@vikasietum_tecknology/record-rtc/simple-demos/screen-recording.html

record-rtc is a library based on recordrtc library. In this forked version of the original library we have optimized the memory management. The video recording is stored in IndexDB in chunks.

<style>
    html, body {
        margin: 0!important;
        padding: 0!important;
        text-align: center;
        font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell, "Fira Sans", "Droid Sans", "Helvetica Neue", Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol";
        font-size: 1em;
    }

    video {
        width: 30%;
        border-radius: 5px;
        border: 1px solid black;
    }
</style>

<title>Screen Recording | RecordRTC</title>
<h1>Screen Recording using RecordRTC</h1>

<br>

<button id="btn-start-recording">Start Recording</button>
<button id="btn-stop-recording" disabled>Stop Recording</button>

<hr>
<video controls autoplay playsinline></video>

<script src="/RecordRTC.js"></script>
<script>
var video = document.querySelector('video');

if(!navigator.getDisplayMedia && !navigator.mediaDevices.getDisplayMedia) {
    var error = 'Your browser does NOT support the getDisplayMedia API.';
    document.querySelector('h1').innerHTML = error;

    document.querySelector('video').style.display = 'none';
    document.getElementById('btn-start-recording').style.display = 'none';
    document.getElementById('btn-stop-recording').style.display = 'none';
    throw new Error(error);
}

function invokeGetDisplayMedia(success, error) {
    var displaymediastreamconstraints = {
        video: {
            displaySurface: 'monitor', // monitor, window, application, browser
            logicalSurface: true,
            cursor: 'always' // never, always, motion
        }
    };

    // above constraints are NOT supported YET
    // that's why overriding them
    displaymediastreamconstraints = {
        video: true
    };

    if(navigator.mediaDevices.getDisplayMedia) {
        navigator.mediaDevices.getDisplayMedia(displaymediastreamconstraints).then(success).catch(error);
    }
    else {
        navigator.getDisplayMedia(displaymediastreamconstraints).then(success).catch(error);
    }
}

function captureScreen(callback) {
    invokeGetDisplayMedia(function(screen) {
        addStreamStopListener(screen, function() {
            document.getElementById('btn-stop-recording').click();
        });
        callback(screen);
    }, function(error) {
        console.error(error);
        alert('Unable to capture your screen. Please check console logs.\n' + error);
    });
}

function stopRecordingCallback() {
    video.src = video.srcObject = null;
    video.src = URL.createObjectURL(recorder.getBlob());
    
    recorder.screen.stop();
    recorder.destroy();
    recorder = null;

    document.getElementById('btn-start-recording').disabled = false;
}

var recorder; // globally accessible

document.getElementById('btn-start-recording').onclick = function() {
    this.disabled = true;
    captureScreen(function(screen) {
        video.srcObject = screen;

        recorder = RecordRTC(screen, {
            type: 'video'
        });

        recorder.startRecording();

        // release screen on stopRecording
        recorder.screen = screen;

        document.getElementById('btn-stop-recording').disabled = false;
    });
};

document.getElementById('btn-stop-recording').onclick = function() {
    this.disabled = true;
    recorder.stopRecording(stopRecordingCallback);
};

function addStreamStopListener(stream, callback) {
    stream.addEventListener('ended', function() {
        callback();
        callback = function() {};
    }, false);
    stream.addEventListener('inactive', function() {
        callback();
        callback = function() {};
    }, false);
    stream.getTracks().forEach(function(track) {
        track.addEventListener('ended', function() {
            callback();
            callback = function() {};
        }, false);
        track.addEventListener('inactive', function() {
            callback();
            callback = function() {};
        }, false);
    });
}
</script>

<br><br>

<footer style="margin-top: 20px; text-align: left;">
    <p style="padding: 5px 10px;"><b>Hints:</b> Are you using Chrome version 71? Please enable "chrome://flags/#enable-experimental-web-platform-features"</p>
    <p style="padding: 5px 10px;"><b>Browser support:</b> Firefox, Edge and Chrome &gt= 71</p>
    <div><small id="send-message"></small></div>
</footer>
<script src="https://www.webrtc-experiment.com/common.js"></script>