I tried to run the following:
$ vlc -I dummy v4l2:///dev/video0 --video-filter scene --no-audio --scene-path webcam.png --scene-prefix image_prefix --scene-format png vlc://quit --run-time=1
VLC media player 2.0.7 Twoflower (revision 2.0.6-54-g7dd7e4d)
[0x1f4a1c8] dummy interface: using the dummy interface module...
[0x7fc19c001238] v4l2 demux error: VIDIOC_STREAMON failed
libv4l2: error setting pixformat: Device or resource busy
libv4l2: error setting pixformat: Device or resource busy
libv4l2: error setting pixformat: Device or resource busy
libv4l2: error setting pixformat: Device or resource busy
libv4l2: error setting pixformat: Device or resource busy
libv4l2: error setting pixformat: Device or resource busy
libv4l2: error setting pixformat: Device or resource busy
libv4l2: error setting pixformat: Device or resource busy
libv4l2: error setting pixformat: Device or resource busy
libv4l2: error setting pixformat: Device or resource busy
[0x7fc19c007f18] v4l2 access error: cannot set input 0: Device or resource busy
[0x7fc19c007f18] v4l2 access error: cannot set input 0: Device or resource busy
[0x7fc1a4000b28] main input error: open of `v4l2:///dev/video0' failed
[0x7fc1a4000b28] main input error: Your input can't be opened
[0x7fc1a4000b28] main input error: VLC is unable to open the MRL 'v4l2:///dev/video0'. Check the log for details.
[0x7fc19c007cc8] idummy demux: command `quit'
So I'm assuming that there is a program currently accessing my webcam, which is cumbersome since its light is off and lsof | grep /dev/video returns nothing. Is there another, proper way to check what processes are currently using my webcam? Or is the problem of an entirely different nature?
Best Answer
I was having the same problem and the solution at http://www.theoutpost.org/8-nslu2/open-devvideo0-device-or-resource-busy/ (EDIT: url updated) helped me.