From 15232560bc7667160fda228230c2c8fc30a7e7a0 Mon Sep 17 00:00:00 2001
From: Raja Subramanian <raja.gobi@tutanota.com>
Date: Thu, 23 Feb 2023 09:35:12 +0530
Subject: [PATCH] Send stream start on initial start (#1456)

A couple of other bits
1. Use request layer for sending PLI on bind and connected.
2. When adjusting for overshoot, do not adjust target unless current is
   at max. If not, it could get stuck in a lower layer in the following
   scenario
      a. Overshoot to layer 2
      b. Max layer is 1, start sending PLI
      c. Get key frame for layer 0, adjust for overshoot as we have
         something at a layer lower than max.
      d. Adjust for overshoot.
      e. Setting target to max means that current and target are equal
         and no further adjustment happens.
---
 pkg/sfu/downtrack.go       | 6 +++---
 pkg/sfu/forwarder.go       | 2 +-
 pkg/sfu/streamallocator.go | 1 +
 3 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/pkg/sfu/downtrack.go b/pkg/sfu/downtrack.go
index 33fa429a6..587e1b770 100644
--- a/pkg/sfu/downtrack.go
+++ b/pkg/sfu/downtrack.go
@@ -1593,9 +1593,9 @@ func (d *DownTrack) GetNackStats() (totalPackets uint32, totalRepeatedNACKs uint
 func (d *DownTrack) onBindAndConnected() {
 	if d.connected.Load() && d.bound.Load() && !d.bindAndConnectedOnce.Swap(true) {
 		if d.kind == webrtc.RTPCodecTypeVideo {
-			targetLayers := d.forwarder.TargetLayers()
-			if targetLayers != InvalidLayers {
-				d.receiver.SendPLI(targetLayers.Spatial, true)
+			_, layer := d.forwarder.CheckSync()
+			if layer != InvalidLayerSpatial {
+				d.receiver.SendPLI(layer, true)
 			}
 		}
 
diff --git a/pkg/sfu/forwarder.go b/pkg/sfu/forwarder.go
index c155a20b4..99bcb2848 100644
--- a/pkg/sfu/forwarder.go
+++ b/pkg/sfu/forwarder.go
@@ -1515,10 +1515,10 @@ func (f *Forwarder) getTranslationParamsVideo(extPkt *buffer.ExtPacket, layer in
 						"feed", extPkt.Packet.SSRC,
 					)
 					f.currentLayers.Spatial = layer
-					f.targetLayers.Spatial = layer
 
 					if f.currentLayers.Spatial >= f.maxLayers.Spatial || f.currentLayers.Spatial == f.maxPublishedLayer {
 						tp.isSwitchingToMaxLayer = true
+						f.targetLayers.Spatial = layer
 					}
 				}
 			}
diff --git a/pkg/sfu/streamallocator.go b/pkg/sfu/streamallocator.go
index 3885158ec..54906c964 100644
--- a/pkg/sfu/streamallocator.go
+++ b/pkg/sfu/streamallocator.go
@@ -1340,6 +1340,7 @@ func newTrack(
 		isSimulcast: isSimulcast,
 		publisherID: publisherID,
 		logger:      logger,
+		isPaused:    true,
 	}
 	t.SetPriority(0)
 	t.SetMaxLayers(downTrack.MaxLayers())