Add live audio capture via WASAPI loopback

- LiveCapture.cs: real-time WASAPI loopback capture with rolling buffer
  and continuous FFT analysis, enqueues WaveFrames at ~10Hz
- MusicAnalyzer.cs: refactored ExtractFeatures/MapPitchToPeriod/BuildWaveFrame
  as public reusable methods with sampleRate parameter
- MainForm: audio device selector (defaults to system default), Live button
  starts/stops capture, Stop All stops live too
- Adaptive normalization (running max with slow decay) for live volume changes

LiveCapture.cs

@@ -0,0 +1,151 @@
+using System.Numerics;
+using FftSharp;
+using NAudio.CoreAudioApi;
+using NAudio.Wave;
+
+namespace Substation;
+
+public class LiveCapture : IDisposable
+{
+    readonly State _state;
+    readonly MMDevice _device;
+    WasapiLoopbackCapture? _capture;
+    Thread? _processThread;
+    volatile bool _running;
+
+    readonly Queue<double> _sampleBuffer = new();
+    readonly object _bufferLock = new();
+
+    double[]? _prevRhythmMag;
+    double _liveMaxFlux;
+    double _liveMaxMelodyEnergy;
+    int _sampleRate;
+    int _fftsPerTick;
+    int _fftIndexInTick;
+
+    public event Action? Stopped;
+
+    public LiveCapture(State state, MMDevice device)
+    {
+        _state = state;
+        _device = device;
+    }
+
+    public void Start()
+    {
+        _running = true;
+        _capture = new WasapiLoopbackCapture(_device);
+        _sampleRate = _capture.WaveFormat.SampleRate;
+        _fftsPerTick = Math.Max(1, (int)Math.Round(MusicAnalyzer.TickDuration * _sampleRate / MusicAnalyzer.HopSize));
+
+        _capture.DataAvailable += OnDataAvailable;
+        _capture.RecordingStopped += OnRecordingStopped;
+
+        _processThread = new Thread(ProcessLoop) { IsBackground = true, Name = "LiveCapture-FFT" };
+        _processThread.Start();
+
+        _capture.StartRecording();
+        Console.WriteLine($"[live] capture started: {_device.FriendlyName} ({_sampleRate}Hz, {_capture.WaveFormat.Channels}ch)");
+    }
+
+    public void Stop()
+    {
+        _running = false;
+        try { _capture?.StopRecording(); } catch { }
+    }
+
+    void OnDataAvailable(object? sender, WaveInEventArgs e)
+    {
+        int channels = _capture!.WaveFormat.Channels;
+        int bytesPerSample = _capture.WaveFormat.BitsPerSample / 8;
+        int frameSize = channels * bytesPerSample;
+        int sampleCount = e.BytesRecorded / frameSize;
+
+        lock (_bufferLock)
+        {
+            for (int i = 0; i < sampleCount; i++)
+            {
+                int offset = i * frameSize;
+                float left = BitConverter.ToSingle(e.Buffer, offset);
+                float right = channels >= 2
+                    ? BitConverter.ToSingle(e.Buffer, offset + bytesPerSample)
+                    : left;
+                _sampleBuffer.Enqueue((left + right) * 0.5);
+            }
+
+            // Cap buffer size to prevent memory growth if processing falls behind
+            while (_sampleBuffer.Count > _sampleRate * 2)
+                _sampleBuffer.Dequeue();
+        }
+    }
+
+    void OnRecordingStopped(object? sender, StoppedEventArgs e)
+    {
+        _running = false;
+        Stopped?.Invoke();
+        Console.WriteLine("[live] capture stopped");
+    }
+
+    void ProcessLoop()
+    {
+        var window = new FftSharp.Windows.Hanning();
+        var buffer = new double[MusicAnalyzer.WindowSize];
+        var tf = new MusicAnalyzer.TickFeature();
+
+        while (_running)
+        {
+            double[]? windowData = null;
+
+            lock (_bufferLock)
+            {
+                if (_sampleBuffer.Count >= MusicAnalyzer.WindowSize)
+                {
+                    for (int i = 0; i < MusicAnalyzer.WindowSize; i++)
+                        buffer[i] = _sampleBuffer.Dequeue();
+                    windowData = buffer;
+                }
+            }
+
+            if (windowData == null)
+            {
+                Thread.Sleep(5);
+                continue;
+            }
+
+            window.ApplyInPlace(windowData);
+            var spectrum = FFT.Forward(windowData);
+            var mag = FFT.Magnitude(spectrum);
+
+            var (rhythmEnergy, rhythmFlux, melodyEnergy, melodyFreq) =
+                MusicAnalyzer.ExtractFeatures(mag, _prevRhythmMag, _sampleRate);
+
+            _prevRhythmMag = mag;
+
+            // Adaptive normalization: running max with slow decay
+            _liveMaxFlux = Math.Max(rhythmFlux, _liveMaxFlux * 0.999);
+            _liveMaxMelodyEnergy = Math.Max(melodyEnergy, _liveMaxMelodyEnergy * 0.999);
+
+            tf.RhythmFlux = Math.Max(tf.RhythmFlux, rhythmFlux);
+            tf.MelodyEnergy += melodyEnergy;
+            tf.MelodyFreqSamples.Add(melodyFreq);
+            tf.MelodyCount++;
+            _fftIndexInTick++;
+
+            if (_fftIndexInTick >= _fftsPerTick)
+            {
+                var (frameA, frameB) = MusicAnalyzer.BuildWaveFrame(tf, _liveMaxFlux, _liveMaxMelodyEnergy);
+                _state.EnqueueStream('A', new[] { frameA });
+                _state.EnqueueStream('B', new[] { frameB });
+
+                tf = new MusicAnalyzer.TickFeature();
+                _fftIndexInTick = 0;
+            }
+        }
+    }
+
+    public void Dispose()
+    {
+        _running = false;
+        try { _capture?.Dispose(); } catch { }
+    }
+}

MainForm.cs

@@ -1,6 +1,7 @@
 using System.ComponentModel;
 using System.Drawing.Drawing2D;
 using System.Diagnostics;
+using NAudio.CoreAudioApi;
 using NAudio.Wave;
 
 namespace Substation;
@@ -48,10 +49,15 @@ public class MainForm : Form
     string _trayState = "";
 
     readonly Button _btnMusic;
+    readonly Button _btnLive;
     readonly Label _lblTrack;
+    readonly Label _lblAudioDev;
+    readonly ComboBox _cboAudioDev;
     bool _isMusicRunning;
+    bool _isLiveRunning;
     WaveOutEvent? _audioOut;
     Stopwatch? _musicStopwatch;
+    LiveCapture? _liveCapture;
 
     public MainForm(CoyoteDevice device, State state, Server server)
     {
@@ -61,7 +67,7 @@ public class MainForm : Form
         _loopCts = new CancellationTokenSource();
 
         Text = $"Substation {typeof(MainForm).Assembly.GetName().Version}";
-        ClientSize = new Size(420, 425);
+        ClientSize = new Size(420, 450);
         FormBorderStyle = FormBorderStyle.FixedSingle;
         MaximizeBox = false;
         StartPosition = FormStartPosition.CenterScreen;
@@ -117,30 +123,52 @@ public class MainForm : Form
         {
             Text = "Test",
             Location = new Point(16, 96),
-            Size = new Size(100, 32)
+            Size = new Size(80, 32)
         };
         _btnTest.Click += OnTest;
 
         _btnMusic = new Button
         {
             Text = "Music",
-            Location = new Point(130, 96),
-            Size = new Size(100, 32)
+            Location = new Point(104, 96),
+            Size = new Size(80, 32)
         };
         _btnMusic.Click += OnMusic;
 
+        _btnLive = new Button
+        {
+            Text = "Live",
+            Location = new Point(192, 96),
+            Size = new Size(80, 32)
+        };
+        _btnLive.Click += OnLive;
+
         _btnStop = new Button
         {
             Text = "Stop All",
-            Location = new Point(244, 96),
-            Size = new Size(100, 32)
+            Location = new Point(280, 96),
+            Size = new Size(80, 32)
         };
         _btnStop.Click += OnStop;
 
+        _lblAudioDev = new Label
+        {
+            Text = "Audio:",
+            Location = new Point(16, 134),
+            Size = new Size(40, 20)
+        };
+        _cboAudioDev = new ComboBox
+        {
+            DropDownStyle = ComboBoxStyle.DropDownList,
+            Location = new Point(60, 132),
+            Size = new Size(344, 22)
+        };
+        PopulateAudioDevices();
+
         _lblTrack = new Label
         {
             Text = "",
-            Location = new Point(16, 134),
+            Location = new Point(16, 158),
             Size = new Size(388, 16),
             ForeColor = Color.DimGray
         };
@@ -148,37 +176,37 @@ public class MainForm : Form
         _lblSendA = new Label
         {
             Text = "Send A",
-            Location = new Point(16, 160),
+            Location = new Point(16, 184),
             Size = new Size(48, 20),
             Font = new Font(Font.FontFamily, 9, FontStyle.Bold)
         };
         _heatA = new HeatMap(60)
         {
-            Location = new Point(72, 158),
+            Location = new Point(72, 182),
             Size = new Size(332, 22)
         };
         _lblSendB = new Label
         {
             Text = "Send B",
-            Location = new Point(16, 188),
+            Location = new Point(16, 212),
             Size = new Size(48, 20),
             Font = new Font(Font.FontFamily, 9, FontStyle.Bold)
         };
         _heatB = new HeatMap(60)
         {
-            Location = new Point(72, 186),
+            Location = new Point(72, 210),
             Size = new Size(332, 22)
         };
         _lblRecvA = new Label
         {
             Text = "Recv A",
-            Location = new Point(16, 216),
+            Location = new Point(16, 240),
             Size = new Size(48, 20),
             Font = new Font(Font.FontFamily, 9, FontStyle.Bold)
         };
         _gaugeRecvA = new ProgressBar
         {
-            Location = new Point(72, 216),
+            Location = new Point(72, 240),
             Size = new Size(332, 20),
             Minimum = 0,
             Maximum = 200,
@@ -187,13 +215,13 @@ public class MainForm : Form
         _lblRecvB = new Label
         {
             Text = "Recv B",
-            Location = new Point(16, 242),
+            Location = new Point(16, 266),
             Size = new Size(48, 20),
             Font = new Font(Font.FontFamily, 9, FontStyle.Bold)
         };
         _gaugeRecvB = new ProgressBar
         {
-            Location = new Point(72, 242),
+            Location = new Point(72, 266),
             Size = new Size(332, 20),
             Minimum = 0,
             Maximum = 200,
@@ -203,13 +231,13 @@ public class MainForm : Form
         _lblLimitA = new Label
         {
             Text = "Lim A",
-            Location = new Point(16, 274),
+            Location = new Point(16, 298),
             Size = new Size(40, 20),
             Font = new Font(Font.FontFamily, 9, FontStyle.Bold)
         };
         _limitBarA = new TrackBar
         {
-            Location = new Point(60, 270),
+            Location = new Point(60, 294),
             Size = new Size(220, 45),
             Minimum = 0,
             Maximum = 200,
@@ -221,14 +249,14 @@ public class MainForm : Form
         _lblLimitValA = new Label
         {
             Text = "30",
-            Location = new Point(286, 274),
+            Location = new Point(286, 298),
             Size = new Size(32, 20),
             TextAlign = ContentAlignment.MiddleRight
         };
         _chkScaleA = new CheckBox
         {
             Text = "Scale",
-            Location = new Point(320, 274),
+            Location = new Point(320, 298),
             Size = new Size(76, 24),
             Checked = false
         };
@@ -237,13 +265,13 @@ public class MainForm : Form
         _lblLimitB = new Label
         {
             Text = "Lim B",
-            Location = new Point(16, 322),
+            Location = new Point(16, 346),
             Size = new Size(40, 20),
             Font = new Font(Font.FontFamily, 9, FontStyle.Bold)
         };
         _limitBarB = new TrackBar
         {
-            Location = new Point(60, 318),
+            Location = new Point(60, 342),
             Size = new Size(220, 45),
             Minimum = 0,
             Maximum = 200,
@@ -255,21 +283,21 @@ public class MainForm : Form
         _lblLimitValB = new Label
         {
             Text = "30",
-            Location = new Point(286, 322),
+            Location = new Point(286, 346),
             Size = new Size(32, 20),
             TextAlign = ContentAlignment.MiddleRight
         };
         _chkScaleB = new CheckBox
         {
             Text = "Scale",
-            Location = new Point(320, 322),
+            Location = new Point(320, 346),
             Size = new Size(76, 24),
             Checked = false
         };
         _chkScaleB.CheckedChanged += OnLimitChanged;
         OnLimitChanged(null, EventArgs.Empty);
 
-        Controls.AddRange(new Control[] { _lblBle, _lblWs, _lblDeviceName, _txtDeviceName, _btnConnect, _chkSwap, _btnTest, _btnMusic, _btnStop, _lblTrack, _lblSendA, _heatA, _lblSendB, _heatB, _lblRecvA, _gaugeRecvA, _lblRecvB, _gaugeRecvB, _lblLimitA, _limitBarA, _lblLimitValA, _chkScaleA, _lblLimitB, _limitBarB, _lblLimitValB, _chkScaleB });
+        Controls.AddRange(new Control[] { _lblBle, _lblWs, _lblDeviceName, _txtDeviceName, _btnConnect, _chkSwap, _btnTest, _btnMusic, _btnLive, _btnStop, _lblAudioDev, _cboAudioDev, _lblTrack, _lblSendA, _heatA, _lblSendB, _heatB, _lblRecvA, _gaugeRecvA, _lblRecvB, _gaugeRecvB, _lblLimitA, _limitBarA, _lblLimitValA, _chkScaleA, _lblLimitB, _limitBarB, _lblLimitValB, _chkScaleB });
 
         // Tray icon — three cached variants: neutral=gray, active=gold, hot=red-orange
         _iconNeutral = CreateVoltageIcon(Color.Gray);
@@ -437,8 +465,9 @@ public class MainForm : Form
 
     void RefreshButtonStates()
     {
-        _btnTest.Enabled = !_server.HasClient && !IsTestRunning;
-        _btnMusic.Enabled = !_server.HasClient && !_isMusicRunning;
+        _btnTest.Enabled = !_server.HasClient && !IsTestRunning && !_isMusicRunning && !_isLiveRunning;
+        _btnMusic.Enabled = !_server.HasClient && !_isMusicRunning && !IsTestRunning && !_isLiveRunning;
+        _btnLive.Enabled = !_server.HasClient && !_isLiveRunning && !IsTestRunning && !_isMusicRunning;
         _btnStop.Enabled = true;
     }
 
@@ -451,6 +480,10 @@ public class MainForm : Form
             var elapsed = _musicStopwatch.Elapsed;
             _lblTrack.Text = $"Playing  {elapsed:mm\\:ss} / {_musicTotalTime:mm\\:ss}  {Path.GetFileName(_musicFilePath)}";
         }
+        else if (_isLiveRunning)
+        {
+            _lblTrack.Text = "Live capture";
+        }
 
         UpdateTrayIcon();
     }
@@ -516,6 +549,7 @@ public class MainForm : Form
     void OnStop(object? sender, EventArgs e)
     {
         StopMusic();
+        StopLive();
         _state.SetStrength('A', 0);
         _state.SetStrength('B', 0);
         _state.Stop('A');
@@ -639,6 +673,65 @@ public class MainForm : Form
         }
     }
 
+    void PopulateAudioDevices()
+    {
+        using var enumerator = new MMDeviceEnumerator();
+        var defaultDev = enumerator.GetDefaultAudioEndpoint(DataFlow.Render, Role.Console);
+        var devices = enumerator.EnumerateAudioEndPoints(DataFlow.Render, DeviceState.Active);
+
+        _cboAudioDev.Items.Clear();
+        int defaultIdx = 0;
+        for (int i = 0; i < devices.Count; i++)
+        {
+            _cboAudioDev.Items.Add(devices[i]);
+            if (devices[i].ID == defaultDev.ID)
+                defaultIdx = i;
+        }
+        _cboAudioDev.SelectedIndex = defaultIdx;
+    }
+
+    void OnLive(object? sender, EventArgs e)
+    {
+        if (_isLiveRunning || _server.HasClient) return;
+        if (_cboAudioDev.SelectedItem is not MMDevice dev) return;
+
+        _isLiveRunning = true;
+        _btnLive.Enabled = false;
+        _lblTrack.Text = "Starting live capture...";
+
+        _state.SetStrength('A', 60);
+        _state.SetStrength('B', 60);
+        _state.Stop('A');
+        _state.Stop('B');
+
+        _liveCapture = new LiveCapture(_state, dev);
+        _liveCapture.Stopped += () => BeginInvoke(StopLive);
+        _liveCapture.Start();
+
+        _lblTrack.Text = "Live capture";
+        RefreshButtonStates();
+    }
+
+    void StopLive()
+    {
+        if (_liveCapture != null)
+        {
+            try { _liveCapture.Stop(); } catch { }
+            try { _liveCapture.Dispose(); } catch { }
+            _liveCapture = null;
+        }
+
+        if (_isLiveRunning)
+        {
+            _isLiveRunning = false;
+            if (!IsDisposed)
+            {
+                _lblTrack.Text = "";
+                RefreshButtonStates();
+            }
+        }
+    }
+
     void UpdateTrayIcon()
     {
         var newState = _state.IsSignaling ? "hot"

MusicAnalyzer.cs

@@ -8,27 +8,26 @@ public record MusicPattern(List<WaveFrame> ChannelA, List<WaveFrame> ChannelB, T
 
 public static class MusicAnalyzer
 {
-    const int SampleRate = 44100;
-    const int WindowSize = 2048;
-    const int HopSize = 1024;
-    const double TickDuration = 0.1; // 100ms per e-stim frame
+    public const int WindowSize = 2048;
+    public const int HopSize = 1024;
+    public const double TickDuration = 0.1;
 
-    // Frequency band boundaries (Hz)
     const double RhythmLow = 20, RhythmHigh = 250;
     const double MelodyLow = 300, MelodyHigh = 4000;
 
     public static MusicPattern Analyze(string mp3Path, IProgress<int>? progress = null)
     {
-        var samples = DecodeToMono(mp3Path);
-        var duration = TimeSpan.FromSeconds((double)samples.Length / SampleRate);
+        const int sampleRate = 44100;
+        var samples = DecodeToMono(mp3Path, sampleRate);
+        var duration = TimeSpan.FromSeconds((double)samples.Length / sampleRate);
 
-        var tickCount = (int)Math.Ceiling((double)samples.Length / SampleRate / TickDuration);
+        var tickCount = (int)Math.Ceiling((double)samples.Length / sampleRate / TickDuration);
         var channelA = new List<WaveFrame>(tickCount);
         var channelB = new List<WaveFrame>(tickCount);
 
         var window = new FftSharp.Windows.Hanning();
         var buffer = new double[WindowSize];
-        int fftsPerTick = (int)Math.Round(TickDuration * SampleRate / HopSize);
+        int fftsPerTick = (int)Math.Round(TickDuration * sampleRate / HopSize);
 
         double[]? prevRhythmMag = null;
         double maxFlux = 0;
@@ -49,7 +48,7 @@ public static class MusicAnalyzer
             var mag = FFT.Magnitude(spectrum);
 
             var (rhythmEnergy, rhythmFlux, melodyEnergy, melodyFreq) =
-                ExtractFeatures(mag, prevRhythmMag);
+                ExtractFeatures(mag, prevRhythmMag, sampleRate);
 
             if (rhythmFlux > maxFlux) maxFlux = rhythmFlux;
             if (melodyEnergy > maxMelodyEnergy) maxMelodyEnergy = melodyEnergy;
@@ -79,57 +78,20 @@ public static class MusicAnalyzer
         progress?.Report(100);
 
         // Second pass: normalize and build WaveFrames
-        const int rhythmFreqMs = 150; // ~7Hz deep pulse
-
         foreach (var tf in tickFeatures)
         {
-            // Channel A: rhythm onset
-            double normalizedFlux = maxFlux > 0 ? tf.RhythmFlux / maxFlux : 0;
-            int onsetIntensity = (int)Math.Round(normalizedFlux * 100);
-            // Sub-tick attack/decay shape
-            var intA = new[]
-            {
-                (byte)Math.Clamp(onsetIntensity, 0, 100),
-                (byte)Math.Clamp(onsetIntensity * 6 / 10, 0, 100),
-                (byte)Math.Clamp(onsetIntensity * 3 / 10, 0, 100),
-                (byte)0
-            };
-            var freqA = Freq.Compress4(new[] { rhythmFreqMs, rhythmFreqMs, rhythmFreqMs, rhythmFreqMs });
-            channelA.Add(new WaveFrame(freqA, intA));
-
-            // Channel B: melody
-            double avgEnergy = tf.MelodyCount > 0 ? tf.MelodyEnergy / tf.MelodyCount : 0;
-            double normalizedEnergy = maxMelodyEnergy > 0 ? avgEnergy / maxMelodyEnergy : 0;
-            int melodyIntensity = (int)Math.Round(normalizedEnergy * 80); // cap at 80 for comfort
-            melodyIntensity = Math.Clamp(melodyIntensity, 0, 100);
-
-            // Weighted average dominant frequency
-            double weightedFreq = 0;
-            double totalWeight = 0;
-            foreach (var f in tf.MelodyFreqSamples)
-            {
-                weightedFreq += f * f; // weight by energy (freq already squared mag)
-                totalWeight += f;
-            }
-            double avgMelodyHz = totalWeight > 0 ? weightedFreq / totalWeight : 500;
-            int estimsMs = MapPitchToPeriod(avgMelodyHz);
-
-            var intB = new[]
-            {
-                (byte)melodyIntensity, (byte)melodyIntensity,
-                (byte)melodyIntensity, (byte)melodyIntensity
-            };
-            var freqB = Freq.Compress4(new[] { estimsMs, estimsMs, estimsMs, estimsMs });
-            channelB.Add(new WaveFrame(freqB, intB));
+            var (frameA, frameB) = BuildWaveFrame(tf, maxFlux, maxMelodyEnergy);
+            channelA.Add(frameA);
+            channelB.Add(frameB);
         }
 
         return new MusicPattern(channelA, channelB, duration);
     }
 
-    static (double rhythmEnergy, double rhythmFlux, double melodyEnergy, double melodyFreq) ExtractFeatures(
-        double[] magnitude, double[]? prevRhythmMag)
+    public static (double rhythmEnergy, double rhythmFlux, double melodyEnergy, double melodyFreq)
+        ExtractFeatures(double[] magnitude, double[]? prevRhythmMag, int sampleRate)
     {
-        double binWidth = (double)SampleRate / WindowSize;
+        double binWidth = (double)sampleRate / WindowSize;
         int rhythmLoBin = (int)(RhythmLow / binWidth);
         int rhythmHiBin = (int)(RhythmHigh / binWidth);
         int melodyLoBin = (int)(MelodyLow / binWidth);
@@ -172,7 +134,7 @@ public static class MusicAnalyzer
         return (rhythmEnergy, rhythmFlux, melodyEnergy, melodyFreq);
     }
 
-    static int MapPitchToPeriod(double hz)
+    public static int MapPitchToPeriod(double hz)
     {
         // Map melody frequency (300-4000Hz) to e-stim period (10-1000ms)
         // Logarithmic mapping: low notes → deep, high notes → buzzy
@@ -185,15 +147,15 @@ public static class MusicAnalyzer
         return Math.Clamp(ms, 10, 1000);
     }
 
-    static double[] DecodeToMono(string mp3Path)
+    static double[] DecodeToMono(string mp3Path, int sampleRate)
     {
         using var reader = new Mp3FileReader(mp3Path);
-        var format = new WaveFormat(SampleRate, 16, 1);
+        var format = new WaveFormat(sampleRate, 16, 1);
         using var resampler = new MediaFoundationResampler(reader, format);
         resampler.ResamplerQuality = 60;
 
         var sampleList = new List<float>();
-        var buffer = new byte[SampleRate * 2]; // 1s worth of 16-bit mono
+        var buffer = new byte[sampleRate * 2]; // 1s worth of 16-bit mono
         int read;
         while ((read = resampler.Read(buffer, 0, buffer.Length)) > 0)
         {
@@ -210,11 +172,51 @@ public static class MusicAnalyzer
         return result;
     }
 
-    class TickFeature
+    public class TickFeature
     {
         public double RhythmFlux;
         public double MelodyEnergy;
         public double MelodyCount;
         public readonly List<double> MelodyFreqSamples = new();
     }
+
+    public static (WaveFrame chA, WaveFrame chB) BuildWaveFrame(TickFeature tf, double maxFlux, double maxMelodyEnergy)
+    {
+        const int rhythmFreqMs = 150;
+
+        double normalizedFlux = maxFlux > 0 ? tf.RhythmFlux / maxFlux : 0;
+        int onsetIntensity = (int)Math.Round(normalizedFlux * 100);
+        var intA = new[]
+        {
+            (byte)Math.Clamp(onsetIntensity, 0, 100),
+            (byte)Math.Clamp(onsetIntensity * 6 / 10, 0, 100),
+            (byte)Math.Clamp(onsetIntensity * 3 / 10, 0, 100),
+            (byte)0
+        };
+        var freqA = Freq.Compress4(new[] { rhythmFreqMs, rhythmFreqMs, rhythmFreqMs, rhythmFreqMs });
+
+        double avgEnergy = tf.MelodyCount > 0 ? tf.MelodyEnergy / tf.MelodyCount : 0;
+        double normalizedEnergy = maxMelodyEnergy > 0 ? avgEnergy / maxMelodyEnergy : 0;
+        int melodyIntensity = (int)Math.Round(normalizedEnergy * 80);
+        melodyIntensity = Math.Clamp(melodyIntensity, 0, 100);
+
+        double weightedFreq = 0;
+        double totalWeight = 0;
+        foreach (var f in tf.MelodyFreqSamples)
+        {
+            weightedFreq += f * f;
+            totalWeight += f;
+        }
+        double avgMelodyHz = totalWeight > 0 ? weightedFreq / totalWeight : 500;
+        int estimsMs = MapPitchToPeriod(avgMelodyHz);
+
+        var intB = new[]
+        {
+            (byte)melodyIntensity, (byte)melodyIntensity,
+            (byte)melodyIntensity, (byte)melodyIntensity
+        };
+        var freqB = Freq.Compress4(new[] { estimsMs, estimsMs, estimsMs, estimsMs });
+
+        return (new WaveFrame(freqA, intA), new WaveFrame(freqB, intB));
+    }
 }