[Plugin: WooCommerce Dynamic Gallery] adding a around image

Hey. I am wanting to implement some custom code in to this plugin. In order to do this i need to locate where this bit of code is generated. I have looked everywhere but it isn’t clear:

<div class="ad-image" style="width: Xpx; height: Xpx; top: 0px; left: 0px;"><img src="http://www.x.com/X.jpg" rel="x" class="lightbox" alt="" idx="0" style="width: Xpx; height: Xpx;"></div>

All i need to do it add a span around the img tag so it looks like this:

<div class="ad-image" style="width: Xpx; height: Xpx; top: 0px; left: 0px;"><span><img src="http://www.x.com/X.jpg" rel="x" class="lightbox" alt="" idx="0" style="width: Xpx; height: Xpx;"></span></div>

Can you give me any clue how i might do this.

Thank you