You need to construct a special video, see:
https://github.com/m90/seeThru
https://github.com/hawksley/Threex.chromakey
https://vampire.rip/alphaVideo/
(Video from Here)
You need to construct a special video, see:
https://github.com/m90/seeThru
https://github.com/hawksley/Threex.chromakey
https://vampire.rip/alphaVideo/
(Video from Here)