getScreenStream(function(screenStream) {
    video.srcObject = screenStream;
});

function getScreenStream(callback) {
    if (navigator.getDisplayMedia) {
        navigator.getDisplayMedia({
            video: true
        }).then(screenStream => {
            callback(screenStream);
        });
    } else if (navigator.mediaDevices.getDisplayMedia) {
        navigator.mediaDevices.getDisplayMedia({
            video: true
        }).then(screenStream => {
            callback(screenStream);
        });
    } else {
        getScreenId(function(error, sourceId, screen_constraints) {
            navigator.mediaDevices.getUserMedia(screen_constraints).then(function(screenStream) {
                callback(screenStream);
            });
        });
    }
}

No more maintaining this extension; as of 2019. So please use at your own risk.

• https://www.webrtc-experiment.com/disclaimer/

This chrome extension simply captures content of your screen. It returns source-id to callee; and that source-id can be used as chromeMediaSourceId in WebRTC applications to capture screen's MediaStream.

Note: Following demos works only if you install chrome extension from Google WebStore.

• https://www.webrtc-experiment.com/getScreenId/
• https://www.webrtc-experiment.com/Screen-Capturing/
• https://www.webrtc-experiment.com/Pluginfree-Screen-Sharing/ (peer to peer)

1. Download ZIP
2. Windows users can use WinZip/WinRAR/7Zip however MacOSX/Linux users can use tar -zxvf desktopCapture.tar.gz to extract the archive
3. Add your own domain here at line #17
4. LocalHost users can test directly by adding unpacked extension.. via chrome://extensions/
5. Otherwise you can make ZIP of the entire directory and upload at Google dashboard

Here is how to modify allowed-domains in manifest.json file:

{
    "content_scripts": [ {
       "js": [ "content-script.js" ],
       "all_frames": true,
       "run_at": "document_end",
       "matches": ["https://www.domain.com/*"]
    }]
}

Learn more about how to publish a chrome extension in Google App Store:

• https://developer.chrome.com/webstore/publish

For additional information, click this link.

Download and link Screen-Capturing.js:

• https://github.com/muaz-khan/Chrome-Extensions/tree/master/Screen-Capturing.js

Now you can use getScreenConstraints method to capture your screen:

getScreenConstraints(function(error, screen_constraints) {
    if (error) {
        return alert(error);
    }

    navigator.getUserMedia = navigator.webkitGetUserMedia || navigator.mozGetUserMedia;
    navigator.getUserMedia({
        video: screen_constraints
    }, function(stream) {
        var video = document.querySelector('video');
        video.src = URL.createObjectURL(stream);
        video.play();
    }, function(error) {
        alert(JSON.stringify(error, null, '\t'));
    });
});

For more Screen-Capturing.js snippets/help:

• https://github.com/muaz-khan/Chrome-Extensions/tree/master/Screen-Capturing.js#how-to-use-screen-capturingjs

• https://github.com/muaz-khan/getScreenId

getScreenId | Capture Screen on Any Domain! This script is a hack used to support single chrome extension usage on any HTTPs domain.

First step, install this chrome extension:

• https://chrome.google.com/webstore/detail/screen-capturing/ajhifddimkapgcifgcodmmfdlknahffk

Now use getScreenId.js (on any HTTPs page):

<script src="https://cdn.WebRTC-Experiment.com/getScreenId.js"></script>
<video controls autoplay></video>
<script>
getScreenId(function (error, sourceId, screen_constraints) {
    navigator.getUserMedia = navigator.mozGetUserMedia || navigator.webkitGetUserMedia;
    navigator.getUserMedia(screen_constraints, function (stream) {
        document.querySelector('video').src = URL.createObjectURL(stream);
    }, function (error) {
        console.error(error);
    });
});
</script>

Chrome-Extensions are released under MIT license . Copyright (c) Muaz Khan.