How to Implement Screen Sharing on a Website

Screen sharing is becoming a critical feature for various types of websites, from collaboration tools to customer support and remote education platforms. Implementing screen sharing involves using WebRTC (Web Real-Time Communication), a technology that allows you to share media streams (video, audio, and data) between browsers without the need for external plugins. Here’s a step-by-step guide to help you implement screen sharing on your website.

1. Set Up WebRTC

WebRTC is the technology that powers most real-time communication features, including screen sharing. To start implementing WebRTC for screen sharing, you’ll need to ensure your website has the proper environment set up.

Basic Requirements:

• A secure HTTPS connection (WebRTC only works over HTTPS for security reasons).
• Access to browser media APIs like navigator.mediaDevices.getDisplayMedia for screen capture.

Start by setting up a simple WebRTC peer connection that can transmit video and audio streams between two browsers.

2. Capture the Screen

To initiate screen sharing, you can use the getDisplayMedia method provided by WebRTC. This API allows the browser to capture the content of the user’s screen, which can then be streamed to other users.

async function startScreenShare() {
    try {
        const stream = await navigator.mediaDevices.getDisplayMedia({ video: true });
        // Use this stream to send to a WebRTC connection
    } catch (err) {
        console.error("Error sharing screen: ", err);
    }
}

3. Set Up the Peer-to-Peer Connection

Once you have access to the user’s screen content, the next step is establishing a peer-to-peer connection using WebRTC. This involves creating two-way communication between users who will share and receive the screen.

const peerConnection = new RTCPeerConnection();
peerConnection.addTrack(stream.getVideoTracks()[0]);

// Signal offer and answer over a WebSocket

4. Handling Multiple Users

For many use cases, screen sharing needs to be broadcast to multiple users at the same time. This can be done by creating a peer connection with each user and sending the screen stream to them individually. Alternatively, you can use an SFU (Selective Forwarding Unit) server, which optimizes bandwidth usage by streaming from a single source to multiple users.

Services like VideoSDK and Flashphoner can simplify this process. These platforms provide infrastructure and tools to implement more complex screen-sharing features.

5. Incorporating User Interface Elements

To enhance the user experience, you should implement basic controls, such as:

• Start and stop sharing buttons.
• An indicator showing that screen sharing is active.
• Permissions prompt to ensure the user is aware of what is being shared.

<button onclick="startScreenShare()">Start Sharing</button>
<button onclick="stopScreenShare()">Stop Sharing</button>

References:

• Video SDK: WebRTC Screen Sharing
• Metered: Add Screen Sharing to Website
• Flashphoner: Embed WebRTC Screen Sharing
• GetStream: WebRTC Basics for Screen Sharing