title: How to use a camera with OpenCV
body: <p>I'm trying to learn OpenCV. I have been playing around with it for an entire day trying to get it to recognize my camera. I just can't get it to work and I can't find any information about it.</p>
  
  <p>My camera is a usb xbox live webcam, as soon as I connected it to my computer windows recognized it as if it were its own child and installed the drivers.</p>
  
  <p><em>DISCLAIMER</em> I'm like completely clueless as I have never worked with cameras before in code and I don't know how hard or difficult it would be to use one, nor do I know where to start, what information to look up, or anything like that. :( <em>DISCLAIMER</em></p>
  
  <p>I found this example on the opencv website at this url:
  <a href="http://opencv.willowgarage.com/wiki/CameraCapture" rel="noreferrer">http://opencv.willowgarage.com/wiki/CameraCapture</a></p>
  
  <p>I copy and pasted the first one which says "Here is a simple framework to connect to a camera and show the images in a Window.". I formatted it correctly and got it to compile and run perfectly, but it gives the error "ERROR: capture is NULL" when I execute it(not a compiler error, its an error in the application)</p>