camera.html

<!DOCTYPE html>
<html>

<head>
    <meta charset="utf-8">
    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.1/css/bootstrap.min.css">
    <title>My Web Cam</title>

    <style>
        body {
            font-family: Arial, Helvetica, sans-serif;
            width: 1000px;
            margin: 10px;
            overflow-x: hidden;
            padding: 10px;
        }

        .btn {
            min-width: 150px;
            margin: 5px 2px;
            background-color: #3340f3;
            color: #fff;
            border-radius: 2px;
        }
    </style>
</head>

<body>

    <div class="row" style="border: 1px #000 solid;">

        <div class="col-lg-5">
            <div class="container">
                <video autoplay="true" id="camera" width="320" height="240"></video>
            </div>
        </div>

        <div class="col-lg-2">
            <input class="btn" type="button" id="btnStart" onclick="StartCamera();" value="Start Camera">
            <input class="btn" type="button" onclick="snapshot();" value="Click Image">
            <input class="btn" type="button" onclick="download();" value="Download Image">
        </div>

        <div class="col-lg-5">
            <div class="container">
                <canvas id="myCanvas" width="320" height="240"></canvas>
            </div>
        </div>
    </div>

    <script>
        var video = document.getElementById("camera");
        var canvas = document.getElementById("myCanvas");
        var camera = false;
        let currentStream = null;
        var capturedImage = false;
        var btnStart = document.getElementById("btnStart");
        var ctx = canvas.getContext('2d');


        function TurnOnCamera() {
            // Turn on the camera upon loading the page
            if (!camera) {
                if (navigator.mediaDevices.getUserMedia) {
                    navigator.mediaDevices.getUserMedia({
                        video: true
                    }).then(function (stream) {
                        currentStream = stream;
                        video.srcObject = currentStream;
                        video.style.display = 'block';
                        camera = true;
                        ;
                    }).catch(function (err) {
                        console.log(err);
                    });
                }
            }
        }

        function snapshot() {   
            if (camera) {
                ctx.drawImage(video, 0, 0, canvas.width, canvas.height);
                capturedImage = true;

                //store the things to the db now
                //reroute to the next page
            } else {
                window.alert('Please start the camera');
            }
        }

        function download() {
            if (capturedImage) {
                var link = document.createElement('a');
                link.download = 'Capture' + (Math.floor(Date.now() / 1000)) + '.jpg';
                link.href = document.getElementById('myCanvas').toDataURL('image/jpeg');
                link.click();
            } else {
                window.alert('Please capture an image to download it');
            }
        }
    </script>

</body>

</html>