From 9c3d441d160fe8970b4cf75fb943be96dea55c71 Mon Sep 17 00:00:00 2001
From: Marcel Battista <m0battista@gmail.com>
Date: Sun, 28 Feb 2021 23:12:03 +0000
Subject: [PATCH] removes small lags from video live streamings

---
 server/internal/gst/gst.go       |  8 ++++++--
 server/internal/webrtc/webrtc.go | 25 +++++++++++++++++++++++--
 2 files changed, 29 insertions(+), 4 deletions(-)

diff --git a/server/internal/gst/gst.go b/server/internal/gst/gst.go
index c2ed8f00..df052fa0 100644
--- a/server/internal/gst/gst.go
+++ b/server/internal/gst/gst.go
@@ -90,7 +90,7 @@ func CreateAppPipeline(codecName string, pipelineDevice string, pipelineSrc stri
 		if pipelineSrc != "" {
 			pipelineStr = fmt.Sprintf(pipelineSrc+pipelineStr, pipelineDevice)
 		} else {
-			pipelineStr = fmt.Sprintf(videoSrc+"vp8enc target-bitrate=%d cpu-used=-5 threads=4 deadline=1 error-resilient=partitions keyframe-max-dist=30 auto-alt-ref=true"+pipelineStr, pipelineDevice, fps, bitrate*1000)
+			pipelineStr = fmt.Sprintf(videoSrc+"vp8enc target-bitrate=%d cpu-used=4 end-usage=cbr threads=4 deadline=1 undershoot=95 buffer-size=%d buffer-initial-size=%d buffer-optimal-size=%d keyframe-max-dist=180 min-quantizer=3 max-quantizer=40"+pipelineStr, pipelineDevice, fps, bitrate*1000, bitrate*6, bitrate*4, bitrate*5)
 		}
 	case "VP9":
 		// https://gstreamer.freedesktop.org/documentation/vpx/vp9enc.html?gi-language=c
@@ -131,7 +131,11 @@ func CreateAppPipeline(codecName string, pipelineDevice string, pipelineSrc stri
 			return nil, err
 		}
 
-		pipelineStr = fmt.Sprintf(videoSrc+"video/x-raw,format=I420 ! x264enc threads=4 bitrate=%d byte-stream=true tune=zerolatency speed-preset=veryfast ! video/x-h264,stream-format=byte-stream"+pipelineStr, pipelineDevice, fps, bitrate)
+		vbvbuf := uint(1000)
+		if bitrate > 1000 {
+			vbvbuf = bitrate
+		}
+		pipelineStr = fmt.Sprintf(videoSrc+"video/x-raw,format=NV12 ! x264enc threads=4 bitrate=%d key-int-max=60 vbv-buf-capacity=%d byte-stream=true tune=zerolatency speed-preset=veryfast ! video/x-h264,stream-format=byte-stream"+pipelineStr, pipelineDevice, fps, bitrate, vbvbuf)
 	case "Opus":
 		// https://gstreamer.freedesktop.org/documentation/opus/opusenc.html
 		// gstreamer1.0-plugins-base
diff --git a/server/internal/webrtc/webrtc.go b/server/internal/webrtc/webrtc.go
index d688f9ca..209dc13e 100644
--- a/server/internal/webrtc/webrtc.go
+++ b/server/internal/webrtc/webrtc.go
@@ -146,11 +146,13 @@ func (manager *WebRTCManager) CreatePeer(id string, session types.Session) (stri
 			Msg("connection state has changed")
 	})
 
-	if _, err = connection.AddTrack(manager.videoTrack); err != nil {
+	rtpVideo, err := connection.AddTrack(manager.videoTrack);
+	if err != nil {
 		return "", manager.config.ICELite, manager.config.ICEServers, err
 	}
 
-	if _, err = connection.AddTrack(manager.audioTrack); err != nil {
+	rtpAudio, err := connection.AddTrack(manager.audioTrack);
+	if err != nil {
 		return "", manager.config.ICELite, manager.config.ICEServers, err
 	}
 
@@ -211,6 +213,25 @@ func (manager *WebRTCManager) CreatePeer(id string, session types.Session) (stri
 		return "", manager.config.ICELite, manager.config.ICEServers, err
 	}
 
+	go func() {
+		rtcpBuf := make([]byte, 1500)
+		for {
+			if _, _, rtcpErr := rtpVideo.Read(rtcpBuf); rtcpErr != nil {
+				return
+			}
+		}
+	}()
+
+	go func() {
+		rtcpBuf := make([]byte, 1500)
+		for {
+			if _, _, rtcpErr := rtpAudio.Read(rtcpBuf); rtcpErr != nil {
+				return
+			}
+		}
+	}()
+
+
 	return description.SDP, manager.config.ICELite, manager.config.ICEServers, nil
 }