title: Video playback GPUImage and swift
body: <p>I want to process a video with the chromakey filter and the output should be reproduced on the screen.</p>
  
  <p>Below the code I developed that is not showing any video and I can't understand why:</p>
  
  <pre><code>override func viewDidLoad() {
      super.viewDidLoad()
      // Do any additional setup after loading the view, typically from a nib.
      let aSelector : Selector = "start:"
      let tapGesture = UITapGestureRecognizer(target: self, action: aSelector)
      tapGesture.numberOfTapsRequired = 1
      view.addGestureRecognizer(tapGesture)
  }
  
  override func didReceiveMemoryWarning() {
      super.didReceiveMemoryWarning()
      // Dispose of any resources that can be recreated.
  }
  
  @IBAction func start(sender: AnyObject) {
      NSLog("tap pressed")
      play()
  }
  
  func play(){
      let path = NSBundle.mainBundle().pathForResource("glass_buster", ofType: "mp4")
      let player = AVPlayer()
      let pathURL = NSURL.fileURLWithPath(path!)
      NSLog(pathURL.absoluteString)
      let playerItem = AVPlayerItem(URL: pathURL)
      player.replaceCurrentItemWithPlayerItem(playerItem)
  
  
      let gpuMovie = GPUImageMovie(playerItem: playerItem)
      gpuMovie.playAtActualSpeed = true
      let filter = GPUImageChromaKeyFilter()
      gpuMovie.addTarget(filter)
      gpuMovie.playAtActualSpeed = true
  
  
      gpuMovie.startProcessing()
      player.play()
  
  
  }
  </code></pre>