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Any URL's added here will be added as <script>s in order, and run before the JavaScript in the editor. You can use the URL of any other Pen and it will include the JavaScript from that Pen.

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Use npm Packages

We can make npm packages available for you to use in your JavaScript. We use webpack to prepare them and make them available to import. We'll also process your JavaScript with Babel.

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HTML Settings

Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

              <button id="detect" onclick="detect()"  class="btn btn-lg btn-primary">Detect faces</button>
<img hidden id="image" crossorigin="anonymous" src="https://upload.wikimedia.org/wikipedia/commons/thumb/7/7a/Google_team_group_photo_with_Vanhanen.jpg/640px-Google_team_group_photo_with_Vanhanen.jpg"> <br>
<canvas id="canvas" width=320 height=240>

              var image = document.getElementById('image');
var canvas = document.getElementById('canvas');
var ctx = canvas.getContext("2d");
              0, 0, image.width, image.height,
              0, 0, canvas.width, canvas.height);

const scale = canvas.width / image.width;

function detect() {
  if (window.FaceDetector == undefined) {
    console.error('Face Detection not supported');
  var faceDetector = new FaceDetector();
    .then(faces => {
      // Draw the faces on the <canvas>.
      var ctx = document.getElementById('canvas').getContext("2d");
      ctx.lineWidth = 2;
      ctx.strokeStyle = "red";
      for(var i = 0; i < faces.length; i++) {
        const face = faces[i].boundingBox;
        ctx.rect(Math.floor(face.x * scale), 
                 Math.floor(face.y * scale),
                 Math.floor(face.width * scale), 
                 Math.floor(face.height * scale));

      // Add the faces as strings to the <footer>
      var footer = document.getElementsByTagName('footer')[0];
      footer.innerHTML = 
          '<p>Detected ' + faces.length + ' faces</p><ul>';
      for(var i = 0; i < faces.length; i++) {
        const face = faces[i].boundingBox;
        footer.innerHTML += 
            '<li>@ (' + face.x + ',' + face.y + '), size ' + 
            face.width + 'x' + face.height + '</li>';
      footer.innerHTML += '</ul>';
    }).catch((e) => {
      console.error("Boo, Face Detection failed: " + e);

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