Using Points at Infinity for Parameter Decoupling in Camera Calibration
Jean‐Yves Guillemaut, Alberto S. Aguado, John Illingworth · 2002
We consider the problem of decoupling translation and rotation for a collec-tion of 3D data related to 2D images by a projection. The main contribution is to show that equations describing image formation can be decoupled to form a component independent of translation. The decomposition is based on the invariance properties of the projection of points at infinity; if image formation is expressed in terms of points at infinity, general motions can be reduced to pure rotations. Contrary to other methods based on vanishing points, our approach does not require parallel directions to be present in the scene. We use the invariance property to simplify camera calibration equa-tions. We consider three cases for a known calibration object: full calibration, pose estimation and internal calibration by pure translation. Experiments on synthetic and real data show that the decomposition can obtain similar re-sults to a full parameter search. For pure translation, the decomposition can be effectively used to obtain more accurate parameters, without increasing the dimensionality of the problem. 1