🎉 live server seems to be working now

third_party/sendspin-go/internal/server/opus_encoder.go

@@ -0,0 +1,60 @@
+// ABOUTME: Opus audio encoder for bandwidth-efficient streaming
+// ABOUTME: Wraps libopus to encode PCM audio to Opus format
+package server
+
+import (
+	"fmt"
+	"log"
+
+	"gopkg.in/hraban/opus.v2"
+)
+
+// OpusEncoder wraps the Opus encoder
+type OpusEncoder struct {
+	encoder    *opus.Encoder
+	sampleRate int
+	channels   int
+	frameSize  int // samples per channel per frame
+}
+
+// NewOpusEncoder creates a new Opus encoder.
+// frameSize is in samples per channel (e.g., 960 for 20ms at 48kHz).
+func NewOpusEncoder(sampleRate, channels, frameSize int) (*OpusEncoder, error) {
+	// AppAudio mode tunes the encoder for full-bandwidth music rather than speech
+	encoder, err := opus.NewEncoder(sampleRate, channels, opus.AppAudio)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create opus encoder: %w", err)
+	}
+
+	// 128 kbps per channel — aggressive enough for transparent music quality
+	bitrate := 128000 * channels
+	if err := encoder.SetBitrate(bitrate); err != nil {
+		log.Printf("Warning: Failed to set Opus bitrate: %v", err)
+	}
+
+	return &OpusEncoder{
+		encoder:    encoder,
+		sampleRate: sampleRate,
+		channels:   channels,
+		frameSize:  frameSize,
+	}, nil
+}
+
+// Encode encodes PCM samples to Opus.
+// Input: []int16 interleaved samples; output: single Opus packet.
+func (e *OpusEncoder) Encode(pcm []int16) ([]byte, error) {
+	// Opus spec maximum packet size is 4000 bytes
+	output := make([]byte, 4000)
+
+	n, err := e.encoder.Encode(pcm, output)
+	if err != nil {
+		return nil, fmt.Errorf("opus encode failed: %w", err)
+	}
+
+	return output[:n], nil
+}
+
+// Close is a no-op; opus.Encoder has no Close method.
+func (e *OpusEncoder) Close() error {
+	return nil
+}