HIGHGUI ERROR: V4L: /dev/video0 unable to query number of devices

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I am on an ODROID-U2 ARM device, and I can't run any openCV code because of this error. my camera is listed in /dev/v4l and it seems to be outputting data in /dev/video0. I've tried opening cam with the argument -1 (which I believe searches for any open camera), but still nothing. Any help would be appreciated, thanks.