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AlekseyMartynov · Sep 12, 2023 · bb98ce4 · bb98ce4
1 parent 6a92b03
commit bb98ce4
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Showing 2 changed files with 34 additions and 11 deletions.
diff --git a/Tagging/PeakFinder.cs b/Tagging/PeakFinder.cs
@@ -12,17 +12,18 @@ float LogMagnitude
 
 class PeakFinder {
     public const int
-        DIST_TIME = 45,
-        DIST_FREQ = 9;
+        // Refer to Tests/PeakDensityResearch.Fat()
+        H_STRIPE_DIST = 45, H_BIN_DIST = 1,
+        V_STRIPE_DIST = 3, V_BIN_DIST = 10;
 
     // Peaks per second in a band
     const int RATE = 12;
 
     static readonly IReadOnlyList<int> BAND_FREQS = new[] { 250, 520, 1450, 3500, 5500 };
 
     static readonly int
-        MIN_BIN = Math.Max(Analysis.FreqToBin(BAND_FREQS.Min()), DIST_FREQ),
-        MAX_BIN = Math.Min(Analysis.FreqToBin(BAND_FREQS.Max()), Analysis.BIN_COUNT - DIST_FREQ);
+        MIN_BIN = Math.Max(Analysis.FreqToBin(BAND_FREQS.Min()), V_BIN_DIST),
+        MAX_BIN = Math.Min(Analysis.FreqToBin(BAND_FREQS.Max()), Analysis.BIN_COUNT - V_BIN_DIST);
 
     static readonly float
         MIN_MAGN_SQUARED = 1f / 512 / 512,
@@ -42,8 +43,8 @@ public PeakFinder(Analysis analysis) {
     }
 
     void Analysis_StripeAddedCallback() {
-        if(Analysis.StripeCount > 2 * DIST_TIME)
-            Find(Analysis.StripeCount - DIST_TIME - 1);
+        if(Analysis.StripeCount > 2 * H_STRIPE_DIST)
+            Find(Analysis.StripeCount - H_STRIPE_DIST - 1);
     }
 
     void Find(int stripe) {
@@ -52,10 +53,10 @@ void Find(int stripe) {
             if(Analysis.GetMagnitudeSquared(stripe, bin) < MIN_MAGN_SQUARED)
                 continue;
 
-            if(!IsPeak(stripe, bin, DIST_TIME, 0))
+            if(!IsPeak(stripe, bin, H_STRIPE_DIST, H_BIN_DIST))
                 continue;
 
-            if(!IsPeak(stripe, bin, 3, DIST_FREQ))
+            if(!IsPeak(stripe, bin, V_STRIPE_DIST, V_BIN_DIST))
                 continue;
 
             AddPeakAt(stripe, bin);
@@ -135,15 +136,37 @@ void AddPeakAt(int stripe, int bin) {
             var capturedDuration = 1d / Analysis.CHUNKS_PER_SECOND * (stripe - bandPeaks.First().StripeIndex);
             var allowedCount = 1 + capturedDuration * RATE;
             if(bandPeaks.Count > allowedCount) {
+#if FALSE
                 var pruneIndex = bandPeaks.FindLastIndex(l => l.LogMagnitude < newPeak.LogMagnitude);
                 if(pruneIndex < 0)
                     return;
-
+#else
+                var pruneIndex = IndexOfMinLogMagnitude(bandPeaks);
+                if(newPeak.LogMagnitude <= bandPeaks[pruneIndex].LogMagnitude)
+                    return;
+#endif
                 bandPeaks.RemoveAt(pruneIndex);
             }
         }
 
         bandPeaks.Add(newPeak);
     }
 
+    static int IndexOfMinLogMagnitude(IEnumerable<PeakInfo> peaks) {
+        var minLogMagnitude = -1f;
+        var minIndex = -1;
+
+        var currIndex = 0;
+
+        foreach(var p in peaks) {
+            var currLogMagnitude = p.LogMagnitude;
+            if(minIndex < 0 || currLogMagnitude < minLogMagnitude) {
+                minLogMagnitude = currLogMagnitude;
+                minIndex = currIndex;
+            }
+            currIndex++;
+        }
+
+        return minIndex;
+    }
 }
diff --git a/Test/SignatureComparisonTests.cs b/Test/SignatureComparisonTests.cs
@@ -29,7 +29,7 @@ out var refBands
             );
 
             // Official signature has more peaks
-            // Most of them are at edges < DIST_TIME
+            // Most of them are at edges < H_STRIPE_DIST
 
             // Possible explanation for padding in official signature
             // start - first chunk completes the FFT window so it is immediately ready for analysis
@@ -63,7 +63,7 @@ out var refBands
                 refMagnList.Add(refPeak.LogMagnitude);
             }
 
-            Assert.True(1d * hitCount / myPeaks.Count > 0.75); // TODO
+            Assert.True(1d * hitCount / myPeaks.Count > 0.9);
 
             var (magnFitIntercept, magnFitSlope) = Fit.Line(myMagnList.ToArray(), refMagnList.ToArray());