.filter('unique', function() {
   return function(collection, keyname) {
      var output = [],array_values=[] ;
      angular.forEach(collection, function(item) {
          var key = item[keyname];
          output[key] = item ;
      });
     
     for (var key in output) {
       array_values.push(output[key]);
     }
      return array_values;
   };
})