snapshot of https://github.com/pion/webrtc.git (main, 2026-09-15; blobs > 131072B omitted)

examples/quick-switch/README.md

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+# quick-switch
+quick-switch demonstrates how to quickly switch between multiple videos using WebRTC.
+Similiar to how sites like TikTok quickly swipe between videos
+
+
+<video src="https://github.com/user-attachments/assets/07f15044-3aeb-44e2-a866-14bd4258aca0" autoplay loop muted> </video>
+
+The logic in the frontend is purposefully kept as simple as possible. Making it easy to use this on any platform that supports WebRTC.
+
+In the `main.go` we have one video track, and we switch which video file is written to it.
+
+## Instructions
+
+### Download quick-switch
+This example requires you to clone the repo since it is serving static HTML.
+
+```
+git clone https://github.com/pion/webrtc.git
+cd webrtc/examples/quick-switch
+```
+
+### Create your videos
+This example expects AV1 inside a ivf container. I used the follow to encode for my demo.
+
+```
+ffmpeg -y \
+  -i $YOUR_INPUT_VIDEO \
+  -c:v libaom-av1 \
+  -usage realtime \
+  -lag-in-frames 0 \
+  -crf 30 \
+  -b:v 0 \
+  -g 15 \
+  -keyint_min 15 \
+  -sc_threshold 0 \
+  -pix_fmt yuv420p \
+  -f ivf \
+  output.ivf
+```
+
+
+### Run quick-switch
+Execute `go run *.go`
+
+### Open the Web UI
+Open [http://localhost:8080](http://localhost:8080). This will automatically start a PeerConnection.
+
+Press 'Next Video' and have fun! If you have ideas on how to make it better we would love to hear.

examples/quick-switch/index.html

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+<html>
+<!--
+		SPDX-FileCopyrightText: 2026 The Pion community <https://pion.ly>
+		SPDX-License-Identifier: MIT
+	-->
+
+<head>
+    <title>quick-switch</title>
+</head>
+
+<body>
+    <video id="video" autoplay muted playsinline width="500" height="500"></video>
+    <button id="nextVideo"> Next Video </button><br />
+</body>
+
+<script>
+    let peerConnection = new RTCPeerConnection()
+    peerConnection.addTransceiver('video', {direction: 'recvonly'})
+    peerConnection.ontrack = function (event) {
+        document.getElementById('video').srcObject = event.streams[0]
+    }
+
+    let dataChannel = peerConnection.createDataChannel('')
+    dataChannel.onopen = () => {
+        document.getElementById('nextVideo').onclick = () => {
+            dataChannel.send('')
+        }
+    }
+
+    peerConnection.createOffer()
+        .then(offer => peerConnection.setLocalDescription(offer)
+            .then(() => fetch(`/whip`, {
+                method: 'POST',
+                headers: {
+                    'Content-Type': 'application/sdp'
+                },
+                body: offer.sdp
+            }))
+        )
+        .then(res => res.text())
+        .then(res => peerConnection.setRemoteDescription({type: 'answer', sdp: res}))
+        .catch(alert)
+</script>
+
+</html>

examples/quick-switch/main.go

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+// SPDX-FileCopyrightText: 2026 The Pion community <https://pion.ly>
+// SPDX-License-Identifier: MIT
+
+//go:build !js
+
+// quick-switch demonstrates Pion WebRTC's ability to quickly switch between videos.
+package main
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+	"path/filepath"
+	"slices"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"github.com/pion/webrtc/v4"
+	"github.com/pion/webrtc/v4/pkg/media"
+	"github.com/pion/webrtc/v4/pkg/media/ivfreader"
+)
+
+// nolint: gochecknoglobals
+var (
+	tracksLock sync.RWMutex
+	tracks     []*webrtc.TrackLocalStaticSample
+
+	videoFiles     []string
+	videoFileIndex atomic.Int32
+)
+
+func nextVideo() {
+	newIndex := videoFileIndex.Load() + 1
+	if int(newIndex) >= len(videoFiles) {
+		newIndex = 0
+	}
+
+	videoFileIndex.Store(newIndex)
+}
+
+// nolint: cyclop
+func doWHIP(res http.ResponseWriter, req *http.Request) {
+	peerConnection, err := webrtc.NewPeerConnection(webrtc.Configuration{})
+	if err != nil {
+		panic(err)
+	}
+
+	peerConnection.OnDataChannel(func(d *webrtc.DataChannel) {
+		d.OnMessage(func(_ webrtc.DataChannelMessage) {
+			nextVideo()
+		})
+	})
+
+	// One Track is used for PeerConnection. All video streams are written to one Track
+	videoTrack, err := webrtc.NewTrackLocalStaticSample(webrtc.RTPCodecCapability{
+		MimeType: webrtc.MimeTypeAV1,
+	}, "video", "video")
+	if err != nil {
+		panic(err)
+	}
+
+	if _, err = peerConnection.AddTrack(videoTrack); err != nil {
+		panic(err)
+	}
+
+	tracksLock.Lock()
+	tracks = append(tracks, videoTrack)
+	tracksLock.Unlock()
+
+	// Set the handler for ICE connection state
+	// This will notify you when the peer has connected/disconnected
+	peerConnection.OnICEConnectionStateChange(func(connectionState webrtc.ICEConnectionState) {
+		fmt.Printf("ICE Connection State has changed: %s\n", connectionState.String())
+		if connectionState == webrtc.ICEConnectionStateClosed || connectionState == webrtc.ICEConnectionStateFailed {
+			if closeErr := peerConnection.Close(); closeErr != nil {
+				panic(closeErr)
+			}
+
+			tracksLock.Lock()
+			tracks = slices.DeleteFunc(tracks, func(x *webrtc.TrackLocalStaticSample) bool { return x == videoTrack })
+			tracksLock.Unlock()
+		}
+	})
+
+	offer, err := io.ReadAll(req.Body)
+	if err != nil {
+		panic(err)
+	}
+
+	if err = peerConnection.SetRemoteDescription(webrtc.SessionDescription{
+		Type: webrtc.SDPTypeOffer,
+		SDP:  string(offer),
+	}); err != nil {
+		panic(err)
+	}
+
+	// Create channel that is blocked until ICE Gathering is complete
+	gatherComplete := webrtc.GatheringCompletePromise(peerConnection)
+
+	answer, err := peerConnection.CreateAnswer(nil)
+	if err != nil {
+		panic(err)
+	} else if err = peerConnection.SetLocalDescription(answer); err != nil {
+		panic(err)
+	}
+
+	// Block until ICE Gathering is complete, disabling trickle ICE
+	// we do this because we only can exchange one signaling message
+	// in a production application you should exchange ICE Candidates via OnICECandidate
+	<-gatherComplete
+
+	res.Header().Set("Content-Type", "application/sdp")
+	if _, err := res.Write([]byte(peerConnection.LocalDescription().SDP)); err != nil {
+		panic(err)
+	}
+}
+
+func playFile(fileIndex int32) {
+	file, err := os.Open(videoFiles[fileIndex])
+	if err != nil {
+		panic(err)
+	}
+	defer file.Close() // nolint: errcheck
+
+	ivf, header, err := ivfreader.NewWith(file)
+	if err != nil {
+		panic(err)
+	}
+
+	frameDuration := time.Duration(header.TimebaseNumerator) * time.Second / time.Duration(header.TimebaseDenominator)
+	ticker := time.NewTicker(frameDuration)
+	defer ticker.Stop()
+
+	for {
+		if fileIndex != videoFileIndex.Load() {
+			return
+		}
+
+		frame, _, err := ivf.ParseNextFrame()
+		if errors.Is(err, io.EOF) {
+			nextVideo()
+
+			return
+		} else if err != nil {
+			panic(err)
+		}
+
+		tracksLock.RLock()
+		for _, t := range tracks {
+			if err = t.WriteSample(media.Sample{Data: frame, Duration: frameDuration}); err != nil {
+				tracksLock.RUnlock()
+				panic(err)
+			}
+		}
+		tracksLock.RUnlock()
+		<-ticker.C
+	}
+}
+
+func main() {
+	http.Handle("/", http.FileServer(http.Dir(".")))
+	http.HandleFunc("/whip", doWHIP)
+
+	// Switch between all ivf files in current directory
+	go func() {
+		files, err := filepath.Glob("*.ivf")
+		if err != nil {
+			panic(err)
+		}
+		for _, p := range files {
+			videoFiles = append(videoFiles, filepath.Base(p))
+		}
+		if len(videoFiles) == 0 {
+			panic("no .ivf files found in the working directory")
+		}
+
+		for {
+			playFile(videoFileIndex.Load())
+		}
+	}()
+
+	fmt.Println("Open http://localhost:8080 to access this demo")
+	// nolint: gosec
+	panic(http.ListenAndServe(":8080", nil))
+}