Local affine frames for wide-baseline stereo

A novel procedure for establishing wide-baseline correspondence is introduced. Tentative correspondences are established by matching photometrically normalised colour measurements represented in a local affine frame. The affine frames are obtained by a number of affine invariant constructions on robustly detected, maximally stable extremal regions of data-dependent shape. Several processes for local affine frame construction are proposed and proved affine covariant. The potential of the proposed approach is demonstrated on demanding wide-baseline matching problems. Correspondence between two views taken from different viewpoints and camera orientations as well as at very different scales is reliably established. For the scale change present (a factor more than 3), the zoomed-in image covers less than 10% of the wider view.