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Windows 7, 8.1, 10 (64-bit)

↳ v0.9.64 Changelog


8.1/10 recommended. (See why below)


If the sliders don't work beyond a certain value, start the app in admin mode once, then restart the system. This disables a limit that Windows imposes on how much an app can change screen values.

Linux (X11 only)

Get these packages (for Ubuntu-based distros):
sudo apt install build-essential libgl1-mesa-dev libxext-dev libxxf86vm-dev qt5-default
Install and run:

Alternatively, the app is currently packaged in the AUR and Gentoo GURU Overlay.


What is it?

It's a free and open source tool whose purpose is to aid the eyes in adapting to rapid changes in screen brightness.

It can dim the screen if its content is too bright, or brighten it otherwise. This can help your eyes adjust when switching between dark and light windows, especially at night or in suboptimal lighting conditions.

How to use it?

Instructions are here.

How does it work?

Gammy periodically captures the screen, then gradually adjusts the brightness based on its contents. The screen capture process is hardware accelerated and highly performant.

Why is Windows 8.1/10 recommended over Windows 7?

The interface used for fast screen captures is not available in Windows 7. A less efficient method is used instead, which might cause screen stutters.