Better display color filter

[Density6118]

Android offers an accessibility function to display color filters over the display for various purposes like retaining night vision, or for eye comfort. While the idea is good, the implementation is lacking as these filters make the screen contents look worse, and harder to read.

A legacy root app solved this by basically converting the screen colors to grayscale and then using these luminosity values to apply the desired color. This results in a much better quality result, with better readability. Unfortunately this isn't being supported anymore, and requires root permissions which are a security risk.

It would be amazing if the Samsung team could offer a similar implementation in the future.

Some of the app's source code is available on GitHub:    
https://github.com/Chainfire/inject-hook-cflumen

[realaud]

You can adjust the transparency of the color filters.

[Density6118]

Thanks. It's difficult to describe the difference in quality of these methods. The best demonstration would be to take an old rooted phone and install the cf.lumen app to see for yourself.

Here is a comparison between a basic color filter and cf.lumen's method.    
https://imgur.com/a/DkUmFSy

Hopefully it's visible how in the first example everything looks a bit blurry, like there is a haze over everything, whereas in the second everything is crystal clear but just differently colored.

[realaud]

Adjusting the opacity of the color filter does the same thing.

[Density6118]

I tried varying the intensity, but the quality doesn't compare. It's just a fundamentally different approach to screen coloring. Thanks.