<script src="https://code.jquery.com/jquery-1.11.3.min.js"></script>
<script src="https://code.jquery.com/jquery-migrate-1.2.1.min.js"></script>
<script src="jQuery-On-Hover-Image-Inner-Zoom-Plugin-jqzoomer/jqzoomer.1.0.js"></script>

<div class="demo">
  <a href="https://raw.githubusercontent.com/echochio-tw/jQuery-On-Hover-Image-Inner-Zoom-Plugin/master/large.jpg">
    <img src="https://raw.githubusercontent.com/echochio-tw/jQuery-On-Hover-Image-Inner-Zoom-Plugin/master/small.jpg">
  </a>
</div>

<script type="text/javascript">
jQuery(document).ready(function() {
                jQuery(".demo").jqzoomer();
            });
</script>