title: How to record video in ProRes codec on iOS?
body: <p>I would like to capture video from device’s back camera directly to ProRes codec, now that <code>.proRes422</code> and <code>.proRes4444</code> are available as <code>AVVideoCodecType</code> options in iOS 11.</p>
  
  <p>But I receive an error that recording is:</p>
  
  <blockquote>
    <p>unsupported given the current configuration</p>
  </blockquote>
  
  <p>On both iPhone X and second generation iPad Pro, when trying to capture video with the following code:</p>
  
  <pre><code>movieFileOutput.setOutputSettings([AVVideoCodecKey: AVVideoCodecType.proRes422], 
                                    for: movieFileOutputConnection!)
  </code></pre>
  
  <p>If this approach is wrong, can the captured video be encoded by using <code>AVCaptureVideoDataOutput</code> alongside <code>AVAssetWriter</code>?</p>