demo/camera.html

<!DOCTYPE html>
<html>
    <head>
        <meta charset="UTF-8" />
        <meta name="viewport" content="width=device-width, initial-scale=1.0" />
        <meta http-equiv="X-UA-Compatible" content="ie=edge" />
        <title>QrcodeDecoder - Camera</title>
    </head>
    <body>
        <button id="start">Start</button> <button id="stop">Stop</button><br />
        <span id="result">Click start to scan qrcode.</span><br />
        <hr />
        <video id="video" autoplay></video>

        <script src="./lib/vconsole.min.js"></script>
        <script src="./index.aio.min.js"></script>
        <script type="text/javascript">
            var vConsole = new VConsole();
            console.log("Hello world");
            function main() {
                var qr = new QrcodeDecoder();
                var video = document.querySelector("#video");
                var start = document.querySelector("#start");
                var stop = document.querySelector("#stop");
                var result = document.querySelector("#result");
                async function startScan() {
                    if (!qr.isCanvasSupported()) {
                        alert("Your browser doesn't match the required specs.");
                        throw new Error("Canvas and getUserMedia are required");
                    }

                    let code = await qr.decodeFromCamera(video);
                    console.log("code", code);
                    result.innerText = "Result: " + code.data;
                }
                start.onclick = startScan;

                stop.onclick = function() {
                    qr.stop();
                };
            }
            main();
        </script>
    </body>
</html>