Spatial calibration method

A non-transitory computer-readable medium carrying a computer program to execute a method for spatial calibration of a first image against a second image, the method comprising:

• obtaining a plurality of pairs of points of interest, each pair matching a point of interest in the first image to a corresponding point of interest in the second image;
• determining, iteratively, a projection model between the first and second images using pairs of points of interest of the obtained plurality;
• and
• calibrating the first image based on the determined projected model;
• wherein an iteration of the determining comprises:
• displacing a position of a point of interest;
• determining a projection model candidate using multiple pairs of points of interest, the multiple pairs including the point of interest with the displaced position;
• and
• evaluating a reprojection error between the positions of the points of interest as projected using the projection model candidate and the corresponding points of interest;
• wherein the projection model is determined by choosing a projection model candidate based on the evaluated reprojection errors associated with a plurality of projection model candidates.