title: OpenCV + OS X + external webcam = very slow
body: <p>I'm using openCV on OS X with my external webcam (Microsoft Cinema HD Lifecam) and its performance is very low even with the simplest camera readout code.</p>
  
  <pre><code>import cv2
  cap = cv2.VideoCapture(1)
  
  while(cap.isOpened()):
      ret, frame = cap.read()
      cv2.imshow("Output", frame)
      if cv2.waitKey(1) &amp; 0xFF == ord('q'):
          break
  
  cap.release()
  cv2.destroyAllWindows()
  </code></pre>
  
  <p>I tried the same webcam with Photo Booth and it works well with high FPS. Also, I tried the same code with the built-in Facetime camera of my mac and it worked pretty fast. So, it seems like that I have some kind of configuration issue in OpenCV.</p>
  
  <p>Has somebody ever experienced something like this? 
  Thanks for your answers.</p>