Calculate Camera extrinsics from single checkerboard image with known extrinsics

Hello,

I have succesfully calculated my camera intrinsics with the single camera calibration app and now I want to make a position and posture estimation to determine the position of my camera in my setup. For that I have several pictures of a checkerboard, where I precisely measured the position and the orientation of the checkerboard. Now I only need to calculate my camera extrinsics from that images. I don't want to use estimateCameraParameters though, since the intrinsics I already calculated are far more precise. Is there any easy way with Matlab to estimate the extrinsics with known intrinsics or do I have to write the algorithm myself?

Thanks in advance!