title: Set round corners AVPlayer video frame
body: <p>Anyone knowns how to set round corner to the video frame using AVPlayer?
  I'm trying doing this:</p>
  
  <pre><code>- (void)loadVideoWithPlayer:(AVPlayer*)playerVideo
  {    
      dispatch_async(dispatch_get_main_queue(), ^{
  
          AVPlayerLayer *avLayer = [AVPlayerLayer playerLayerWithPlayer: playerVideo];
          [avLayer setCornerRadius:20];
          [avLayer setMasksToBounds:YES];
  
          [self.playerViewController setPlayer:playerVideo];
  
          [self insertSubview:self.playerViewController.view belowSubview:self.interactView];
  
          [self.playerViewController.player play];
      });
  }
  </code></pre>
  
  <p>but it's not working. I can't set round corners to the <code>AVPlayer.playerViewController.view</code> because the video frame could be different.</p>