Automatically reduce brightness

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Revision as of 20:15, 10 April 2007 by OumU7h (Talk | contribs)
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The idea

When watching someone working with an iBook I noticed that the brightness automatically faded to the lowest level after a few seconds of inactivity. I think that this is a simple way to save power. I wrote a c-daemon which uses the XScreenSaver extension to check whether the user is active. If he is not, it lowers the brightness to a specific level. When he is active again, the brightness is reset to the previous level.


A recent kernel with IBM ACPI extensions. (You should have a file called /proc/acpi/ibm/brightness)


  1. Download the brightness control daemon
  2. Unpack it and chdir into the brightd directory
  3. Call $ make
  4. Move the brightd executable into a directory like /usr/local/bin
  5. Put $ brightd -d into your ~/.Xsession (or another distro-specific startup script)
  6. Change the permissions of /proc/acpi/ibm/brightness so that your user can write to that file

See the README for more detailled instructions and command line parameters.

Example installation for Gentoo linux and XFCE4

$ wget -o /dev/null -O brightd.tar.bz2 "