Webcam setup

I use a NexiGo N660p camera, which is pretty much plug and play.

You can find out what it is connected path by using the command ls /dev/v* first before plugging it in and then again after. You should see the camera show up as /dev/video0 if you have no other video capable USB devices plugged in. The N660p showed up as two devices (video0 and video1). In this case we'll just use /dev/video0. Installing the program v4l2 allowed to disable autofocus and tweak camera settings for better performance.

sudo apt install v4l-utils

Help and controls can be found by typing v4l2-ctl --help

To see what features/controls v4l2 can do for your camera use: v4l2-ctl -d /dev/video0 --list-ctrls

You should see something like this.

                     brightness 0x00980900 (int)    : min=-64 max=64 step=1 default=0 value=-10
                       contrast 0x00980901 (int)    : min=0 max=100 step=1 default=34 value=34
                     saturation 0x00980902 (int)    : min=0 max=128 step=1 default=50 value=70
                            hue 0x00980903 (int)    : min=-180 max=180 step=1 default=0 value=0
 white_balance_temperature_auto 0x0098090c (bool)   : default=1 value=1
                          gamma 0x00980910 (int)    : min=100 max=500 step=1 default=300 value=300
                           gain 0x00980913 (int)    : min=0 max=128 step=1 default=64 value=64
           power_line_frequency 0x00980918 (menu)   : min=0 max=2 default=1 value=1
      white_balance_temperature 0x0098091a (int)    : min=2800 max=6500 step=10 default=4600 value=4600 flags=inactive
                      sharpness 0x0098091b (int)    : min=0 max=100 step=1 default=40 value=40
         backlight_compensation 0x0098091c (int)    : min=0 max=2 step=1 default=0 value=2
                  exposure_auto 0x009a0901 (menu)   : min=0 max=3 default=3 value=1
              exposure_absolute 0x009a0902 (int)    : min=50 max=10000 step=1 default=166 value=150
         exposure_auto_priority 0x009a0903 (bool)   : default=0 value=1
                   pan_absolute 0x009a0908 (int)    : min=-57600 max=57600 step=3600 default=0 value=0
                  tilt_absolute 0x009a0909 (int)    : min=-43200 max=43200 step=3600 default=0 value=0

                 focus_absolute 0x009a090a (int)    : min=0 max=1023 step=1 default=0 value=270
                     focus_auto 0x009a090c (bool)   : default=1 value=0
                  zoom_absolute 0x009a090d (int)    : min=0 max=3 step=1 default=0 value=0

To disable auto-focus, you can use the --set-ctrl flag

v4l2-ctl -d /dev/video0 --set-ctrl=focus_auto=0

I created a fixcam.sh bash file that I input all of the tweaks. Make sure the file is executable.

chmod +x /path/to/fixcam.sh

To make sure the script runs after every reboot, use crontab -e, and append following line to the file then save and exit

@reboot bash /home/octoprint/fixcam.sh