Clight is software that turns your webcam into a light sensor. The software adjusts the screen backlight based on the ambient brightness in your surrounding from captured webcam frames.
The software also manages the screen temperature, and dims the screen after a timeout. Its dimmer module functions without a webcam.
The software is released under an open source license. It’s written in the C programming language.
Key Features
- Very lightweight.
- Support for external monitors.
- Fully valgrind and cppcheck clean.
- External signals catching (sigint/sigterm).
- systemd user unit shipped.
- Quick single capture mode (i.e. do captures, change screen brightness and leave) is provided through a desktop file.
- GAMMA support – computes sunset and sunrise and will automatically change screen temperature.
- DIMMER support – dims your screen after specified timeout of user inactivity (i.e.. no mouse/keyboard activity).
- DPMS support – set desired dpms timeouts for AC/battery states.
- Both DPMS and DIMMER can be disabled while on AC.
- geoclue2 support: when launched without [–lat|–lon] parameters, if geoclue2 is available, it will use it to get user location updates. Otherwise gamma support will be disabled. Location received will be then cached when clight exits. This way, if no internet connection is present (geoclue2 cannot then provide the location) at restart, clight will load the latest available location from a cache file. If no cached location is present, gamma is disabled.
- –sunrise/–sunset times user-specified support: gamma nightly temperature will be set at sunset time, daily temperature at sunrise time.
- Log file, placed in $HOME/.clight.log.
- More frequent captures inside “events”: an event starts by default 30 minutes before sunrise/sunset and ends 30mins after. This is configurable.
- conf file placed in both /etc/default and $XDG_CONFIG_HOME (fallbacks to $HOME/.config/) support.
- Lots of configurations available.
- Only 1 clight instance runs for each user.
- Sweet inter-modules dependencies management system with “modules”(BRIGHTNESS, GAMMA, LOCATION, etc.) lazy loading: every module will only be started at the right time, e.g. GAMMA module will only be started after a location has been retrieved. And modules are gracefully auto-disabled where unsupported (e.g. GAMMA on non-X environments).
- UPower support, to set longer timeouts between captures while on battery, in order to conserve energy.
- Specify curve points to be used to match ambient brightness to screen backlight from config file.
- Clight supports org.freedesktop.PowerManagement.Inhibit interface. This offers the ability, for example, to ensure dimmer doesn’t dim your screen when watching a video.
- Supports both internal laptop monitor and external monitors, courtesy of ddcutil.
- Auto-disable brightness module on PCs without a webcam.
- Check clightd version on clight startup.
- Smooth gamma/dimmer/backlight transitions.
- clight bus interface (org.clight.clight) to make it easy to create a GUI/applet.
Website: github.com/FedeDP/Clight
Support: Wiki
Developer: Federico Di Pierro
License: GNU General Public License v3.0
Clight is written in C. Learn C with our recommended free books and free tutorials.
Related Software
| Eye Care Software | |
|---|---|
| Safe Eyes | Simple and extensible break reminder |
| Clight | Lightweight C daemon that turns your webcam into a light sensor |
| Stretchly | Reminder to take breaks |
| Redshift | Adjusts the color temperature of your display |
| BreakTimer | Set up customizable breaks and will remind you to take them |
| Workrave | Assists in the recovery and prevention of Repetitive Strain Injury |
| ZenBreak | Menu bar app that reminds you to take breaks |
| RSIBreak | Take care of your health and take regular breaks |
| Stretch Break | Digital wellbeing tool that helps you take regular breaks |
| Sane Break | Gentle break reminder |
| Desktop Dimmer | Darker-than-dark dimming for internal and external screens |
Read our verdict in the software roundup.
| Webcam Tools | |
|---|---|
| Webcamoid | Full featured and multi-platform webcam suite with a simple interface |
| ZoneMinder | All-in-one security camera solution |
| Motion | V4L capture program supporting motion detection |
| DroidCam | Turn a mobile device into a network-attached IP camera |
| Kerberos.io | Video surveillance solution |
| Clight | Webcam becomes light sensor |
| webcamize | Use your camera as a webcam |
| Guvcview | Full-featured video grabber |
| Cheese | Take pictures and videos from your webcam |
| Kamoso | Qt-based webcam utility |
| Ekiga | VoIP and video conferencing application |
| camera-streamer | Low-latency camera streaming project for Raspberry Pi systems |
| WebCamControl | GUI app for controlling properties of a webcam |
| Photobooth | Photobooth software for the Raspberry Pi and PC |
| HasciiCam | Live ascii video on the web for the masses |
| camorama | View, alter and save images from a webcam |
Read our verdict in the software roundup.
 Explore our comprehensive directory of recommended free and open source software. Our carefully curated collection spans every major software category.This directory is part of our ongoing series of informative articles for Linux enthusiasts. It features hundreds of detailed reviews, along with open source alternatives to proprietary solutions from major corporations such as Google, Microsoft, Apple, Adobe, IBM, Cisco, Oracle, and Autodesk. You’ll also find interesting projects to try, hardware coverage, free programming books and tutorials, and much more. Discovered a useful open source Linux program that we haven’t covered yet? Let us know by completing this form. |