3D structure recovery and errors on the intrinsic parameters

This paper addresses the problem of computing the Euclidean 3D structure of an observed scene. Given at least 2 images with pixel correspondences, the 3D structure of the scene and the motion of the camera (translation and rotation) are calculated simultaneously. We study here the effect of inaccurate intrinsic parameters on the quality of the recovered reconstruction. Classical methods based on the essential matrix computation have proven to be very unstable when the intrinsic parameters of the cameras are not known exactly. To overcome such unstability, we used a method where a particular choice of a 3D Euclidean coordinate system with a different parameterization of the motion/structure problem allowed us to reduce significantly the total number of unknowns. In addition, the simultaneous calculation of the camera motion and the 3D structure has made the computation of the motion and structure less sensitive to the errors in the values of the intrinsic parameters of the camera. Experiments with real images validated our method and experiments with simulated data showed how the errors on the intrinsic parameters affect the accuracy of the reconstruction