问题
I've downloaded and installed cygwin for windows, I downloaded opencv (ported version for cygwin) and installed it successfully and my code compiles.
The problem I have is that CvCapture* capture = cvCreateCameraCapture(-1); is always null!
The usb webcam is connected and is not in use. Why I can't access my webcam in cygwin? (Is there any particular reason like for example I should mount the device first, If this is the case I have no knowledge about it)
Please advice
来源：https://stackoverflow.com/questions/7706523/cannot-access-usb-webcam-through-opencv-cygwin