title: Capture screen and audio with objective-c
body: <p>I'm using an AVCaptureSession to create a screen recording (OSX), but i'd also like to add the computer audio to it (not the microphone, but anything that's playing through the speakers) i'm not really sure how to do that so the first thing i tried was adding an audio device like so:</p>
  
  <pre><code>AVCaptureDevice *audioDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeAudio];
  </code></pre>
  
  <p>After adding this device the audio was recorded, but it sounded like it was captured through the microphone. Is it possible to actually capture the computer's output sound this way? like quicktime does.</p>