From dafdc36e3eb6355b63eb8a14e127be6acf2bd34d Mon Sep 17 00:00:00 2001
From: Raja Subramanian <raja.gobi@tutanota.com>
Date: Thu, 8 Jan 2026 02:13:03 +0530
Subject: [PATCH] Add option to force simuclast codec. (#4226)

---
 pkg/rtc/mediatrack.go  | 5 +++++
 pkg/rtc/participant.go | 2 ++
 2 files changed, 7 insertions(+)

diff --git a/pkg/rtc/mediatrack.go b/pkg/rtc/mediatrack.go
index 4229b6345..cc6ad170d 100644
--- a/pkg/rtc/mediatrack.go
+++ b/pkg/rtc/mediatrack.go
@@ -97,6 +97,7 @@ type MediaTrackParams struct {
 	PreferVideoSizeFromMedia         bool
 	EnableRTPStreamRestartDetection  bool
 	UpdateTrackInfoByVideoSizeChange bool
+	ForceBackupCodecPolicySimulcast  bool
 }
 
 func NewMediaTrack(params MediaTrackParams, ti *livekit.TrackInfo) *MediaTrack {
@@ -105,6 +106,10 @@ func NewMediaTrack(params MediaTrackParams, ti *livekit.TrackInfo) *MediaTrack {
 		backupCodecPolicy: ti.BackupCodecPolicy,
 	}
 
+	if t.params.ForceBackupCodecPolicySimulcast {
+		t.backupCodecPolicy = livekit.BackupCodecPolicy_SIMULCAST
+	}
+
 	if t.backupCodecPolicy != livekit.BackupCodecPolicy_SIMULCAST && len(ti.Codecs) > 1 {
 		t.regressionTargetCodec = mime.NormalizeMimeType(ti.Codecs[1].MimeType)
 		t.params.Logger.Debugw("track enabled codec regression", "regressionCodec", t.regressionTargetCodec)
diff --git a/pkg/rtc/participant.go b/pkg/rtc/participant.go
index 2c2a08b97..1992d4015 100644
--- a/pkg/rtc/participant.go
+++ b/pkg/rtc/participant.go
@@ -222,6 +222,7 @@ type ParticipantParams struct {
 	UseSinglePeerConnection         bool
 	EnableDataTracks                bool
 	EnableRTPStreamRestartDetection bool
+	ForceBackupCodecPolicySimulcast bool
 }
 
 type ParticipantImpl struct {
@@ -3287,6 +3288,7 @@ func (p *ParticipantImpl) addMediaTrack(signalCid string, ti *livekit.TrackInfo)
 		PreferVideoSizeFromMedia:         p.params.PreferVideoSizeFromMedia,
 		EnableRTPStreamRestartDetection:  p.params.EnableRTPStreamRestartDetection,
 		UpdateTrackInfoByVideoSizeChange: p.params.UseOneShotSignallingMode,
+		ForceBackupCodecPolicySimulcast:  p.params.ForceBackupCodecPolicySimulcast,
 	}, ti)
 
 	mt.OnSubscribedMaxQualityChange(p.onSubscribedMaxQualityChange)