title: cv2.VideoCapture.open() always returns FALSE
body: <p>I am trying to access a Logitech c310 webcam on my beaglebone. It always returns false for any device ID, I am not sure why.</p>
  
  <p>I use the following code.</p>
  
  <pre><code>&gt;&gt;&gt; import cv2, numpy as np
  &gt;&gt;&gt; cam = cv2.VideoCapture(0)
  &gt;&gt;&gt; cam.open(0)
  False
  </code></pre>
  
  <p>The camera does show up as video0 in dev/ and also in <code>root@arm:~#lsusb</code>, like below,</p>
  
  <pre><code>root@arm:~# lsusb
  Bus 001 Device 002: ID 046d:081b Logitech, Inc. Webcam C310
  Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
  Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
  </code></pre>
  
  <p>I could also access  the camera with <code>v4l2-ctl</code>. 
  Note that I am very new to OpenCV, so this may sound silly and I apologize for that in advance.</p>