Source

<script type="text/javascript">
    //<![CDATA[
    $(function(){
        $('#<?php echo $galleryId ?> a.overlay').overlay({
            expose: '#f1f1f1',
            target: '#gallery_overlay_<?php echo $galleryId ?>'
        }).gallery({
            speed: 400
        });
    });
    //]]>
</script>

<!-- overlay elements -->
<div id="gallery_overlay_<?php echo $galleryId ?>" class="gallery_overlay">
    <a class="prev">prev</a>
    <a class="next">next</a>
    <div class="info"></div>
    <img class="progress" src="/js/jquery/tools/overlay/loading.gif" />
</div>
<!-- /overlay element -->