From 49fd332e91208555d2d1cfe47725353975cf7775 Mon Sep 17 00:00:00 2001
From: Raja Subramanian <raja.gobi@tutanota.com>
Date: Mon, 12 Feb 2024 12:14:25 +0530
Subject: [PATCH] Store first SR also as it can get reset (#2472)

---
 pkg/sfu/buffer/rtpstats_sender.go | 12 ++++++------
 pkg/sfu/downtrack.go              | 24 ++++++++++++++++++++----
 pkg/sfu/receiver.go               |  2 +-
 3 files changed, 27 insertions(+), 11 deletions(-)

diff --git a/pkg/sfu/buffer/rtpstats_sender.go b/pkg/sfu/buffer/rtpstats_sender.go
index 98b25744a..ca4415140 100644
--- a/pkg/sfu/buffer/rtpstats_sender.go
+++ b/pkg/sfu/buffer/rtpstats_sender.go
@@ -583,15 +583,15 @@ func (r *RTPStatsSender) LastReceiverReportTime() time.Time {
 	return r.lastRRTime
 }
 
-func (r *RTPStatsSender) MaybeAdjustFirstPacketTime(srData *RTCPSenderReportData, ts uint32) {
+func (r *RTPStatsSender) MaybeAdjustFirstPacketTime(srFirst *RTCPSenderReportData, srNewest *RTCPSenderReportData, ts uint32) {
 	r.lock.Lock()
 	defer r.lock.Unlock()
 
-	srDataCopy := *srData
-	if r.srFeedFirst == nil {
-		r.srFeedFirst = &srDataCopy
-	}
-	r.srFeedNewest = &srDataCopy
+	srFirstCopy := *srFirst
+	r.srFeedFirst = &srFirstCopy
+
+	srNewestCopy := *srNewest
+	r.srFeedNewest = &srNewestCopy
 
 	r.maybeAdjustFirstPacketTime(ts, uint32(r.extStartTS))
 }
diff --git a/pkg/sfu/downtrack.go b/pkg/sfu/downtrack.go
index 54a948f7a..c4deac566 100644
--- a/pkg/sfu/downtrack.go
+++ b/pkg/sfu/downtrack.go
@@ -55,7 +55,13 @@ type TrackSender interface {
 	ID() string
 	SubscriberID() livekit.ParticipantID
 	TrackInfoAvailable()
-	HandleRTCPSenderReportData(payloadType webrtc.PayloadType, isSVC bool, layer int32, srData *buffer.RTCPSenderReportData) error
+	HandleRTCPSenderReportData(
+		payloadType webrtc.PayloadType,
+		isSVC bool,
+		layer int32,
+		srFirst *buffer.RTCPSenderReportData,
+		srNewest *buffer.RTCPSenderReportData,
+	) error
 }
 
 // -------------------------------------------------------------------
@@ -1913,9 +1919,19 @@ func (d *DownTrack) sendSilentFrameOnMuteForOpus() {
 	}
 }
 
-func (d *DownTrack) HandleRTCPSenderReportData(_payloadType webrtc.PayloadType, isSVC bool, layer int32, srData *buffer.RTCPSenderReportData) error {
-	if (layer == d.forwarder.GetReferenceLayerSpatial() || (layer == 0 && isSVC)) && srData != nil {
-		d.rtpStats.MaybeAdjustFirstPacketTime(srData, srData.RTPTimestamp+uint32(d.forwarder.GetReferenceTimestampOffset()))
+func (d *DownTrack) HandleRTCPSenderReportData(
+	_payloadType webrtc.PayloadType,
+	isSVC bool,
+	layer int32,
+	srFirst *buffer.RTCPSenderReportData,
+	srNewest *buffer.RTCPSenderReportData,
+) error {
+	if (layer == d.forwarder.GetReferenceLayerSpatial() || (layer == 0 && isSVC)) && srNewest != nil {
+		d.rtpStats.MaybeAdjustFirstPacketTime(
+			srFirst,
+			srNewest,
+			srNewest.RTPTimestamp+uint32(d.forwarder.GetReferenceTimestampOffset()),
+		)
 	}
 	return nil
 }
diff --git a/pkg/sfu/receiver.go b/pkg/sfu/receiver.go
index 0eba7f48d..e33f06eb4 100644
--- a/pkg/sfu/receiver.go
+++ b/pkg/sfu/receiver.go
@@ -353,7 +353,7 @@ func (w *WebRTCReceiver) AddUpTrack(track *webrtc.TrackRemote, buff *buffer.Buff
 		w.streamTrackerManager.SetRTCPSenderReportData(layer, srFirst, srNewest)
 
 		w.downTrackSpreader.Broadcast(func(dt TrackSender) {
-			_ = dt.HandleRTCPSenderReportData(w.codec.PayloadType, w.isSVC, layer, srNewest)
+			_ = dt.HandleRTCPSenderReportData(w.codec.PayloadType, w.isSVC, layer, srFirst, srNewest)
 		})
 	})