sync: migrate ai-operator to Gitea (2026-08-10)

internal/media/asteriskws/tone.go

@@ -0,0 +1,60 @@
+package asteriskws
+
+import (
+	"encoding/binary"
+	"math"
+	"time"
+
+	"ai-operator/internal/audio"
+	"ai-operator/internal/media"
+)
+
+func GenerateSilence(codec media.Codec, duration time.Duration, sampleRate int) []byte {
+	if duration <= 0 || sampleRate <= 0 {
+		return nil
+	}
+	switch codec {
+	case media.CodecSLIN16:
+	case media.CodecULaw:
+		samples := int(duration.Seconds() * float64(sampleRate))
+		out := make([]byte, samples)
+		for i := range out {
+			out[i] = 0xff
+		}
+		return out
+	default:
+		return nil
+	}
+	samples := int(duration.Seconds() * float64(sampleRate))
+	return make([]byte, samples*2)
+}
+
+func GenerateSineToneSLIN16(frequencyHz float64, duration time.Duration, sampleRate int, amplitude float64) []byte {
+	if frequencyHz <= 0 || duration <= 0 || sampleRate <= 0 {
+		return nil
+	}
+	if amplitude < 0 {
+		amplitude = 0
+	}
+	if amplitude > 1 {
+		amplitude = 1
+	}
+	samples := int(duration.Seconds() * float64(sampleRate))
+	out := make([]byte, samples*2)
+	for i := 0; i < samples; i++ {
+		v := int16(math.Sin(2*math.Pi*frequencyHz*float64(i)/float64(sampleRate)) * amplitude * math.MaxInt16)
+		binary.LittleEndian.PutUint16(out[i*2:], uint16(v))
+	}
+	return out
+}
+
+func GenerateSineTone(codec media.Codec, frequencyHz float64, duration time.Duration, sampleRate int, amplitude float64) []byte {
+	pcm := GenerateSineToneSLIN16(frequencyHz, duration, sampleRate, amplitude)
+	if codec == media.CodecULaw {
+		return audio.EncodeULaw(pcm)
+	}
+	if codec == media.CodecSLIN16 {
+		return pcm
+	}
+	return nil
+}