From 6df1e68a5fac7be6f1dd91f22cd7a20ac43afa5b Mon Sep 17 00:00:00 2001
From: Alex X <alexey.khit@gmail.com>
Date: Tue, 22 Apr 2025 10:26:00 +0300
Subject: [PATCH] Update wyoming producer and backchannel

---
 pkg/pcm/pcm.go             |  1 +
 pkg/wyoming/backchannel.go | 23 ++++++++++++++++++++++-
 pkg/wyoming/producer.go    | 22 ++++++++++++++++++++++
 pkg/wyoming/wyoming.go     | 20 ++------------------
 4 files changed, 47 insertions(+), 19 deletions(-)

diff --git a/pkg/pcm/pcm.go b/pkg/pcm/pcm.go
index bf54a6cf..13405ad4 100644
--- a/pkg/pcm/pcm.go
+++ b/pkg/pcm/pcm.go
@@ -203,5 +203,6 @@ func ProducerCodecs() []*core.Codec {
 		{Name: core.CodecPCM, ClockRate: 8000},
 		{Name: core.CodecPCMA, ClockRate: 8000},
 		{Name: core.CodecPCMU, ClockRate: 8000},
+		{Name: core.CodecPCML, ClockRate: 22050}, // wyoming-snd-external
 	}
 }
diff --git a/pkg/wyoming/backchannel.go b/pkg/wyoming/backchannel.go
index 8760789e..b4167ff1 100644
--- a/pkg/wyoming/backchannel.go
+++ b/pkg/wyoming/backchannel.go
@@ -2,6 +2,7 @@ package wyoming
 
 import (
 	"fmt"
+	"net"
 	"time"
 
 	"github.com/AlexxIT/go2rtc/pkg/core"
@@ -13,6 +14,26 @@ type Backchannel struct {
 	api *API
 }
 
+func newBackchannel(conn net.Conn) *Backchannel {
+	return &Backchannel{
+		core.Connection{
+			ID:         core.NewID(),
+			FormatName: "wyoming",
+			Medias: []*core.Media{
+				{
+					Kind:      core.KindAudio,
+					Direction: core.DirectionSendonly,
+					Codecs: []*core.Codec{
+						{Name: core.CodecPCML, ClockRate: 22050},
+					},
+				},
+			},
+			Transport: conn,
+		},
+		NewAPI(conn),
+	}
+}
+
 func (b *Backchannel) GetTrack(media *core.Media, codec *core.Codec) (*core.Receiver, error) {
 	return nil, core.ErrCantGetTrack
 }
@@ -23,7 +44,7 @@ func (b *Backchannel) AddTrack(media *core.Media, codec *core.Codec, track *core
 		ts := time.Now().Nanosecond()
 		evt := &Event{
 			Type:    "audio-chunk",
-			Data:    []byte(fmt.Sprintf(`{"rate":16000,"width":2,"channels":1,"timestamp":%d}`, ts)),
+			Data:    []byte(fmt.Sprintf(`{"rate":22050,"width":2,"channels":1,"timestamp":%d}`, ts)),
 			Payload: pkt.Payload,
 		}
 		_ = b.api.WriteEvent(evt)
diff --git a/pkg/wyoming/producer.go b/pkg/wyoming/producer.go
index 9cd6abb6..09451333 100644
--- a/pkg/wyoming/producer.go
+++ b/pkg/wyoming/producer.go
@@ -1,6 +1,8 @@
 package wyoming
 
 import (
+	"net"
+
 	"github.com/AlexxIT/go2rtc/pkg/core"
 	"github.com/pion/rtp"
 )
@@ -10,6 +12,26 @@ type Producer struct {
 	api *API
 }
 
+func newProducer(conn net.Conn) *Producer {
+	return &Producer{
+		core.Connection{
+			ID:         core.NewID(),
+			FormatName: "wyoming",
+			Medias: []*core.Media{
+				{
+					Kind:      core.KindAudio,
+					Direction: core.DirectionRecvonly,
+					Codecs: []*core.Codec{
+						{Name: core.CodecPCML, ClockRate: 16000},
+					},
+				},
+			},
+			Transport: conn,
+		},
+		NewAPI(conn),
+	}
+}
+
 func (p *Producer) Start() error {
 	var seq uint16
 	var ts uint32
diff --git a/pkg/wyoming/wyoming.go b/pkg/wyoming/wyoming.go
index 96d1dc5e..0c8eebae 100644
--- a/pkg/wyoming/wyoming.go
+++ b/pkg/wyoming/wyoming.go
@@ -18,25 +18,9 @@ func Dial(rawURL string) (core.Producer, error) {
 		return nil, err
 	}
 
-	cc := core.Connection{
-		ID:         core.NewID(),
-		FormatName: "wyoming",
-		Medias: []*core.Media{
-			{
-				Kind: core.KindAudio,
-				Codecs: []*core.Codec{
-					{Name: core.CodecPCML, ClockRate: 16000},
-				},
-			},
-		},
-		Transport: conn,
-	}
-
 	if u.Query().Get("backchannel") != "1" {
-		cc.Medias[0].Direction = core.DirectionRecvonly
-		return &Producer{cc, NewAPI(conn)}, nil
+		return newProducer(conn), nil
 	} else {
-		cc.Medias[0].Direction = core.DirectionSendonly
-		return &Backchannel{cc, NewAPI(conn)}, nil
+		return newBackchannel(conn), nil
 	}
 }