Linear Pushbroom Cameras

Abstract

Modelling and analyzing pushbroom sensors commonly used in satellite imagery is difficult and computationally intensive due to the motion of the orbiting satellite with respect to the rotating earth, and the non-linearity of the mathematical model involving orbital dynamics. The linear pushbroom model) introduced in this paper has the advantage of computational simplicity while at the same time giving very accurate results compared with the full orbiting pushbroom model. The common photogrammetric problems may be solved easily for the linear pushbroom model. The linear pushbroom model leads to theoretical insights that are approximately valid for the full model as well. The epipolar geometry of a linear pushbroom camera is different from that of a perspective camera. Nevertheless, a matrix analogous to the fundamental matrix of perspective cameras is shown to exist for linear pushbroom sensors. From this it is shown that a scene is determined up to an affine transformation from two views with linear pushbroom cameras.