Upload a simple image with ng-flow and AngularJS

Question

I'm trying to use ng-flow to use an image in javascript to send it to a backend server using a RPC call. The problem is that I follow the tutorial that they have in his page , but I don't find how can access to image in a JavaScript controller inside AngularJS app.

I'm very novice still in Angular and maybe this problem isn't a big problem but I don't found the way to do this.

The code that I have is very simple, a simple html code:

<div class="container"  flow-init
    flow-file-added="!!{png:1,gif:1,jpg:1,jpeg:1}[$file.getExtension()]"
      flow-files-submitted="$flow.upload()">
  <h1>flow image example</h1>
  <hr class="soften"/>


  <div>
    <div class="thumbnail" ng-hide="$flow.files.length">
      <img src="http://www.placehold.it/200x150/EFEFEF/AAAAAA&text=no+image" />
    </div>
    <div class="thumbnail" ng-show="$flow.files.length">
      <img flow-img="$flow.files[0]" />
      <h2>{{$flow.files[0].name}}</h2>
    </div>
    <div>
      <span class="uk-button" ng-hide="$flow.files.length" flow-btn flow-attrs="{accept:'image/*'}">Select image</span>

      <a href="#" class="btn" ng-show="$flow.files.length" flow-btn flow-attrs="{accept:'image/*'}">Change</a>
      <a href="#" class="btn btn-danger" ng-show="$flow.files.length" ng-click="$flow.cancel()"> Remove </a>

      <span class="uk-button" flow-btn>Upload File</span>

    </div>
    <p>
      Only PNG,GIF,JPG files allowed.
    </p>
  </div>
</div>

And the factory that ng-flow need is:

routerApp.config(['flowFactoryProvider', function (flowFactoryProvider) {


flowFactoryProvider.defaults = {
    target: 'upload.php',
    permanentErrors: [404, 500, 501],
    maxChunkRetries: 1,
    chunkRetryInterval: 5000,
    simultaneousUploads: 4,
    singleFile: true
  };
  flowFactoryProvider.on('catchAll', function (event) {      
    console.log('catchAll', arguments);
  });
  }]);

And I have too the code to the controller to this page. I tried to access to image but I don't know how do this.

Any idea?

If you know any way to do this with other tool or know a good tutorial, I really would like to know.

Thanks fo all.