From 38530fcdc8a7780099ba5cfcf5be1ac6f0090b79 Mon Sep 17 00:00:00 2001
From: Till Hoffmann <till@thetillhoff.de>
Date: Thu, 2 Jul 2026 16:45:10 +0200
Subject: [PATCH 1/2] feat: register Opus codec in media-sdk opus package

Mirrors the g711/g722/dtmf pattern: an init() in the codec's own
package calls RegisterCodec so importers get the codec registered
by side-effect. Opus is registered Disabled:true (opt-in) since
SIP infrastructure interoperability varies; callers enable it via
msdk.CodecSetEnabled.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
---
 opus/codec.go | 49 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 49 insertions(+)
 create mode 100644 opus/codec.go

diff --git a/opus/codec.go b/opus/codec.go
new file mode 100644
index 0000000..2d61e11
--- /dev/null
+++ b/opus/codec.go
@@ -0,0 +1,49 @@
+// Copyright 2024 LiveKit, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//go:build cgo
+
+package opus
+
+import (
+	"github.com/livekit/protocol/logger"
+
+	media "github.com/livekit/media-sdk"
+)
+
+const SDPName = "opus/48000/2"
+
+func init() {
+	media.RegisterCodec(media.NewAudioCodec(media.CodecInfo{
+		SDPName:      SDPName,
+		SampleRate:   48000,
+		RTPClockRate: 48000,
+		RTPIsStatic:  false,
+		Priority:     10,
+		Disabled:     true,
+		FileExt:      "opus",
+	}, func(w media.PCM16Writer) media.WriteCloser[Sample] {
+		dec, err := Decode(w, 1, logger.GetLogger())
+		if err != nil {
+			return nil
+		}
+		return dec
+	}, func(w media.WriteCloser[Sample]) media.PCM16Writer {
+		enc, err := Encode(w, 1, logger.GetLogger())
+		if err != nil {
+			return nil
+		}
+		return enc
+	}))
+}

From f258116e9282afe70804355c4773ca64afad003a Mon Sep 17 00:00:00 2001
From: Till Hoffmann <till@thetillhoff.de>
Date: Fri, 3 Jul 2026 13:22:42 +0200
Subject: [PATCH 2/2] feat(opus): add EncodeWith and EncodeOptions for
 configurable encoder

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
---
 opus/opus.go | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/opus/opus.go b/opus/opus.go
index b0dfb0a..78fbcc5 100644
--- a/opus/opus.go
+++ b/opus/opus.go
@@ -64,11 +64,47 @@ func Decode(w media.PCM16Writer, targetChannels int, logger logger.Logger) (Writ
 	}, nil
 }
 
+// EncodeOptions tunes the Opus encoder. Zero values keep libopus defaults.
+type EncodeOptions struct {
+	// Bitrate is the target encoder bitrate in bits/sec (e.g. 24000). 0 = auto.
+	Bitrate int
+	// Complexity is the encoder computational complexity 1-10. 0 = default.
+	Complexity int
+	// FEC enables in-band Forward Error Correction.
+	FEC bool
+	// PacketLossPercent is the expected packet loss 0-100, used to tune FEC.
+	PacketLossPercent int
+}
+
 func Encode(w Writer, channels int, logger logger.Logger) (media.PCM16Writer, error) {
+	return EncodeWith(w, channels, EncodeOptions{}, logger)
+}
+
+func EncodeWith(w Writer, channels int, opts EncodeOptions, logger logger.Logger) (media.PCM16Writer, error) {
 	enc, err := opus.NewEncoder(w.SampleRate(), channels, opus.AppVoIP)
 	if err != nil {
 		return nil, err
 	}
+	if opts.Bitrate > 0 {
+		if err = enc.SetBitrate(opts.Bitrate); err != nil {
+			return nil, fmt.Errorf("opus set bitrate: %w", err)
+		}
+	}
+	if opts.Complexity > 0 {
+		if err = enc.SetComplexity(opts.Complexity); err != nil {
+			return nil, fmt.Errorf("opus set complexity: %w", err)
+		}
+	}
+	if opts.FEC {
+		if err = enc.SetInBandFEC(true); err != nil {
+			return nil, fmt.Errorf("opus set fec: %w", err)
+		}
+		if opts.PacketLossPercent > 0 {
+			if err = enc.SetPacketLossPerc(opts.PacketLossPercent); err != nil {
+				return nil, fmt.Errorf("opus set packet loss: %w", err)
+			}
+		}
+	}
 	return &encoder{
 		w:      w,
 		enc:    enc,