Angular + response headers - can´t access response headers from $http provider

Question

I've tried to access response headers through $http provider without success. In my research I read that it's a CORS issue. But that doesn't make any sense because reading the headers in GoogleChrome inspector(Network section), the headers are there. Code:

$http({
   method: 'POST',
   "url" : url,
   "headers":{
      "Content-Type":"application/json",
      "Ocp-Apim-Subscription-Key":"<SECRETKEY>"
    },
    "data": {"video":fileData}
}).then(
  function successCallback(res){
    console.log("SUCCESS!");
    console.log("RESPONSE JSON ON SERVICE: " + JSON.stringify( res ) );
    console.log("HTTP HEADERS" + JSON.stringify($http.headers) );
    sucxCallback(res.headers);//this came undefined... 
  }
  ,function errorCallback(res){
    console.log("FAIL!")
  }
 );

There is something I can do? I'm considering to change $http to $ajax. Alternatives?

Thx!