Installing on MacOS
Contributed by Foreman21, tested on MacOS Sonoma 14.6
Since the distributed binaries aren't signed, MacOS will refuse to load them unless you make an excpetion. Note that when you export and sign your project for MacOS or iOS, the godot-ndi binaries will be signed too.

Click cancel
Go to Settings > Privacy & Security

Click
Allow AnywayThe first popup may appear again for a different file from Godot NDI. Click
CancelandAllow Anywayagain

Then click
Open