<script src="https://raw.github.com/auduno/headtrackr/master/headtrackr.js"></script>
<canvas id="inputCanvas" width="320" height="240" style="display:none"></canvas>
<video id="inputVideo" autoplay loop></video>
<script type="text/javascript">
var videoInput = document.getElementById('inputVideo');
var canvasInput = document.getElementById('inputCanvas');
var htracker = new headtrackr.Tracker();
htracker.init(videoInput, canvasInput);
htracker.start();
</script>