horn limits and such

pi/roverd/config.go

@@ -66,13 +66,14 @@ type AudioConfig struct {
 }
 
 type HornConfig struct {
-	Enabled    bool    `yaml:"enabled" json:"enabled"`
-	Volume     float64 `yaml:"volume" json:"-"`
-	SampleRate int     `yaml:"sampleRate" json:"-"`
-	Channels   int     `yaml:"channels" json:"-"`
-	Device     string  `yaml:"device" json:"-"`
-	SineGain   float64 `yaml:"sineGain" json:"-"`
-	SawGain    float64 `yaml:"sawGain" json:"-"`
+	Enabled     bool     `yaml:"enabled" json:"enabled"`
+	Volume      float64  `yaml:"volume" json:"-"`
+	SampleRate  int      `yaml:"sampleRate" json:"-"`
+	Channels    int      `yaml:"channels" json:"-"`
+	Device      string   `yaml:"device" json:"-"`
+	SineGain    float64  `yaml:"sineGain" json:"-"`
+	SawGain     float64  `yaml:"sawGain" json:"-"`
+	MaxDuration Duration `yaml:"maxDuration" json:"-"`
 }
 
 type MediaConfig struct {
@@ -172,12 +173,13 @@ func LoadConfig(path string) (*Config, error) {
 			DefaultPitch:   50,
 		},
 		Horn: HornConfig{
-			Enabled:    false,
-			Volume:     0.25,
-			SampleRate: 48000,
-			Channels:   1,
-			SineGain:   1.0,
-			SawGain:    0.7,
+			Enabled:     false,
+			Volume:      0.25,
+			SampleRate:  48000,
+			Channels:    1,
+			SineGain:    1.0,
+			SawGain:     0.7,
+			MaxDuration: Duration{Duration: 1200 * time.Millisecond},
 		},
 		NightVision: NightVisionConfig{
 			Enabled:   true,
@@ -330,6 +332,9 @@ func validateHornConfig(cfg *HornConfig) {
 	if cfg.SawGain <= 0 {
 		cfg.SawGain = 0.7
 	}
+	if cfg.MaxDuration.Duration <= 0 {
+		cfg.MaxDuration = Duration{Duration: 1200 * time.Millisecond}
+	}
 }
 
 func validateNightVisionConfig(cfg *NightVisionConfig) error {

pi/roverd/horn.go

@@ -135,7 +135,11 @@ func (h *HornSynth) run(waveform string, freqs []float64, stop <-chan struct{})
 	h.mu.Unlock()
 
 	writer := bufio.NewWriterSize(stdin, 32*1024)
-	if err := h.synthLoop(writer, waveform, freqs, rate, channels, volume, stop); err != nil {
+	maxFrames := 0
+	if h.cfg.MaxDuration.Duration > 0 {
+		maxFrames = int(float64(rate) * h.cfg.MaxDuration.Duration.Seconds())
+	}
+	if err := h.synthLoop(writer, waveform, freqs, rate, channels, volume, maxFrames, stop); err != nil {
 		h.log.Printf("horn: synth failed: %v", err)
 	}
 	_ = writer.Flush()
@@ -151,7 +155,7 @@ func (h *HornSynth) run(waveform string, freqs []float64, stop <-chan struct{})
 	h.mu.Unlock()
 }
 
-func (h *HornSynth) synthLoop(writer *bufio.Writer, waveform string, freqs []float64, rate, channels int, volume float64, stop <-chan struct{}) error {
+func (h *HornSynth) synthLoop(writer *bufio.Writer, waveform string, freqs []float64, rate, channels int, volume float64, maxFrames int, stop <-chan struct{}) error {
 	phase := make([]float64, len(freqs))
 	increment := make([]float64, len(freqs))
 	for i, f := range freqs {
@@ -182,6 +186,10 @@ func (h *HornSynth) synthLoop(writer *bufio.Writer, waveform string, freqs []flo
 			}
 		}
 		for i := 0; i < framesPerChunk; i++ {
+			if maxFrames > 0 && sampleIndex >= maxFrames && !stopRequested {
+				stopRequested = true
+				releaseStart = sampleIndex
+			}
 			env := 1.0
 			if attackFrames > 0 && sampleIndex < attackFrames {
 				env = float64(sampleIndex) / float64(attackFrames)

pi/roverd/roverd.sample.yaml

@@ -52,6 +52,7 @@ horn:
   channels: 1
   sineGain: 1.0
   sawGain: 0.7
+  maxDuration: 1.2s
 nightVision:
   enabled: true
   gpioPin: 22