BlockInput

BlockInput is a utility tool designed for presenters, teachers, and public speakers. It allows you to lock your computer's input devices (keyboard and mouse) to prevent unauthorized access while keeping the screen active for movies, slideshows, or demonstrations.

It features an "Exception List" that allows specific keys (like the Spacebar) to function even when the computer is locked, enabling you to control your presentation without unlocking the entire system. Additionally, it provides security features like webcam capture and event logging if someone attempts to use the computer without the password.

🚀 Features

• Selective Input Blocking: Blocks keyboard and mouse inputs while allowing the screen to remain visible and active.
• Exception List: Define specific keys to allow through the block (e.g., Spacebar for pausing video or advancing slides).
• Security Camera: Automatically captures a photo via webcam if unauthorized keys or mouse movements are detected.
• Activity Logging: Logs keystrokes and events during the blocked session.
• Password Protection: Unlocking requires typing a predefined password (blind typing).
• System Hardening: Disables system shortcuts like Alt+Tab and Ctrl+Alt+Del (via Registry policy) during the lock session to prevent bypassing.
• Tray Icon Support: Runs quietly in the system tray.

🛠️ Built With

• Language: Delphi (Pascal)
• Framework: VCL (Visual Component Library)
• Dependencies:
  • DirectShow9 (via VSample.pas and VFrames.pas included in LIB/) for Webcam support.
  • Windows Hooks (User32.dll) for input interception.

📦 Installation

1. Clone the repository:

   git clone [https://github.com/yourusername/blockinput.git](https://github.com/yourusername/blockinput.git)

2. Open the Project: Open BlockInput.dproj in Embarcadero Delphi.
3. Build: Compile the project (Win32 or Win64) to generate the executable.

📖 How to Use

1. Launch the Application: Run BlockInput.exe.
2. Configuration:
   • WebCam: Select your webcam device from the dropdown if you want to enable photo capture on intrusion attempts.
   • Save Path: Choose where logs and photos should be saved.
   • Exceptions: Press keys in the "Exception List" text box to add them to the allowlist (e.g., press Spacebar). Select "Allow" to let these keys pass through the block.
   • Password: Set your unlock password (default is BLOCKINPUT).
3. Activate Block:
   • Right-click the Tray Icon and select "Block in 5 seconds".
   • The tool will disable Task Manager and other system keys, then lock input.
4. Unlocking:
   • Type your password directly (nothing will appear on screen) to unlock the computer.
   • If you type the password correctly, the input is restored and the webcam stops recording.

⚠️ Important Note

This tool modifies Windows Registry keys (DisableTaskMgr, DisableLockWorkstation, etc.) temporarily to ensure the computer stays locked. If the program crashes or is forced closed unexpectedly, these restrictions might remain. Restarting the application and closing it properly usually reverts these changes.

📄 License

This project is licensed under the Apache License 2.0 - see the LICENSE file for details.

👤 Author

Franco M A Caixeta