Features

⭐ Automatically toggle on/off your Logitech Litra USB device when your webcam is in use. Works for any app, like Teams, Zoom, OBS, etc.

⭐ Control the Litra color temperature, brightness, and manual on/off via the systray icon. You can also disable the automatic camera detection feature if you'd like.

Requirements

• Windows PC (tested on Windows 11). This will not work on Mac or other platforms.
• Node.js installed on PC with node.exe as part of your %PATH% variable (this happens by default when installing node)

Note: you do NOT need the Logitech Litra software installed for this to work.

Installing

1. git clone https://github.com/mikepaer/litra-automation
2. cd litra-automation
3. npm install

Running

Run launcher-windowless.vbs to start the program.

Note: you can start the program automatically at system boot by creating a shortcut to launcher-windowless.vbs and putting it in your Startup folder.

All launcher-windowless.vbs does is run the node script (node app.js) in a way that suppresses the command prompt.

❗ Important note: the first time you run this script, you may be prompted to install .NET framework. The app will crash without it. Accept the prompt and install it, then re-run the app. This is necessary for the systray aspect of the app.

How this works

Detecting camera use

Windows records when your webcam starts/ends use on a per-app basis to the registry (HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\CapabilityAccessManager\ConsentStore\webcam\*). When the LastUsedTimestamp QWORD value is set to 0x0, that implies the camera is in use.

This app simply polls the registry every 1.5s to see if any LastUsedTimestamp is 0x0 and infers that the webcam is in use. When LastUsedTimestamp changes to anything else, it infers the webcam is no longer in use.

Other libraries in use

• Interfacing with the Litra light: https://github.com/timrogers/litra
• Creating a systray icon and menu: https://github.com/zaaack/node-systray