LyraBrightness

A small portable brightness utility for Windows 11.

LyraBrightness runs from the system tray and tries to control real monitor brightness through DDC/CI when the monitor supports it. If that is not available, it automatically switches to Software dimming, which visually darkens the screen without changing the monitor's physical backlight.

Why this project is structured for trust

This repository/package is meant to be easy to inspect.

What is included:

• main.cpp — full source code of the application
• app.rc — Windows resource file used to embed the icon into the executable
• LyraBrightness.exe — ready-to-run portable build
• SHA256SUMS.txt — checksums so users can verify files were not changed
• KNOWN_ISSUES.md — limitations and expected edge cases
• SECURITY_AND_PRIVACY.md — plain-language explanation of what the app does and does not do
• BUILDING.md — exact build instructions for MinGW on Windows
• CHANGELOG.md — current release notes

Main features

• Portable: one executable, no installer required
• Tray icon with left-click open / right-click menu
• Real hardware brightness control through DDC/CI when available
• Automatic fallback to Software dimming when DDC/CI is unavailable
• Safety floor in Software dimming mode to avoid turning the screen fully black
• Build information dialog
• Single-instance protection
• Explorer tray icon recovery after shell restart

How brightness modes work

1. Hardware brightness

This is the preferred mode.

LyraBrightness sends brightness commands directly to the monitor through DDC/CI. This changes the actual monitor brightness.

Requirements:

• monitor supports DDC/CI
• DDC/CI is enabled in the monitor OSD/menu
• cable / adapter / GPU path allows DDC/CI communication

2. Software dimming

This is a fallback mode.

LyraBrightness places a transparent black overlay over the desktop. This does not change physical monitor brightness. It only makes the image look darker.

This exists for cases such as:

• old monitors
• DVI/VGA/adapter setups
• monitors with no working DDC/CI access from Windows

The application states this clearly in the UI so the user knows exactly which mode is active.

Portable use

If the build is successful, users can normally run:

• LyraBrightness.exe

No installation is required.

Quick user notes

• If the app says Hardware brightness, it is controlling real brightness.
• If the app says Software dimming, it is visual dimming only.
• If your monitor is old or connected through adapters, fallback mode is common and expected.

Verification

Before sharing the executable, compare it against SHA256SUMS.txt. Users can verify the release hash with PowerShell:

Get-FileHash .\LyraBrightness.exe -Algorithm SHA256

Recommended way to share

For trust, do not send just a random .exe in chat. Share:

• the source files
• this documentation
• the checksum file
• the compiled release

That gives users enough information to inspect the project or build it themselves.