(function(){

    $.fn.centerAxis = function(settings){
        
        var images = $(this);
        
        settings = jQuery.extend({
            itemPerRow:4,
            maxHeight:150
        }, settings);
        
        
        images.each(function(){
        
            var _height = $(this).outerHeight();
            var _margin = (_height >= settings["maxHeight"])? 0: (settings["maxHeight"]-_height)/2;
          
            $(this).css("margin-top",_margin);

        });
        
     };
})(jQuery);