jQuery.fn.center = function(params) {
var options = {
vertical: true,
horizontal: true
}
op = jQuery.extend(options, params);
return this.each(function(){
 var $self = jQuery(this);
 var width = $self.width();
var height = $self.height();
 var paddingTop = parseInt($self.css("padding-top"));
var paddingBottom = parseInt($self.css("padding-bottom"));
 var borderTop = parseInt($self.css("border-top-width"));
var borderBottom = parseInt($self.css("border-bottom-width"));
 var mediaBorder = (borderTop+borderBottom)/2;
var mediaPadding = (paddingTop+paddingBottom)/2;
 var positionType = $self.parent().css("position");
 var halfWidth = (width/2)*(-1);
var halfHeight = ((height/2)*(-1))-mediaPadding-mediaBorder;
 var cssProp = {
position: 'absolute'
};
if(op.vertical) {
cssProp.height = height;
cssProp.top = '50%';
cssProp.marginTop = halfHeight;
}
if(op.horizontal) {
cssProp.width = width;
cssProp.left = '50%';
cssProp.marginLeft = halfWidth;
}
 if(positionType == 'static') {
$self.parent().css("position","relative");
}
 $self.css(cssProp);
});
};