Harden speaker identity samples

2026-05-28 12:02:44 +02:00
parent c84f8a984a
commit a72cda0c03
23 changed files with 1251 additions and 123 deletions
@@ -0,0 +1,76 @@
+using MeetingAssistant.Recording;
+using MeetingAssistant.Transcription;
+using NAudio.Wave;
+
+namespace MeetingAssistant.Tests;
+
+public sealed class SpeakerAudioSampleCollectorTests
+{
+    [Fact]
+    public void CollectorWaitsForConfiguredUninterruptedSpeechDuration()
+    {
+        var collector = new SpeakerAudioSampleCollector(
+            TimeSpan.FromMinutes(2),
+            maxSamplesPerSpeaker: 3,
+            minimumUninterruptedSpeechDuration: TimeSpan.FromSeconds(30),
+            maximumSegmentGap: TimeSpan.FromSeconds(1));
+        collector.AppendAudio(CreateAudio(TimeSpan.FromSeconds(35)));
+
+        collector.TryAdd(Segment(0, 12, "Guest01", "one two three four five."));
+        collector.TryAdd(Segment(12, 24, "Guest01", "six seven eight nine ten."));
+
+        Assert.Empty(collector.Snapshot());
+
+        collector.TryAdd(Segment(24, 31, "Guest01", "eleven twelve thirteen fourteen fifteen."));
+
+        var sample = Assert.Single(collector.Snapshot());
+        Assert.Equal("Guest01", sample.Speaker);
+        Assert.Equal(TimeSpan.Zero, sample.Segment.Start);
+        Assert.Equal(TimeSpan.FromSeconds(31), sample.Segment.End);
+        Assert.True(ReadDuration(sample.WavBytes) >= TimeSpan.FromSeconds(30));
+    }
+
+    [Fact]
+    public void CollectorDoesNotCombineSpeechAcrossDifferentSpeakerInterruption()
+    {
+        var collector = new SpeakerAudioSampleCollector(
+            TimeSpan.FromMinutes(2),
+            maxSamplesPerSpeaker: 3,
+            minimumUninterruptedSpeechDuration: TimeSpan.FromSeconds(30),
+            maximumSegmentGap: TimeSpan.FromSeconds(1));
+        collector.AppendAudio(CreateAudio(TimeSpan.FromSeconds(50)));
+
+        collector.TryAdd(Segment(0, 20, "Guest01", "one two three four five."));
+        collector.TryAdd(Segment(20, 22, "Guest02", "interrupting now."));
+        collector.TryAdd(Segment(22, 35, "Guest01", "six seven eight nine ten."));
+
+        Assert.DoesNotContain(collector.Snapshot(), sample => sample.Speaker == "Guest01");
+    }
+
+    private static TranscriptionSegment Segment(
+        double start,
+        double end,
+        string speaker,
+        string text)
+    {
+        return new TranscriptionSegment(
+            TimeSpan.FromSeconds(start),
+            TimeSpan.FromSeconds(end),
+            speaker,
+            text);
+    }
+
+    private static AudioChunk CreateAudio(TimeSpan duration)
+    {
+        const int sampleRate = 16000;
+        const int channels = 1;
+        var bytes = new byte[(int)(duration.TotalSeconds * sampleRate * channels * sizeof(short))];
+        return new AudioChunk(bytes, sampleRate, channels);
+    }
+
+    private static TimeSpan ReadDuration(byte[] wavBytes)
+    {
+        using var reader = new WaveFileReader(new MemoryStream(wavBytes));
+        return reader.TotalTime;
+    }
+}