WebCamoid Chorma-Key Green Screen Background Image Settings

Can somebody please provide directions on HOW to set up WebCamoid to use a ChromaKey Green Screen to add a virtual background to my virtual camera? I have WebCamoid installed on MacOS Mojave 10.14 but cannot figure out how to do this and I cannot find directions anywhere. In theory I know you need to add an image, add a filter to process the video and then setup WebCamoid as a virtual webcam, but I can find no details on how this is done. Thank you.