KDE plugin to prevent dithering

PrincessDoreena

Is anyone interested in a kwin effect (KDE desktop effect) which compresses everything to 16 bit color? I made one a while ago to prevent dithering on my laptop with 6bpc panel. In case there is any interest I can update it and publish it.

Update:

Link: https://github.com/PrincessDoreena/kwin-effect-limitcolors

Abeabe

PrincessDoreena Hi, yes I'd like to test it, please upload it, thank you 🙂

PrincessDoreena

Abeabe

karut

dzwdev

https://github.com/PrincessDoreena/kwin-effect-limitcolors

Installation instructions in the README.

Try all the format and offset settings.

karut

I use KDE and would love to try it!

Sunspark

It sounds interesting.. how does it work though? If you're receiving an 8+ bit signal, what do you do from there?

PrincessDoreena

Sunspark

I just discard the last two or three bits.

dzwdev

i'm using manjaro with KDE. how to know if i have temporel dithering? i hope that you post some documentation about "compressing colors to 16 bit".

i'm interested in the script.

dzwdev

PrincessDoreena that what i get:
-B build -S . \

> -DCMAKE_BUILD_TYPE=Release \

> -DCMAKE_INSTALL_PREFIX=/usr

CMake Error: The source directory "/home/pc" does not appear to contain CMakeLists.txt.

Specify --help for usage, or press the help button on the CMake GUI.

cmake --build build --parallel

Error: /home/pc/build is not a directory

Sunspark

PrincessDoreena Hmm.. I don't know that you need to discard.. if you instead re-map to relative colourmetric, all colours that are within the display's gamut in a 16-bit form would stay as they are untouched, and the ones that are outside of it, using relative you could have them instead snap to the nearest matching in-gamut 16-bit colour.

PrincessDoreena

I test with this gif: Loading Image

PrincessDoreena

Sunspark

Wouldn't we need to know the gamut?

PrincessDoreena

dzwdev

Full instructions:

wget https://github.com/PrincessDoreena/kwin-effect-limitcolors/archive/refs/heads/master.zip
unzip master.zip
cd kwin-effect-limitcolors-master
cmake -B build -S . \ -DCMAKE_BUILD_TYPE=Release \ -DCMAKE_INSTALL_PREFIX=/usr cmake --build build --parallel sudo cmake --install build

dzwdev

PrincessDoreena thank you. it is installed now

when i open KwinScripts i don't find the limit color plugin there?

how to know that the script is really installed? and i did not understand how to use that gif to test if dithering is disabled or not?

PrincessDoreena

dzwdev

Workspace Behavior -> Desktop Effects

dzwdev

PrincessDoreena

all the screen dither some times after enabling the plugin

https://ibb.co/VJFVHLp

ryans

dzwdev That's an interesting picture, is it VideoDiff and a capture card?

when i changed from x11 to wayland the problem is not occuring

And you are saying with Wayland + this plugin, dithering goes away, but with X11, the dithering remains? Curious your distro and graphics.

dzwdev

when i changed from x11 to wayland the problem is not occuring

ryans

Thanks @PrincessDoreena for making and open-sourcing this! Does the plugin help your symptoms? Applying these changes at the compositor level is an interesting solution. Does the plugin greatly reduce image quality?

@Sunspark The re-map is another interesting idea. This post from @ravipra appears to do similar.

dzwdev

that is not videodiif. it is just the normal manjaro system.

"you are saying with Wayland + this plugin, dithering goes away, but with X11, the dithering remains?"
with the X11 i get sometimes all the screen dithering like the image i've attached.

this is what i'm using:
Operating System: Manjaro Linux

KDE Plasma Version: 5.27.10

KDE Frameworks Version: 5.113.0

Qt Version: 5.15.11

Kernel Version: 6.6.8-2-MANJARO (64-bit)

Graphics Platform: Wayland

Processors: 4 × Intel® Core™ i5-6300U CPU @ 2.40GHz Memory: 7,6 GiB of RAM

Graphics Processor: Mesa Intel® HD Graphics 520 Manufacturer: Dell Inc.

Product Name: Latitude 7480

ryans

dzwdev Interesting, so that is an actual screenshot? With the plugin enabled, you see that white colored "noise"? Temporal dithering would not be visible in a static screenshot

dzwdev

by the way, how to know the supported bit per pixel (bpp) in my laptop monitor from linux? and how to know the model of the monitor from linux?

laptopmedia shows this: https://laptopmedia.com/screen/lg-lgd0557-lp140wf7/ but the is no bpp information?

Sunspark

dzwdev try typing xrandr --prop and xrandr --verbose in the terminal.