text: KityMinder.registerProtocal('json', function() {
      function filter(key, value) {
          if (key == 'layout' || key == 'shicon') {
              return undefined;
          }
          return value;
      }
      return {
          fileDescription: 'KityMinder',
          fileExtension: '.km',
          mineType: 'application/json',
          encode: function(json) {
              return JSON.stringify(json, filter);
          },
          decode: function(local) {
              return JSON.parse(local);
          },
          recognize: function(local) {
              return Utils.isString(local) && local.charAt(0) == '{' && local.charAt(local.length - 1) == '}';
          },
          recognizePriority: 0
      };
  });