Filter json objects with Angular js ng-repeat directive

In my angular js controller, I have a json array that contains continents and inside the continents contain an array of countries

 //CONTROLLER
app.controller('CountryController', function(){

    this.continents = 
    [
         {
                name:'Africa',
                countries:
                [
                    { name: 'Algeria', code:'DZ', operators:'3'},
                    { name: 'Angola', code:'AO', operators:'1'},
                    { name: 'Benin', code:'BJ', operators:'2'},
                    { name: 'Burkina Faso', code:'BF', operators:'1'}
                ],
          },


         {
               name:'AsiaPacific',
                countries:
                [
                    { name: 'Afghanistan', code:'AF', operators:'4'},
                    { name: 'Bahrain', code:'BH', operators:'2'}
                ],
          }
    ];

});

In my view i want to display the countries in tabbed elements arranged by continents i.e I have tabs to hold the countries in each continent. e.g i have a tab for Africa and inside this tab i want to display the countries in the Africa object. I have tried using the 'filter' to display only countries in a particular continent in each tab but it is not working neither does anything show up. On inspecting the element the code seems to be commented. This is the first task I am trying to accomplish using Angular-js so I am still learning the ropes.

This is what my view looks like

       <div ng-app="countriessupported" class="container container_with_height">
                    <div ng-controller="CountryController as countryCtrl" id="myTabContent"  class="tab-content hidden-xs">
                             <div class="tab-pane fade active in" id="africa">
                                   <div class="col-md-12 countries_col-12" ng-repeat="continent in countryCtrl.continents.name | filter: 'Africa' ">

                                             <a href="">
                                                <div class="col-md-3 country_container" ng-repeat="country in continent.countries">

                                                  <div class="country_name">
                                                      {{ country.name }}
                                                   </div>
                                                </div>
                                           </a>

                                   </div>
                           </div>
                        </div>
            </div>

So the idea is to have the countries repeated in the div with class col-md-3 How can i achieve this please?