Add signature evolution samples to SignatureComparisonTests

Tagging/PeakFinder.cs

@@ -27,12 +27,14 @@ static readonly float
         LOG_MIN_MAGN_SQUARED = MathF.Log(MIN_MAGN_SQUARED);
 
     readonly Analysis Analysis;
+    readonly bool Interpolation;
     readonly IReadOnlyList<List<PeakInfo>> Bands;
 
-    public PeakFinder(Analysis analysis) {
+    public PeakFinder(Analysis analysis, bool interpolation = true) {
         analysis.SetStripeAddedCallback(Analysis_StripeAddedCallback);
 
         Analysis = analysis;
+        Interpolation = interpolation;
 
         Bands = Enumerable.Range(0, BAND_FREQS.Count - 1)
             .Select(_ => new List<PeakInfo>())
@@ -98,6 +100,10 @@ static readonly float
     }
 
     PeakInfo CreatePeakAt(int stripe, int bin) {
+        if(!Interpolation) {
+            return new PeakInfo(stripe, bin, GetLogMagnitude(stripe, bin));
+        }
+
         // Quadratic Interpolation of Spectral Peaks
         // https://stackoverflow.com/a/59140547
         // https://ccrma.stanford.edu/~jos/sasp/Quadratic_Interpolation_Spectral_Peaks.html

Tagging/Sig.cs

@@ -120,22 +120,42 @@ static class Sig {
         using var mem = new MemoryStream(data);
         using var reader = new BinaryReader(mem);
 
-        if(reader.ReadUInt32() != 0xcafe2580)
-            throw new NotSupportedException();
+        var legacyFormat = false;
 
-        mem.Position = 7 * 4;
-        sampleRate = SampleRateFromCode(reader.ReadInt32() >> 27);
+        if(reader.ReadUInt32() != 0xcafe2580) {
+            if(reader.ReadUInt32() == 0x789abc05) {
+                legacyFormat = true;
+            } else {
+                throw new NotSupportedException();
+            }
+        }
 
-        mem.Position = 10 * 4;
-        sampleCount = reader.ReadInt32();
+        if(legacyFormat) {
+            sampleRate = 16000;
 
-        mem.Position = 14 * 4;
+            mem.Position = 21 * 4;
+            sampleCount = 2 * reader.ReadInt32();
+
+            mem.Position = 26 * 4;
+        } else {
+            mem.Position = 7 * 4;
+            sampleRate = SampleRateFromCode(reader.ReadInt32() >> 27);
+
+            mem.Position = 10 * 4;
+            sampleCount = reader.ReadInt32();
+
+            mem.Position = 14 * 4;
+        }
 
         var writableBands = new List<PeakInfo>[4];
         for(var i = 0; i < 4; i++)
             writableBands[i] = new();
 
         while(mem.Position < mem.Length) {
+            if(legacyFormat) {
+                mem.Position += 4;
+            }
+
             var fat = false;
             var bandIndex = 0;
             var header = reader.ReadInt32();
@@ -149,6 +169,11 @@ static class Sig {
             }
 
             var len = reader.ReadInt32();
+
+            if(legacyFormat) {
+                mem.Position += 3 * 4;
+            }
+
             var end = mem.Position + len;
             var stripe = 0;
 

Test/SignatureComparisonTests.cs

@@ -13,18 +13,22 @@ namespace Project.Test {
 
     public class SignatureComparisonTests {
 
-        [Fact]
-        public void Ref_SigX_10_1_3() {
+        [Theory]
+        [InlineData("10.1.3")]             // APK v13.45
+        [InlineData("7.2.0")]              // APK v8.66
+        [InlineData("6.0.4", false)]       // APK v8.3
+        [InlineData("5.1.0", false, 3)]    // APK v7.11
+        public void Ref_SigX(string version, bool interpolation = true, int bandCount = 4) {
             CreateFromFile(
                 Path.Combine(TestHelper.DATA_DIR, "test.mp3"),
+                interpolation,
                 out var mySampleCount,
                 out var myRemainingSampleCount,
                 out var myBands
             );
 
             LoadBinary(
-                // Generated using libsigx.so from Android app v13.45
-                Path.Combine(TestHelper.DATA_DIR, "test-sigx-10.1.3.bin"),
+                Path.Combine(TestHelper.DATA_DIR, $"test-sigx-{version}.bin"),
                 out var refSampleCount,
                 out var refBands
             );
@@ -37,7 +41,7 @@ public class SignatureComparisonTests {
             var myMagnList = new List<double>();
             var refMagnList = new List<double>();
 
-            var myPeaks = myBands.SelectMany(i => i).ToList();
+            var myPeaks = myBands.Take(bandCount).SelectMany(i => i).ToList();
             var refPeaks = refBands.SelectMany(i => i).ToList();
 
             //var tsvMy = ToTSV(myPeaks);
@@ -68,9 +72,9 @@ public class SignatureComparisonTests {
             Assert.True(Math.Abs(magnFitIntercept) < 10);
         }
 
-        static void CreateFromFile(string path, out int sampleCount, out int remainingSampleCount, out Bands bands) {
+        static void CreateFromFile(string path, bool interpolation, out int sampleCount, out int remainingSampleCount, out Bands bands) {
             var analysis = new Analysis();
-            var finder = new PeakFinder(analysis);
+            var finder = new PeakFinder(analysis, interpolation);
 
             using var captureHelper = new FileCaptureHelper(path);
             captureHelper.Start();