title: How to use an url address to open a camera with FrameGrabber?
body: <p>I'm working in a image processing project and I have to use a camera and a projector; The project is programmed with javacv.
  I can access to the camera with a external URL and take snapshots. However, I need to calibrate both, camera-projector so while I was looking for information in the red I found a code called "Procamcalib" that allow me to calibrate both and it also works. The problem is that the calibration program use the function " FrameGrabber" for accessing to the camera and instead of open the external camera, it open the camera of my laptop. 
  The thing is, when is used FrameGrabber (0), the zero value determine the device number but I have to access to the camera with an external URL, and I can't put in the code the direction when is used OpenFrameGrabber.
  I would like to know how can I combine both functions or something similar to fix the program and open the correct camera.
  Thank you!</p>