How to get image/video from any camera to process it in real time with OpenCV?

I have an actor with two SceneCapture2D cameras. Ive made render targets out of them but couldnt find any possible way of saving or getting access to them in real-time.
The question is: What are the possible variants of getting images of a part of the scene and what are the functions and elements needed?

Hi, I’m trying to do the same in UE 4.24…
Have you solved?