Setting camera intrinsics from 3x3 matrix

Hi

Hard one to explain here but I’ll give it a go…

I’m trying to use the OpenCV calibrateCamera function to calculate the required pose and properties needed to add to a camera to get its output to align to that of a 2d image.

I’m collecting all the correct info to send to the calibrateCamera function (2d points, corresponding 3d points etc) and the function’s returning the correct properties for aligning the camera - extrinsic properties such as rotation and transform vectors for aligning the camera and intrinsic properties in the form of a 3x3 matrix. The intrinsic properties are basically the focal lengths (fx & fy) and the ‘principal point offset’ of the camera (cx & cy)

I don’t know how to apply these properties to a camera in openFrameworks. It doesn’t look like there’s a matrix I can apply these to directly. Can anyone point me in the right direction please?

I can easily provide more info if needed.

Thanks loads for any help on this - massively stuck at the mo!