(function($) {

     $.fn.myZoom = function(options) {

         var defaults = {
             id: 'my_zoom',
             parent: 'body',
             append: true,
             preload: 'Loading...',
             error: 'There has been a problem with loading the image.'
         };

         var obj;
         var img = new Image();
         var loaded = false;
         var found = true;
         var timeout;
         var w1, w2, h1, h2, rw, rh;
         var over = false;

         var options = $.extend(defaults, options);

         this.each(function() {

             obj = this;
             // works only for anchors
             var tagName = this.tagName.toLowerCase();
             if (tagName == 'a') {

                 var href = this.href; 		
                 img.src = href + '?' + (new Date()).getTime() + ' =' + (new Date()).getTime();
                 $(img).error(function() { found = false; })
                 img.onload = function() {
                     loaded = true;
                     img.onload = function() { };
                 };

                 $(this)
					.css('cursor', 'crosshair')
					.click(function(e) { e.preventDefault(); })
					.mouseover(function(e) { start(e); })
					.mouseout(function() { hide(); })
					.mousemove(function(e) { move(e); })
             };

         });

         function start(e) {
             hide();
             var zoom = $('<div id="' + options.id + '">' + options.preload + '</div>');
             if (options.append) { zoom.appendTo(options.parent) } else { zoom.prependTo(options.parent) };
             if (!found) {
                 error();
             } else {
                 if (loaded) {
                     show(e);
                 } else {
                     loop(e);
                 };
             };
         };

         function loop(e) {
             if (loaded) {
                 show(e);
                 clearTimeout(timeout);
             } else {
                 timeout = setTimeout(function() { loop(e) }, 200);
             };
         };

         function show(e) {
             over = true;
             $(img).css({ 'position': 'absolute', 'top': '0', 'left': '0' });
             $('#' + options.id).html('').append(img);
             w1 = $('img', obj).width();
             h1 = $('img', obj).height();
             w2 = $('#' + options.id).width();
             h2 = $('#' + options.id).height();
             w3 = $(img).width();
             h3 = $(img).height();
             w4 = $(img).width() - w2;
             h4 = $(img).height() - h2;
             rw = w4 / w1;
             rh = h4 / h1;
             move(e);
         };

         function hide() {
             over = false;
             $('#' + options.id).remove();
         };

         function error() {
             $('#' + options.id).html(options.error);
         };

         function move(e) {
             if (over) {
                 // target image movement
                 var p = $('img', obj).offset();
                 var pl = e.pageX - p.left;
                 var pt = e.pageY - p.top;
                 var xl = pl * rw;
                 var xt = pt * rh;
                 xl = (xl > w4) ? w4 : xl;
                 xt = (xt > h4) ? h4 : xt;
                 $('#' + options.id + ' img').css({ 'left': xl * (-1), 'top': xt * (-1) });
             };
         };

     };

 })(jQuery);
jQuery.noConflict();