I have old software which uses a video capture card which is no longer available. The video window built into this software has a purple chroma key and the old card would display the live video on that. I am trying to get the output of a USB camera to display. preferably by chroma key, onto that window. Is there some open source or low cost software available which will allow me to place the live video output onto that chroma key? This would be analogous to replacing the windows desktop with a live video stream, but specific to the purple chroma key in the program. I am open to buying a capture card if I can get software to display into that video window, sort of like the old video blaster card from the 90's

Thanks for any and all help