A geometric interpretation of weak-perspective motion

We present a geometric interpretation of the problem of motion recovery fro m three weak-perspective images. Our interpretation is based on reducing th e problem of estimating the motion to a problem of finding triangles on a s phere whose angles are known. Using this geometric interpretation, a simple method to completely recover the motion parameters using three images is d eveloped. The results of running the algorithm on real images are presented . In addition, we describe which of the various motion parameters can be re covered already from two images.