This paper tackles the problem of the quadric mirror estimation of omnidirectional imaging systems, aswell as the poses of the camera relative to the mirror and to the world reference system. These estimates areobtained for quadric-shaped mirrors (including elliptic, parabolic, hyperbolic and spherical mirrors) wherethe position of the camera and mirror is unconstrained (fully non central configurations). The apparentcontour of the mirror can be used to reduce the uncertainty in the estimation. Although it can enhanceboth the accuracy of the estimation (allowing the method to converge from farther initial configurations)and also its performance, its use is not strictly required. The intrinsic parameters of the camera model(pinhole or orthographic) are assumed to be known as well as the structure of a calibration object in localcoordinates. The method is nonlinear and we use a genetic algorithm in conjunction with the Nelder-Meadsimplex algorithm to minimize the objective function. Experimental results using real data are presenteddemonstrating the accuracy of this calibration method, comparing accuracy with and without the apparentcontour and computing the reprojection error. As the mirror quadric is estimated, this method can also beused to identify and classify the mirror.
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