JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://cdn.rawgit.com/eduardolundgren/tracking.js/master/build/tracking-min.js"></script>
<script src="https://cdn.rawgit.com/eduardolundgren/tracking.js/master/build/data/eye-min.js"></script>
<script src="https://cdn.rawgit.com/eduardolundgren/tracking.js/master/build/data/mouth-min.js"></script>
<script src="https://cdn.rawgit.com/eduardolundgren/tracking.js/master/build/data/face-min.js"></script>
<div class="imgContainer">
    <img id="img" src="https://c1.staticflickr.com/4/3943/15715482121_d7120a6e0b_z.jpg" />
</div>

CSS

.rect {
   
    left: -1000px;
    position: absolute;
    top: -1000px;
}
#img {
    position: absolute;
    top: 50%;
    left: 50%;
    margin: -173px 0 0 -300px;
}

JavaScript

// checkout full tutorial on attuts.com 
var img = document.getElementById('img');

var tracker = new tracking.ObjectTracker(['face']); // Based on parameter it will return an array.
tracker.setStepSize(1.7);

tracking.track('#img', tracker);

tracker.on('track', function (event) {
    event.data.forEach(function (rect) {
        draw(rect.x, rect.y, rect.width, rect.height);
    });
});

function draw(x, y, w, h) {
    var rect = document.createElement('img');
    rect.src ="https://c1.staticflickr.com/4/3943/15715482121_d7120a6e0b_z.jpg"
    document.querySelector('.imgContainer').appendChild(rect);
    rect.classList.add('rect');
    rect.style.width = w + 'px';
    rect.style.height = h + 'px';
    rect.style.left = (img.offsetLeft + x) + 'px';
    rect.style.top = (img.offsetTop + y)-40 + 'px';
};