Monitor Controller Cross-Platform

A Qt-based desktop application for controlling external monitor settings such as brightness, contrast, and input source selection through DDC/CI (Display Data Channel Command Interface).

Features

• Brightness Control: Adjust monitor brightness using sliders or spin boxes with real-time updates
• Contrast Control: Modify monitor contrast settings with intuitive controls
• Input Source Selection: Switch between different input sources (VGA, DVI, HDMI, DisplayPort, USB-C)
• Multi-Monitor Support: Detect and control multiple connected monitors
• Real-time Feedback: Live updates of current monitor settings
• Cross-Platform Design: Built with Qt for potential cross-platform compatibility

Supported Input Sources

• VGA 1 & 2
• DVI 1 & 2
• DisplayPort 1 & 2
• HDMI 1 & 2
• USB-C

Requirements

Windows

• Windows 10/11 (64-bit)
• Qt 6.x framework
• Visual Studio 2022 (for building from source)
• Monitor with DDC/CI support

Linux (Planned)

• Linux distribution with ddcutil support
• Qt 6.x framework
• Monitor with DDC/CI support

Installation

Pre-built Binaries

1. Download the latest release from the releases page
2. Extract the files to your desired location
3. Run monitorControllerCrossPlatform.exe

Building from Source

Prerequisites

• Qt 6.x SDK
• Visual Studio 2022 with C++ development tools
• CMake (optional)

Build Steps

1. Clone the repository:

   git clone https://github.com/roozbeh-gholami/Monitor-Controller-Cross-Platform.git
   cd Monitor-Controller-Cross-Platform

2. Open the solution file in Visual Studio:

   monitorControllerCrossPlatform.sln
   

3. Build the project:

   • Select your desired configuration (Debug/Release)
   • Build → Build Solution (Ctrl+Shift+B)

4. The executable will be generated in:

   x64/Debug/monitorControllerCrossPlatform.exe
   

   or

   x64/Release/monitorControllerCrossPlatform.exe
   

Usage

1. Launch the Application: Run the executable to open the Monitor Controller interface

2. Monitor Selection: Use the monitor dropdown to select which monitor to control (if multiple monitors are connected)

3. Brightness Control:

   • Use the brightness slider or spin box to adjust monitor brightness
   • Changes are applied when you release the slider or finish editing the spin box

4. Contrast Control:

   • Use the contrast slider or spin box to adjust monitor contrast
   • Changes are applied when you release the slider or finish editing the spin box

5. Input Source: Select the desired input source from the dropdown menu

6. Log Output: Monitor the log box for system messages and error reporting

Technical Details

Architecture

• Framework: Qt 6.x with Widgets module
• Language: C++
• Platform APIs:
  • Windows: DDC/CI via dxva2.lib, lowlevelmonitorconfigurationapi.h, highlevelmonitorconfigurationapi.h
  • Linux: ddcutil command-line interface (planned)

Key Components

• monitorController.h/cpp: Main application logic and monitor control functions
• monitorController.ui: Qt Designer UI layout
• main.cpp: Application entry point
• monitorController.qrc: Qt resource file

DDC/CI Protocol

The application uses the Display Data Channel Command Interface (DDC/CI) protocol to communicate with monitors. This allows software control of monitor settings that are typically only accessible through the monitor's on-screen display (OSD) menu.

Compatibility

Tested Monitors

• Most modern monitors with DDC/CI support
• External monitors connected via HDMI, DisplayPort, DVI, or VGA

Known Limitations

• Some monitors may not support all VCP (Virtual Control Panel) features
• Laptop built-in displays typically don't support DDC/CI
• USB-connected monitors may have limited support

Troubleshooting

Common Issues

1. Monitor not detected:

   • Ensure your monitor supports DDC/CI
   • Try different cable connections
   • Check if DDC/CI is enabled in monitor settings

2. Settings not applying:

   • Verify monitor compatibility
   • Check log output for error messages
   • Try running as administrator

3. Application crashes:

   • Ensure Qt runtime libraries are installed
   • Check Windows compatibility mode if needed

Log Messages

The application provides detailed logging in the log box at the bottom of the interface. Common messages include:

• Monitor detection results
• VCP feature support status
• Error codes and descriptions

Contributing

1. Fork the repository
2. Create a feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add some amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

Future Enhancements

• Linux support with ddcutil integration
• macOS support
• Color temperature control
• Monitor profiles and presets
• System tray integration
• Hotkey support
• Multiple monitor configuration management

License

This project is licensed under the MIT License - see the LICENSE file for details.

Acknowledgments

• Qt Framework for the cross-platform GUI toolkit
• Microsoft DDC/CI APIs for Windows monitor control
• ddcutil project for Linux monitor control inspiration

Author

Roozbeh Gholami

• GitHub: @roozbeh-gholami

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Note: This application requires monitors that support DDC/CI protocol. Not all monitors support this feature, particularly older models or some budget displays.