Bug 513608

Summary:	Use webcam to detect ambient light level so that ambient-light-based brightness control works on systems without an ambient light sensor
Product:	[Plasma] kwin	Reporter:	Philippe ROUBACH <philippe.roubach>
Component:	general	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	REPORTED ---
Severity:	wishlist	CC:	natalie_clarius, nate
Priority:	NOR
Version First Reported In:	6.5.4
Target Milestone:	---
Platform:	Other
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Philippe ROUBACH 2025-12-20 14:28:00 UTC

I don't find my bug report, so I resend it.

I use with success, with X11, with KDE, Clight.
see https://github.com/FedeDP/Clight

I wish this tech or a similar one were integrated into KDE with Wayland.

Clight uses the webcam as ligth sensor to adjust the brightness, color and backlight of the screen with ambient light.

Thanks

Comment 1 Philippe ROUBACH 2025-12-21 08:44:30 UTC

I forgot: Clight is also able to use a light sensor

Comment 2 Nate Graham 2025-12-22 21:43:01 UTC

Automatic brightness using an embient light sensor was just implemented the other day; see Bug 502122.

I'm not sure how much it makes sense to adjust screen colors based on the ambient brightness, so let's limit this to a request for a webcam to be used as a brightness measurement device on systems without an ambient light sensor. Moving to KWin to see if it's a feasible thing to support.

Comment 3 Philippe ROUBACH 2025-12-22 22:22:13 UTC

Why adjust the color when the night begins? Because the ambient light decreases.
So it makes sense to adjust the color with the ambient light. No need to know the hour of the nightfall.
Adjusting the color at the hour of the beginning of the night is not accurate:
- In case of a cloudy day, the night begins sooner than the astronomical nightfall.
- The shadow cast by a mountain over the valley plunges the valley into darkness well before astronomical nightfall.
- If you are in a room without any light or with low light.