jQuery mouseover 滑鼠移動切換圖片

(function($){ 
 $.fn.ImgChange = function(settings, imgOut, imgOver, id) {
  var _defaultSettings = {
   bind: "mouseover",
   callback: function () { 
    $("#"+id).attr("src", imgOver);
   }
  };  
  $(this).callSettings(_defaultSettings,settings).mouseout
  (function(){
    $("#"+id).attr("src", imgOut);
  });
 };   
 $.fn.callSettings = function(_defaultSettings,settings) {  
  var _settings = $.extend(_defaultSettings, settings);
  return this.each(function() {
   $(this).bind(_settings.bind, _settings.callback);
  });
 };

})(jQuery);

<Img alt="首頁" id="Img" src="images/off.gif">

/*呼叫*/
$("#ctrl").ImgChange("", "images/off.gif", "images/on.gif", "Img");