This sample code exposes a button. When clicked, the button is disabled and the user is prompted to offer a stream. The user can cause the button to be re-enabled by providing a stream (e.g., giving the page access to the local camera) and then disabling the stream (e.g., revoking that access).
<input type="button" value="Start" onclick="start()" id="startBtn"> <script> var startBtn = document.getElementById('startBtn'); function start() { navigator.getUserMedia({audio:true, video:true}, gotStream, logError); startBtn.disabled = true; } function gotStream(stream) { stream.onended = function () { startBtn.disabled = false; }; } function logError(error) { log(error.name + ": " + error.message); } </script>
This example allows people to take photos of themselves from the local video camera. Note that the forthcoming Image Capture specification may provide a simpler way to accomplish this.
<article> <style scoped> video { transform: scaleX(-1); } p { text-align: center; } </style> <h1>Snapshot Kiosk</h1> <section id="splash"> <p id="errorMessage">Loading...</p> </section> <section id="app" hidden> <p><video id="monitor" autoplay></video> <canvas id="photo"></canvas> <p><input type=button value="📷" onclick="snapshot()"> </section> <script> navigator.getUserMedia({video:true}, gotStream, noStream); var video = document.getElementById('monitor'); var canvas = document.getElementById('photo'); function gotStream(stream) { video.src = URL.createObjectURL(stream); video.onerror = function () { stream.stop(); }; stream.onended = noStream; video.onloadedmetadata = function () { canvas.width = video.videoWidth; canvas.height = video.videoHeight; document.getElementById('splash').hidden = true; document.getElementById('app').hidden = false; }; } function noStream() { document.getElementById('errorMessage').textContent = 'No camera available.'; } function snapshot() { canvas.getContext('2d').drawImage(video, 0, 0); } </script> </article>