Remove music button and MP3 decode, keep live capture only

- Remove Music button, OnMusic/RunMusicAsync/StopMusic and all music fields
- MusicAnalyzer: remove Analyze, DecodeToMono, MusicPattern record;
  keep ExtractFeatures/MapPitchToPeriod/BuildWaveFrame/TickFeature (used by LiveCapture)
- Remove unused NAudio.Wave and System.Diagnostics imports from MainForm
- Fix LiveCapture overlap: sliding window with 50% overlap (was dropping every other frame)
- Buttons resized to 80px (Test/Live/Pattern/Stop All)

LiveCapture.cs

@@ -91,6 +91,7 @@ public class LiveCapture : IDisposable
         var window = new FftSharp.Windows.Hanning();
         var buffer = new double[MusicAnalyzer.WindowSize];
         var tf = new MusicAnalyzer.TickFeature();
+        double[]? overlap = null; // last HopSize samples from previous window
 
         while (_running)
         {
@@ -98,10 +99,23 @@ public class LiveCapture : IDisposable
 
             lock (_bufferLock)
             {
-                if (_sampleBuffer.Count >= MusicAnalyzer.WindowSize)
+                int needed = overlap != null ? MusicAnalyzer.HopSize : MusicAnalyzer.WindowSize;
+                if (_sampleBuffer.Count >= needed)
+                {
+                    if (overlap != null)
+                    {
+                        Array.Copy(overlap, 0, buffer, 0, MusicAnalyzer.HopSize);
+                        for (int i = 0; i < MusicAnalyzer.HopSize; i++)
+                            buffer[MusicAnalyzer.HopSize + i] = _sampleBuffer.Dequeue();
+                    }
+                    else
                     {
                         for (int i = 0; i < MusicAnalyzer.WindowSize; i++)
                             buffer[i] = _sampleBuffer.Dequeue();
+                    }
+                    // Save last HopSize samples for next window's overlap
+                    overlap = new double[MusicAnalyzer.HopSize];
+                    Array.Copy(buffer, MusicAnalyzer.HopSize, overlap, 0, MusicAnalyzer.HopSize);
                     windowData = buffer;
                 }
             }

MainForm.cs

@@ -1,8 +1,6 @@
 using System.ComponentModel;
 using System.Drawing.Drawing2D;
-using System.Diagnostics;
 using NAudio.CoreAudioApi;
-using NAudio.Wave;
 
 namespace Substation;
 
@@ -48,17 +46,13 @@ public class MainForm : Form
     readonly Icon _iconHot;
     string _trayState = "";
 
-    readonly Button _btnMusic;
     readonly Button _btnLive;
     readonly Button _btnPattern;
     readonly Label _lblTrack;
     readonly Label _lblAudioDev;
     readonly ComboBox _cboAudioDev;
-    bool _isMusicRunning;
     bool _isLiveRunning;
     bool _isPatternRunning;
-    WaveOutEvent? _audioOut;
-    Stopwatch? _musicStopwatch;
     LiveCapture? _liveCapture;
 
     public MainForm(CoyoteDevice device, State state, Server server)
@@ -125,39 +119,31 @@ public class MainForm : Form
         {
             Text = "Test",
             Location = new Point(16, 96),
-            Size = new Size(68, 32)
+            Size = new Size(80, 32)
         };
         _btnTest.Click += OnTest;
 
-        _btnMusic = new Button
-        {
-            Text = "Music",
-            Location = new Point(92, 96),
-            Size = new Size(68, 32)
-        };
-        _btnMusic.Click += OnMusic;
-
         _btnLive = new Button
         {
             Text = "Live",
-            Location = new Point(168, 96),
+            Location = new Point(104, 96),
-            Size = new Size(68, 32)
+            Size = new Size(80, 32)
         };
         _btnLive.Click += OnLive;
 
         _btnPattern = new Button
         {
             Text = "Pattern",
-            Location = new Point(244, 96),
+            Location = new Point(192, 96),
-            Size = new Size(68, 32)
+            Size = new Size(80, 32)
         };
         _btnPattern.Click += OnPattern;
 
         _btnStop = new Button
         {
             Text = "Stop All",
-            Location = new Point(320, 96),
+            Location = new Point(280, 96),
-            Size = new Size(76, 32)
+            Size = new Size(80, 32)
         };
         _btnStop.Click += OnStop;
 
@@ -307,7 +293,7 @@ public class MainForm : Form
         _chkScaleB.CheckedChanged += OnLimitChanged;
         OnLimitChanged(null, EventArgs.Empty);
 
-        Controls.AddRange(new Control[] { _lblBle, _lblWs, _lblDeviceName, _txtDeviceName, _btnConnect, _chkSwap, _btnTest, _btnMusic, _btnLive, _btnPattern, _btnStop, _lblAudioDev, _cboAudioDev, _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, _btnLive, _btnPattern, _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);
@@ -475,9 +461,8 @@ public class MainForm : Form
 
     void RefreshButtonStates()
     {
-        bool busy = IsTestRunning || _isMusicRunning || _isLiveRunning || _isPatternRunning;
+        bool busy = IsTestRunning || _isLiveRunning || _isPatternRunning;
         _btnTest.Enabled = !_server.HasClient && !busy;
-        _btnMusic.Enabled = !_server.HasClient && !busy;
         _btnLive.Enabled = !_server.HasClient && !busy;
         _btnPattern.Enabled = !_server.HasClient && !busy;
         _btnStop.Enabled = true;
@@ -487,12 +472,7 @@ public class MainForm : Form
     {
         if (IsDisposed) return;
 
-        if (_isMusicRunning && _musicStopwatch != null)
+        if (_isLiveRunning)
-        {
-            var elapsed = _musicStopwatch.Elapsed;
-            _lblTrack.Text = $"Playing  {elapsed:mm\\:ss} / {_musicTotalTime:mm\\:ss}  {Path.GetFileName(_musicFilePath)}";
-        }
-        else if (_isLiveRunning)
         {
             _lblTrack.Text = "Live capture";
         }
@@ -564,7 +544,6 @@ public class MainForm : Form
 
     void OnStop(object? sender, EventArgs e)
     {
-        StopMusic();
         StopLive();
         StopPattern();
         _state.SetStrength('A', 0);
@@ -590,106 +569,6 @@ public class MainForm : Form
         _state.SwapChannels = _chkSwap.Checked;
     }
 
-    string _musicFilePath = "";
-    TimeSpan _musicTotalTime;
-
-    void OnMusic(object? sender, EventArgs e)
-    {
-        if (_isMusicRunning || _server.HasClient) return;
-
-        using var dlg = new OpenFileDialog
-        {
-            Filter = "MP3 files (*.mp3)|*.mp3|All files (*.*)|*.*",
-            Title = "Select music to drive e-stim"
-        };
-        if (dlg.ShowDialog() != DialogResult.OK) return;
-
-        _musicFilePath = dlg.FileName;
-        _musicTotalTime = TimeSpan.Zero;
-        _isMusicRunning = true;
-        _btnMusic.Enabled = false;
-        _btnTest.Enabled = false;
-        _lblTrack.Text = $"Analyzing... {Path.GetFileName(_musicFilePath)}";
-
-        var filePath = _musicFilePath;
-        Task.Run(() => RunMusicAsync(filePath));
-    }
-
-    async Task RunMusicAsync(string filePath)
-    {
-        MusicPattern? pattern = null;
-        try
-        {
-            var progress = new Progress<int>(pct =>
-            {
-                if (!IsDisposed)
-                    _lblTrack.Text = $"Analyzing... {pct}%  {Path.GetFileName(filePath)}";
-            });
-            pattern = await Task.Run(() => MusicAnalyzer.Analyze(filePath, (IProgress<int>)progress));
-        }
-        catch (Exception ex)
-        {
-            BeginInvoke(() =>
-            {
-                _lblTrack.Text = $"Analysis failed: {ex.Message}";
-                _isMusicRunning = false;
-                RefreshButtonStates();
-            });
-            return;
-        }
-
-        _musicTotalTime = pattern.Duration;
-
-        // Set a moderate strength ceiling for music
-        _state.SetStrength('A', 60);
-        _state.SetStrength('B', 60);
-
-        // Clear any existing patterns and enqueue all music frames
-        _state.Stop('A');
-        _state.Stop('B');
-        _state.EnqueueStream('A', pattern.ChannelA);
-        _state.EnqueueStream('B', pattern.ChannelB);
-
-        // Start audio playback + stopwatch simultaneously
-        try
-        {
-            var reader = new AudioFileReader(filePath);
-            _audioOut = new WaveOutEvent();
-            _audioOut.Init(reader);
-            _audioOut.PlaybackStopped += (_, _) => BeginInvoke(StopMusic);
-            _musicStopwatch = Stopwatch.StartNew();
-            _audioOut.Play();
-        }
-        catch (Exception ex)
-        {
-            Console.Error.WriteLine($"[music] playback failed: {ex.Message}");
-            _musicStopwatch = Stopwatch.StartNew();
-        }
-
-        BeginInvoke(() => _lblTrack.Text = $"Playing  00:00 / {_musicTotalTime:mm\\:ss}  {Path.GetFileName(filePath)}");
-    }
-
-    void StopMusic()
-    {
-        if (_audioOut != null)
-        {
-            try { _audioOut.Stop(); } catch { }
-            try { _audioOut.Dispose(); } catch { }
-            _audioOut = null;
-        }
-        _musicStopwatch = null;
-
-        if (_isMusicRunning)
-        {
-            _isMusicRunning = false;
-            if (!IsDisposed)
-            {
-                _lblTrack.Text = "";
-                RefreshButtonStates();
-            }
-        }
-    }
-
     void PopulateAudioDevices()
     {
         using var enumerator = new MMDeviceEnumerator();

MusicAnalyzer.cs

@@ -1,11 +1,8 @@
 using System.Numerics;
 using FftSharp;
-using NAudio.Wave;
 
 namespace Substation;
 
-public record MusicPattern(List<WaveFrame> ChannelA, List<WaveFrame> ChannelB, TimeSpan Duration);
-
 public static class MusicAnalyzer
 {
     public const int WindowSize = 2048;
@@ -15,79 +12,6 @@ public static class MusicAnalyzer
     const double RhythmLow = 20, RhythmHigh = 250;
     const double MelodyLow = 300, MelodyHigh = 4000;
 
-    public static MusicPattern Analyze(string mp3Path, IProgress<int>? progress = null)
-    {
-        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 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);
-
-        double[]? prevRhythmMag = null;
-        double maxFlux = 0;
-        double maxMelodyEnergy = 0;
-
-        // First pass: collect per-tick features
-        var tickFeatures = new List<TickFeature>(tickCount);
-        int pos = 0;
-        int fftIndex = 0;
-
-        while (pos + WindowSize <= samples.Length)
-        {
-            for (int i = 0; i < WindowSize; i++)
-                buffer[i] = samples[pos + i];
-
-            window.ApplyInPlace(buffer);
-            var spectrum = FFT.Forward(buffer);
-            var mag = FFT.Magnitude(spectrum);
-
-            var (rhythmEnergy, rhythmFlux, melodyEnergy, melodyFreq) =
-                ExtractFeatures(mag, prevRhythmMag, sampleRate);
-
-            if (rhythmFlux > maxFlux) maxFlux = rhythmFlux;
-            if (melodyEnergy > maxMelodyEnergy) maxMelodyEnergy = melodyEnergy;
-
-            prevRhythmMag = mag;
-
-            int tickIdx = fftIndex / Math.Max(1, fftsPerTick);
-            while (tickFeatures.Count <= tickIdx)
-                tickFeatures.Add(new TickFeature());
-
-            var tf = tickFeatures[tickIdx];
-            tf.RhythmFlux = Math.Max(tf.RhythmFlux, rhythmFlux);
-            tf.MelodyEnergy += melodyEnergy;
-            tf.MelodyFreqSamples.Add(melodyFreq);
-            tf.MelodyCount++;
-
-            pos += HopSize;
-            fftIndex++;
-
-            if (progress != null && fftIndex % 50 == 0)
-            {
-                var pct = (int)((double)pos / samples.Length * 100);
-                progress.Report(pct);
-            }
-        }
-
-        progress?.Report(100);
-
-        // Second pass: normalize and build WaveFrames
-        foreach (var tf in tickFeatures)
-        {
-            var (frameA, frameB) = BuildWaveFrame(tf, maxFlux, maxMelodyEnergy);
-            channelA.Add(frameA);
-            channelB.Add(frameB);
-        }
-
-        return new MusicPattern(channelA, channelB, duration);
-    }
-
     public static (double rhythmEnergy, double rhythmFlux, double melodyEnergy, double melodyFreq)
         ExtractFeatures(double[] magnitude, double[]? prevRhythmMag, int sampleRate)
     {
@@ -147,31 +71,6 @@ public static class MusicAnalyzer
         return Math.Clamp(ms, 10, 1000);
     }
 
-    static double[] DecodeToMono(string mp3Path, int sampleRate)
-    {
-        using var reader = new Mp3FileReader(mp3Path);
-        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
-        int read;
-        while ((read = resampler.Read(buffer, 0, buffer.Length)) > 0)
-        {
-            for (int i = 0; i < read; i += 2)
-            {
-                short sample = (short)(buffer[i] | (buffer[i + 1] << 8));
-                sampleList.Add(sample / 32768f);
-            }
-        }
-
-        var result = new double[sampleList.Count];
-        for (int i = 0; i < sampleList.Count; i++)
-            result[i] = sampleList[i];
-        return result;
-    }
-
     public class TickFeature
     {
         public double RhythmFlux;