Add detector stability and gap tolerance controls

cmd/sdrd/main.go

@@ -316,7 +316,9 @@ func main() {
 		time.Duration(cfg.Detector.MinDurationMs)*time.Millisecond,
 		time.Duration(cfg.Detector.HoldMs)*time.Millisecond,
 		cfg.Detector.EmaAlpha,
-		cfg.Detector.HysteresisDb)
+		cfg.Detector.HysteresisDb,
+		cfg.Detector.MinStableFrames,
+		time.Duration(cfg.Detector.GapToleranceMs)*time.Millisecond)
 
 	window := fftutil.Hann(cfg.FFTSize)
 	h := newHub()
@@ -429,6 +431,10 @@ func main() {
 			detChanged := prev.Detector.ThresholdDb != next.Detector.ThresholdDb ||
 				prev.Detector.MinDurationMs != next.Detector.MinDurationMs ||
 				prev.Detector.HoldMs != next.Detector.HoldMs ||
+				prev.Detector.EmaAlpha != next.Detector.EmaAlpha ||
+				prev.Detector.HysteresisDb != next.Detector.HysteresisDb ||
+				prev.Detector.MinStableFrames != next.Detector.MinStableFrames ||
+				prev.Detector.GapToleranceMs != next.Detector.GapToleranceMs ||
 				prev.SampleRate != next.SampleRate ||
 				prev.FFTSize != next.FFTSize
 			windowChanged := prev.FFTSize != next.FFTSize
@@ -439,7 +445,9 @@ func main() {
 					time.Duration(next.Detector.MinDurationMs)*time.Millisecond,
 					time.Duration(next.Detector.HoldMs)*time.Millisecond,
 					next.Detector.EmaAlpha,
-					next.Detector.HysteresisDb)
+					next.Detector.HysteresisDb,
+					next.Detector.MinStableFrames,
+					time.Duration(next.Detector.GapToleranceMs)*time.Millisecond)
 			}
 			if windowChanged {
 				newWindow = fftutil.Hann(next.FFTSize)

config.yaml

@@ -17,6 +17,8 @@ detector:
   hold_ms: 500
   ema_alpha: 0.2
   hysteresis_db: 3
+  min_stable_frames: 3
+  gap_tolerance_ms: 500
 recorder:
   enabled: true
   min_snr_db: 10

internal/config/config.go

@@ -14,11 +14,13 @@ type Band struct {
 }
 
 type DetectorConfig struct {
-	ThresholdDb   float64 `yaml:"threshold_db" json:"threshold_db"`
-	MinDurationMs int     `yaml:"min_duration_ms" json:"min_duration_ms"`
-	HoldMs        int     `yaml:"hold_ms" json:"hold_ms"`
-	EmaAlpha      float64 `yaml:"ema_alpha" json:"ema_alpha"`
-	HysteresisDb  float64 `yaml:"hysteresis_db" json:"hysteresis_db"`
+	ThresholdDb     float64 `yaml:"threshold_db" json:"threshold_db"`
+	MinDurationMs   int     `yaml:"min_duration_ms" json:"min_duration_ms"`
+	HoldMs          int     `yaml:"hold_ms" json:"hold_ms"`
+	EmaAlpha        float64 `yaml:"ema_alpha" json:"ema_alpha"`
+	HysteresisDb    float64 `yaml:"hysteresis_db" json:"hysteresis_db"`
+	MinStableFrames int     `yaml:"min_stable_frames" json:"min_stable_frames"`
+	GapToleranceMs  int     `yaml:"gap_tolerance_ms" json:"gap_tolerance_ms"`
 }
 
 type RecorderConfig struct {
@@ -81,7 +83,7 @@ func Default() Config {
 		AGC:        false,
 		DCBlock:    false,
 		IQBalance:  false,
-		Detector:   DetectorConfig{ThresholdDb: -20, MinDurationMs: 250, HoldMs: 500, EmaAlpha: 0.2, HysteresisDb: 3},
+		Detector:   DetectorConfig{ThresholdDb: -20, MinDurationMs: 250, HoldMs: 500, EmaAlpha: 0.2, HysteresisDb: 3, MinStableFrames: 3, GapToleranceMs: 500},
 		Recorder: RecorderConfig{
 			Enabled:     false,
 			MinSNRDb:    10,
@@ -120,6 +122,12 @@ func Load(path string) (Config, error) {
 	if cfg.Detector.HoldMs <= 0 {
 		cfg.Detector.HoldMs = 500
 	}
+	if cfg.Detector.MinStableFrames <= 0 {
+		cfg.Detector.MinStableFrames = 3
+	}
+	if cfg.Detector.GapToleranceMs <= 0 {
+		cfg.Detector.GapToleranceMs = cfg.Detector.HoldMs
+	}
 	if cfg.FrameRate <= 0 {
 		cfg.FrameRate = 15
 	}

internal/detector/detector.go

@@ -22,11 +22,13 @@ type Event struct {
 }
 
 type Detector struct {
-	ThresholdDb  float64
-	MinDuration  time.Duration
-	Hold         time.Duration
-	EmaAlpha     float64
-	HysteresisDb float64
+	ThresholdDb     float64
+	MinDuration     time.Duration
+	Hold            time.Duration
+	EmaAlpha        float64
+	HysteresisDb    float64
+	MinStableFrames int
+	GapTolerance    time.Duration
 
 	binWidth   float64
 	nbins      int
@@ -38,16 +40,17 @@ type Detector struct {
 }
 
 type activeEvent struct {
-	id       int64
-	start    time.Time
-	lastSeen time.Time
-	centerHz float64
-	bwHz     float64
-	peakDb   float64
-	snrDb    float64
-	firstBin int
-	lastBin  int
-	class    *classifier.Classification
+	id         int64
+	start      time.Time
+	lastSeen   time.Time
+	centerHz   float64
+	bwHz       float64
+	peakDb     float64
+	snrDb      float64
+	firstBin   int
+	lastBin    int
+	class      *classifier.Classification
+	stableHits int
 }
 
 type Signal struct {
@@ -60,7 +63,7 @@ type Signal struct {
 	Class    *classifier.Classification `json:"class,omitempty"`
 }
 
-func New(thresholdDb float64, sampleRate int, fftSize int, minDur, hold time.Duration, emaAlpha, hysteresis float64) *Detector {
+func New(thresholdDb float64, sampleRate int, fftSize int, minDur, hold time.Duration, emaAlpha, hysteresis float64, minStable int, gapTolerance time.Duration) *Detector {
 	if minDur <= 0 {
 		minDur = 250 * time.Millisecond
 	}
@@ -73,18 +76,26 @@ func New(thresholdDb float64, sampleRate int, fftSize int, minDur, hold time.Dur
 	if hysteresis <= 0 {
 		hysteresis = 3
 	}
+	if minStable <= 0 {
+		minStable = 3
+	}
+	if gapTolerance <= 0 {
+		gapTolerance = hold
+	}
 	return &Detector{
-		ThresholdDb:  thresholdDb,
-		MinDuration:  minDur,
-		Hold:         hold,
-		EmaAlpha:     emaAlpha,
-		HysteresisDb: hysteresis,
-		binWidth:     float64(sampleRate) / float64(fftSize),
-		nbins:        fftSize,
-		sampleRate:   sampleRate,
-		ema:          make([]float64, fftSize),
-		active:       map[int64]*activeEvent{},
-		nextID:       1,
+		ThresholdDb:     thresholdDb,
+		MinDuration:     minDur,
+		Hold:            hold,
+		EmaAlpha:        emaAlpha,
+		HysteresisDb:    hysteresis,
+		MinStableFrames: minStable,
+		GapTolerance:    gapTolerance,
+		binWidth:        float64(sampleRate) / float64(fftSize),
+		nbins:           fftSize,
+		sampleRate:      sampleRate,
+		ema:             make([]float64, fftSize),
+		active:          map[int64]*activeEvent{},
+		nextID:          1,
 	}
 }
 
@@ -199,21 +210,23 @@ func (d *Detector) matchSignals(now time.Time, signals []Signal) []Event {
 			id := d.nextID
 			d.nextID++
 			d.active[id] = &activeEvent{
-				id:       id,
-				start:    now,
-				lastSeen: now,
-				centerHz: s.CenterHz,
-				bwHz:     s.BWHz,
-				peakDb:   s.PeakDb,
-				snrDb:    s.SNRDb,
-				firstBin: s.FirstBin,
-				lastBin:  s.LastBin,
-				class:    s.Class,
+				id:         id,
+				start:      now,
+				lastSeen:   now,
+				centerHz:   s.CenterHz,
+				bwHz:       s.BWHz,
+				peakDb:     s.PeakDb,
+				snrDb:      s.SNRDb,
+				firstBin:   s.FirstBin,
+				lastBin:    s.LastBin,
+				class:      s.Class,
+				stableHits: 1,
 			}
 			continue
 		}
 		used[best.id] = true
 		best.lastSeen = now
+		best.stableHits++
 		best.centerHz = (best.centerHz + s.CenterHz) / 2.0
 		if s.BWHz > best.bwHz {
 			best.bwHz = s.BWHz
@@ -242,11 +255,11 @@ func (d *Detector) matchSignals(now time.Time, signals []Signal) []Event {
 		if used[id] {
 			continue
 		}
-		if now.Sub(ev.lastSeen) < d.Hold {
+		if now.Sub(ev.lastSeen) < d.GapTolerance {
 			continue
 		}
 		duration := ev.lastSeen.Sub(ev.start)
-		if duration < d.MinDuration {
+		if duration < d.MinDuration || ev.stableHits < d.MinStableFrames {
 			delete(d.active, id)
 			continue
 		}

internal/detector/detector_test.go

@@ -6,7 +6,7 @@ import (
 )
 
 func TestDetectorCreatesEvent(t *testing.T) {
-	d := New(-10, 1000, 10, 1*time.Millisecond, 10*time.Millisecond, 0.2, 3)
+	d := New(-10, 1000, 10, 1*time.Millisecond, 10*time.Millisecond, 0.2, 3, 1, 10*time.Millisecond)
 	center := 0.0
 	spectrum := []float64{-30, -30, -30, -5, -5, -30, -30, -30, -30, -30}
 	now := time.Now()

internal/runtime/runtime.go

@@ -19,11 +19,13 @@ type ConfigUpdate struct {
 }
 
 type DetectorUpdate struct {
-	ThresholdDb  *float64 `json:"threshold_db"`
-	MinDuration  *int     `json:"min_duration_ms"`
-	HoldMs       *int     `json:"hold_ms"`
-	EmaAlpha     *float64 `json:"ema_alpha"`
-	HysteresisDb *float64 `json:"hysteresis_db"`
+	ThresholdDb     *float64 `json:"threshold_db"`
+	MinDuration     *int     `json:"min_duration_ms"`
+	HoldMs          *int     `json:"hold_ms"`
+	EmaAlpha        *float64 `json:"ema_alpha"`
+	HysteresisDb    *float64 `json:"hysteresis_db"`
+	MinStableFrames *int     `json:"min_stable_frames"`
+	GapToleranceMs  *int     `json:"gap_tolerance_ms"`
 }
 
 type SettingsUpdate struct {
@@ -129,6 +131,12 @@ func (m *Manager) ApplyConfig(update ConfigUpdate) (config.Config, error) {
 		if update.Detector.HysteresisDb != nil {
 			next.Detector.HysteresisDb = *update.Detector.HysteresisDb
 		}
+		if update.Detector.MinStableFrames != nil {
+			next.Detector.MinStableFrames = *update.Detector.MinStableFrames
+		}
+		if update.Detector.GapToleranceMs != nil {
+			next.Detector.GapToleranceMs = *update.Detector.GapToleranceMs
+		}
 	}
 	if update.Recorder != nil {
 		if update.Recorder.Enabled != nil {

web/app.js

@@ -29,6 +29,10 @@ const gainRange = qs('gainRange');
 const gainInput = qs('gainInput');
 const thresholdRange = qs('thresholdRange');
 const thresholdInput = qs('thresholdInput');
+const emaAlphaInput = qs('emaAlphaInput');
+const hysteresisInput = qs('hysteresisInput');
+const stableFramesInput = qs('stableFramesInput');
+const gapToleranceInput = qs('gapToleranceInput');
 const agcToggle = qs('agcToggle');
 const dcToggle = qs('dcToggle');
 const iqToggle = qs('iqToggle');
@@ -278,6 +282,12 @@ function applyConfigToUI(cfg) {
   gainInput.value = uiGain;
   thresholdRange.value = cfg.detector.threshold_db;
   thresholdInput.value = cfg.detector.threshold_db;
+  if (minDurationInput) minDurationInput.value = cfg.detector.min_duration_ms;
+  if (holdInput) holdInput.value = cfg.detector.hold_ms;
+  if (emaAlphaInput) emaAlphaInput.value = cfg.detector.ema_alpha ?? 0.2;
+  if (hysteresisInput) hysteresisInput.value = cfg.detector.hysteresis_db ?? 3;
+  if (stableFramesInput) stableFramesInput.value = cfg.detector.min_stable_frames ?? 3;
+  if (gapToleranceInput) gapToleranceInput.value = cfg.detector.gap_tolerance_ms ?? cfg.detector.hold_ms;
   agcToggle.checked = !!cfg.agc;
   dcToggle.checked = !!cfg.dc_block;
   iqToggle.checked = !!cfg.iq_balance;

web/index.html

@@ -173,12 +173,18 @@
                 <span>Threshold</span>
                 <div class="slider-row"><input id="thresholdRange" type="range" min="-120" max="0" step="1" class="range--warn" /><input id="thresholdInput" type="number" min="-120" max="0" step="1" class="slider-num" /><em>dB</em></div>
               </div>
+              <label class="field"><span>Min Duration (ms)</span><input id="minDurationInput" type="number" step="50" min="50" /></label>
+              <label class="field"><span>Hold (ms)</span><input id="holdInput" type="number" step="50" min="50" /></label>
               <label class="field"><span>Averaging</span>
                 <select id="avgSelect">
                   <option value="0">Off</option><option value="0.4">Fast</option>
                   <option value="0.2">Medium</option><option value="0.1">Slow</option>
                 </select>
               </label>
+              <label class="field"><span>EMA Alpha</span><input id="emaAlphaInput" type="number" step="0.05" min="0" max="1" /></label>
+              <label class="field"><span>Hysteresis (dB)</span><input id="hysteresisInput" type="number" step="1" min="0" /></label>
+              <label class="field"><span>Min Stable Frames</span><input id="stableFramesInput" type="number" step="1" min="1" /></label>
+              <label class="field"><span>Gap Tolerance (ms)</span><input id="gapToleranceInput" type="number" step="50" min="0" /></label>
               <div class="toggle-grid">
                 <label class="pill-toggle"><input id="agcToggle" type="checkbox" /><span class="pt"><span class="pk"></span></span><span class="pl">AGC</span></label>
                 <label class="pill-toggle"><input id="dcToggle" type="checkbox" /><span class="pt"><span class="pk"></span></span><span class="pl">DC Block</span></label>