Abstract

General multi view reconstruction from afine or pro jective cameras has so far been solved most eficiently using methods of factorizing image data matrices into camera and scene parameters. This can be done directly for afine cameras [18] and after computing epipolar geometry for pro jective cameras [17]. A notorious problem has been the fact that these factorization methods require all points to be visible in all views. This paper presents alternative algorithms for general afine and pro jective views of multiple points where a) points and camera centers are computed as the nullspace of one linear system constructed from all the image data b) only three points have to be visible in all views. The latter requirement increases the fiexibility and usefulness of 3D reconstruction from multiple views. In the case of pro jective views and unknown epipolar geometry, an additional algorithm is presented which initially assumes afine views and compensates iteratively for the perspective efiects. In this paper afine cameras are represented in a pro jective framework which is novel and leads to a unified treatment of parallel and perspective pro jection in a single framework. The experi- ments cover a wide range of difierent camera motions and compare the presented algorithms to factorization methods, including approaches which handle missing data.