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                <!DOCTYPE html>
<html lang="en">


  <meta charset="UTF-8">
  <title>Handtrack.js : A library for prototyping realtime handtracking in the browser. </title>
  <link rel="stylesheet" href="" />
  <link rel="stylesheet" href="track.css">

<body class="bx--body p20">
  <!-- <img id="img" src="hand.jpg"/>  -->
  <div class="p20">
    Handtrack.js allows you prototype handtracking interactions in the browser in 10 lines of code.
  <div class="mb10">
    <button onclick="toggleVideo()" id="trackbutton" class="bx--btn bx--btn--secondary" type="button">
      Toggle Video
    <div id="updatenote" class="updatenote mt10"> loading model ..</div>
  <video class="videobox canvasbox" autoplay="autoplay" id="myvideo"></video>

  <canvas id="canvas" class="border canvasbox"></canvas>

  <script src=""></script>
  <script src=""> </script>
  <script src="track.js"></script>



                body {
    padding: 20px;

.p20 {
    padding: 20px;

.canvasbox {
    border-radius: 3px;
    margin-right: 10px;
    width: 450px;
    height: 338px;
    border-bottom: 3px solid #0063FF;
    box-shadow: 0 2px 3px 0 rgba(0, 0, 0, 0.2), 0 4px 10px 0 #00000030;
  background: #333;


.mb10 {
    margin-bottom: 10px

.mt10 {
    margin-top: 10px

.updatenote {
    padding: 10px;
    background: rgb(245, 147, 20);
    color: white;
    display: inline;


                const video = document.getElementById("myvideo");
const canvas = document.getElementById("canvas");
const context = canvas.getContext("2d");
let trackButton = document.getElementById("trackbutton");
let updateNote = document.getElementById("updatenote");

let isVideo = false;
let model = null;

const modelParams = {
    flipHorizontal: true,   // flip e.g for video  
    maxNumBoxes: 20,        // maximum number of boxes to detect
    iouThreshold: 0.5,      // ioU threshold for non-max suppression
    scoreThreshold: 0.6,    // confidence threshold for predictions.

function startVideo() {
    handTrack.startVideo(video).then(function (status) {
        console.log("video started", status);
        if (status) {
            updateNote.innerText = "Video started. Now tracking"
            isVideo = true
        } else {
            updateNote.innerText = "Please enable video"

function toggleVideo() {
    if (!isVideo) {
        updateNote.innerText = "Starting video"
    } else {
        updateNote.innerText = "Stopping video"
        isVideo = false;
        updateNote.innerText = "Video stopped"

function runDetection() {
    model.detect(video).then(predictions => {
        console.log("Predictions: ", predictions);
        model.renderPredictions(predictions, canvas, context, video);
        if (isVideo) {

// Load the model.
handTrack.load(modelParams).then(lmodel => {
    // detect objects in the image.
    model = lmodel
    updateNote.innerText = "Loaded Model!"
    trackButton.disabled = false