LINEAR PUSHBROOM CAMERAS

Modeling and analyzing pushbroom sensors commonly used in satellite im agery is difficult and computationally intensive due to the motion of an orbiting satellite with respect to the rotating earth, and the nonl inearity of the mathematical model involving orbital dynamics. in this paper, a simplified model of a pushbroom sensor (the linear pushbroom model) is introduced. It has the advantage of computational simplicit y while at the same time giving very accurate results compared with th e full orbiting pushbroom model. Besides remote sensing, the linear pu shbroom model is also useful in many other imaging applications. Simpl e noniterative methods are given for solving the major standard photog rammetric problems for the linear pushbroom model: computation of the model parameters from ground-control points; determination of relative model parameters from image correspondences between two images; and s cene reconstruction given image correspondences and ground-control poi nts. The linear pushbroom model reads to theoretical insights that are approximately valid for the full model as well. The epipolar geometry of linear pushbroom cameras in investigated and shown to be totally d ifferent from that of a perspective camera. Nevertheless, a matrix ana logous to the fundamental matrix of perspective cameras is shown to ex ist for linear pushbroom sensors. From this it is shown that a scene i s determined up to an affine transformation from two Views with linear pushbroom cameras.