A General Expression of the Fundamental Matrix for Both Perspective and Affine Cameras

Abstract

This paper addresses the recovery of structure and motion from two uncalibrated images of a scene under full perspective or under affine projection. Epipolar geometry, projective reconstruction, and affine reconstruction are elaborated in a way such that everyone having knowledge of linear algebra can understand the discussion without difficulty. A general expression of the fundamental matrix is derived which is valid for any projection model without lens distortion (including full perspective and affine camera). A new technique for affine reconstruction from two affine images is developed, which consists in first estimating the affine epipolar geometry and then performing a triangulation for each point match with respect to an implicit common affine basis. This technique is very efficient.