I am looking to control the brightness of a HDMI display from my application.
To control the brightness I try to use the ‘xrandr’ command. Using ‘xrandr’ on a PC (with the same display) I am able to set the screen brightness, but when I try from the Apalis the command has no affect. The following command runs without outputting any errors, but has no affect:
xrandr --output 'DISP3 BG' --brightness 0.5
‘xrandr’ detects the screen no problem:-
root@apalis-imx6:~# xrandr -q Screen 0: minimum 240 x 240, current 1280 x 720, maximum 8192 x 8192 DISP3 BG connected primary 1280x720+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
Can anyone see what I am doing wrong?
Should ‘xrandr’ brightness setting work on the Apalis?
Or is there an alternative method for controlling the screen brightness?
Thanks for your time.