Relative affine structure: canonical model for 3D from 2D geometry and applications

We propose an affine framework for perspective views, captured by a single extremely simple equation based on a viewer-centered invariant we call relative affine structure. Via a number of corollaries of our main results we show that our framework unifies previous work-including Euclidean, projective and affine-in a natural and simple way, and introduces new, extremely simple algorithms for the tasks of reconstruction from multiple views, recognition by alignment, and certain image coding applications.