Archives For screen brightness

screen brightness

Running Ubuntu on a laptop? You may found that Ubuntu doesn’t memorize your screen brightness level. Every time you reboot or wake the machine up from sleep, it resets the screen brightness to maximum level.

I’ve written how to save screen brightness level in Ubuntu, but it might not work for all video adapters.

Thanks to Norbert, he made a sysvinit-backlight script that automatically remembers your screen brightness level for all video adapters and loads the backlight levels on boot, reboot, or wake up from sleep.

To install the script:

Open terminal (Ctrl+Alt+T) and run below commands one by one to get it from Norbert’s PPA:

sudo add-apt-repository ppa:nrbrtx/sysvinit-backlight

sudo apt-get update

sudo apt-get install sysvinit-backlight

If you don’t want to add PPA, you may grab the script directly from PPA packages page. So far, Ubuntu 14.10, Ubuntu 14.04 and Ubuntu 12.04 are supported.

For more you may contact the the script author at launchpad.net.

save ubuntu backlight settings

Laptop users still have the backlight issue in Ubuntu 14.04. Every time Ubuntu boots up you get the maximum level of screen brightness.

Here’s a workaround by adding a startup script which will automatically adjust screen brightness when Ubuntu boots up.

To get started:

Preparation: Open your file browser and navigate to “Computer-> sys -> class -> backlight” directory. You’ll see two or three folders there:

Find Out Actual Backlight Settings Folder

Find Out Actual Backlight Settings Folder

In each folder there’s a file called actual_brightness, you can see its content (brightness value) through the thumbnail icon.
actual-brightness

Remember them and do:

  • Change your screen brightness through Fn + Arrow key.
  • Check out the actual_brightness files in each folder (Re-open each folder to refresh the value).
  • Does the value change?
  • Remember the folder name in which the value of actual_brightness changes.
  • Replace acpi_video0 in below commands with that folder name

1. Press Ctrl+Alt+T on keyboard to open the terminal. When it opens, run the command below will give you the maximum level of your laptop backlight:

cat /sys/class/backlight/acpi_video0/max_brightness

Mine is 9, so I can set backlight level from 0 to 9.

2. Run the command below one by one. You’ll get the super user privilege and open the /etc/rc.local file, a script executed at the end of each multiuser runlevel, with gedit editor.

sudo -i

gedit /etc/rc.local

Add the line below before the last. Change the number 0 to the brightness level you want.

echo 0 > /sys/class/backlight/acpi_video0/brightness

save screen brightness ubuntu 14.04

That’s it. Enjoy!

save ubuntu backlight settings

As your may know, every time Ubuntu boots up you get the maximum level of screen brightness on laptop. Here’s a way to save your brightness by adding a startup script which will automatically adjust screen brightness when Ubuntu boots up.

Tutorial Objectives:

  • Save your screen brightness in Ubuntu 13.10
  • Enjoy!

To get started, press Ctrl+Alt+T on your keyboard to open terminal. When it opens, run commands below:

cat /sys/class/backlight/acpi_video0/max_brightness

It outputs the maximum level of your laptop backlight. Mine is 9. The minimum is 0.

Run command below to edit the /etc/rc.local file, which is a script executed at the end of each multiuser runlevel.

sudo gedit /etc/rc.local

Add following before the last line. Change 0 to the brightness level as you want (from 0 to the max)

echo 0 > /sys/class/backlight/acpi_video0/brightness

save-screen-brightness