Calculation 4x4 matrix of camera

Hi everyone! I have World Frame. I have diodes and I know coordinates of them (X,Y,Z) in this World Frame. I have camera, which takes pictures. I need to calculate matrix 4x4 of camera in World Frame. Which function of OpenCV should I use? How many diodes do I need? I need full matrix 4x4 (X,Y,Z + RotMatrix 3x3).