Critical motion sequences for the self-calibration of cameras and stereo systems with variable focal length

摘要

We consider the self-calibration problem for a moving camera whose intrinsic parameters are known except for the focal length which may vary freely across different views. The conditions, under which the determination of the focal length's values for an image sequence is not possible, are derived. These depend only on the camera's motion. We give a complete catalogue of the so-called critical motion sequences. This is then used to derive the critical motion sequences for stereo systems with variable focal lengths.