
-// --------------------------------------------------------------------------------------------------------------------
+// --------------------------------------------------------------------------------------------------------------------
 // <copyright file="AcousticEvent.cs" company="QutEcoacoustics">
 // All code in this file and all associated files are the copyright and property of the QUT Ecoacoustics Research Group (formerly MQUTeR, and formerly QUT Bioacoustics Research Group).
 // </copyright>
@@ -14,10 +14,12 @@ namespace AudioAnalysisTools
     using System.Collections.ObjectModel;
     using System.Drawing;
     using System.IO;
+    using System.Linq;
     using System.Text;
     using System.Text.RegularExpressions;
     using Acoustics.Shared.Contracts;
     using Acoustics.Shared.Csv;
+    using AForge.Imaging.Filters;
     using AnalysisBase.ResultBases;
     using CsvHelper.Configuration;
     using DSP;
@@ -1097,9 +1099,9 @@ public static List<AcousticEvent> ConvertIntensityArray2Events(
                         //obtain average intensity score.
                         double av = 0.0;
                         for (int n = startFrame; n <= i; n++)
-                    {
-                        av += values[n];
-                    }
+                        {
+                            av += values[n];
+                        }
 
                         ev.Score = av / (i - startFrame + 1);
                         events.Add(ev);
@@ -1109,6 +1111,63 @@ public static List<AcousticEvent> ConvertIntensityArray2Events(
             return events;
         }
 
+        public static List<AcousticEvent> GetEventsAroundMaxima(
+            double[] values,
+            TimeSpan segmentStartOffset,
+            int minHz,
+            int maxHz,
+            double framesPerSec,
+            double freqBinWidth,
+            double thresholdValue,
+            TimeSpan nh)
+        {
+            int count = values.Length;
+            var events = new List<AcousticEvent>();
+            double frameOffset = 1 / framesPerSec; //frame offset in fractions of second
+
+            // every event will have duration of twice the buffer + 1
+            int frameBuffer = (int)Math.Ceiling(nh.TotalSeconds / frameOffset);
+            frameBuffer = Math.Max(frameBuffer, 1);
+            int eventLength = (2 * frameBuffer) + 1;
+
+            // every event has the same duration
+            double eventDuration = eventLength * frameOffset;
+
+            //int startFrame = 0;
+
+            // for all frames
+            for (int i = frameBuffer; i < count - frameBuffer; i++)
+            {
+                // skip if value below threshold
+                if (values[i] < thresholdValue)
+                {
+                    continue;
+                }
+
+                // get the neighbourhood
+                var nhArray = DataTools.Subarray(values, i - frameBuffer, eventLength);
+                int maxId = DataTools.GetMaxIndex(nhArray);
+
+                // if middle frame is a local maximum then have an event
+                if (maxId == frameBuffer)
+                {
+                    double startTime = (i - frameBuffer) * frameOffset; // time in seconds
+                    AcousticEvent ev = new AcousticEvent(segmentStartOffset, startTime, eventDuration, minHz, maxHz)
+                    {
+                        Name = "Event", //default name
+                    };
+
+                    ev.SetTimeAndFreqScales(framesPerSec, freqBinWidth);
+
+                    //obtain average intensity score.
+                    ev.Score = nhArray.Average();
+                    events.Add(ev);
+                }
+            }
+
+            return events;
+        }
+
         /// <summary>
         /// A general method to convert an array of score values to a list of AcousticEvents.
         /// The method uses the passed scoreThreshold in order to calculate a normalised score.