I'm running Ubuntu 12.04 on this machine. I'm trying to do some programming using the OpenCV and OpenCL libraries and got a webcam to play with some of their features.

When I log in physically to the box (sitting there), I can access the webcam from OpenCV, but more importantly, from gstreamer-properties (the test video shows the webcam output just fine).

However, when I log in via NX (Nomachine NX client), while everything else /seems/ the same, I can't access the webcam.

I do still see
/dev/v4l/by-id/usb-Microsoft_Microsoft??_LifeCam_VX-2000-video-index0 -> ../../video0

I just can't access it. gstreamer-properties doesn't see any devices, and OpenCV doesn't find anything either (gets a null response when trying to activate video0).

I'm not sure what to check and don't know why a remote login via nx is different than a physical login (though obviously it is in some way).