I would like to add some information about homogeneous transformations and camera sensors.
These are classical topics in pose estimation in computer vision or in robotics.
I think the calib3d contains already some useful information and improving this section can benefit to users, beginners, can be a good reference for learners since OpenCV is heavily used.

Added info:

Some links:

• a free Robotics book: 3.3.1. Homogeneous Transformation Matrices
• the inspiration for the figure: https://github.com/tjiiv-cprg/EPro-PnP-v2

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