Webcam not working Ubuntu 18.04

I have installed Ubuntu 18.04, but the applications (Skype, Cheese) says no device found.

I have reviewed several topics on the subject, but none seem to work. Thank you!

Edit: In a beginning the output of ls -l /dev/video0 is:

ls: Cannot access an '/dev/video0': file or directory does not exist.

Then when I put

sudo mknod /dev/video0 c 81 0 

We have the output for ls -l /dev/video0 is:

crw-r--r-- 1 root root 81, 1 Apr 19 22:25 /dev/video0

Output getfacl /dev/video and ls -ltrh /dev/video*

Output lsusb and v4l2-ctl --list-devices

Output 'Cheese' by terminal. And when the camera is activated, it says: 'No device found'

1 Answer

The group and permissions for your /dev/video0 are not correct. The groop root for your /dev/video0 will deny access to the camera for users outside this group.

The output of ls -l /dev/video0 should look like this:

crw-rw----+ 1 root video 81, 1 Apr 19 22:25 /dev/video0

Try fixing the group by running:

sudo chown root:video /dev/video0

Then fix permissions by running:

sudo chmod 660 /dev/video0