Send PLI in all recv examples

DTLS Keying material is slower then OpenSSL, for now just send PLI on an
interval until we improve our DTLS implementation

Resolves #204

examples/gstreamer-receive/main.go

@@ -2,11 +2,13 @@ package main
 
 import (
 	"fmt"
+	"time"
 
 	"github.com/pions/webrtc"
 	"github.com/pions/webrtc/examples/gstreamer-receive/gst"
 	"github.com/pions/webrtc/examples/util"
 	"github.com/pions/webrtc/pkg/ice"
+	"github.com/pions/webrtc/pkg/rtcp"
 )
 
 func main() {
@@ -32,6 +34,18 @@ func main() {
 	// Set a handler for when a new remote track starts, this handler creates a gstreamer pipeline
 	// for the given codec
 	peerConnection.OnTrack(func(track *webrtc.RTCTrack) {
+		// Send a PLI on an interval so that the publisher is pushing a keyframe every rtcpPLIInterval
+		// This is a temporary fix until we implement incoming RTCP events, then we would push a PLI only when a viewer requests it
+		go func() {
+			ticker := time.NewTicker(time.Second * 3)
+			for range ticker.C {
+				err := peerConnection.SendRTCP(&rtcp.PictureLossIndication{MediaSSRC: track.Ssrc})
+				if err != nil {
+					fmt.Println(err)
+				}
+			}
+		}()
+
 		codec := track.Codec
 		fmt.Printf("Track has started, of type %d: %s \n", track.PayloadType, codec.Name)
 		pipeline := gst.CreatePipeline(codec.Name)

examples/save-to-disk/main.go

@@ -2,11 +2,13 @@ package main
 
 import (
 	"fmt"
+	"time"
 
 	"github.com/pions/webrtc"
 	"github.com/pions/webrtc/examples/util"
 	"github.com/pions/webrtc/pkg/ice"
 	"github.com/pions/webrtc/pkg/media/ivfwriter"
+	"github.com/pions/webrtc/pkg/rtcp"
 )
 
 func main() {
@@ -34,6 +36,18 @@ func main() {
 	// an ivf file, since we could have multiple video tracks we provide a counter.
 	// In your application this is where you would handle/process video
 	peerConnection.OnTrack(func(track *webrtc.RTCTrack) {
+		// Send a PLI on an interval so that the publisher is pushing a keyframe every rtcpPLIInterval
+		// This is a temporary fix until we implement incoming RTCP events, then we would push a PLI only when a viewer requests it
+		go func() {
+			ticker := time.NewTicker(time.Second * 3)
+			for range ticker.C {
+				err := peerConnection.SendRTCP(&rtcp.PictureLossIndication{MediaSSRC: track.Ssrc})
+				if err != nil {
+					fmt.Println(err)
+				}
+			}
+		}()
+
 		if track.Codec.Name == webrtc.VP8 {
 			fmt.Println("Got VP8 track, saving to disk as output.ivf")
 			i, err := ivfwriter.New("output.ivf")