THE THEORY OF THE CURVATURE-CONSTRAINT LINE FOR AMODAL COMPLETION

Amodal completion of partly occluded figures is analyzed as natural co mputation. Here amodal completion is shown to consist of four subprobl ems: representation, parsing, correspondence, and interpolation. Secon d, each problem is shown to be basically solvable on the basis of the generic-viewpoint assumption. It is also argued that the interpolation problem might be the key problem because of mutual interdependence am ong the subproblems. Third, a theory is described for the interpolatio n problem, in which the generic-viewpoint assumption and the curvature -consistency assumption are presumed. The generic-viewpoint assumption entails that the orientation and the curvature should not change at t he point of occlusion. The curvature-consistency assumption entails th at the hidden contour should have the minimum number of inflections to maintain continuity in orientation and curvature. The shape of the in terpolated contour represented qualitatively in terms of the number of inflections can uniquely be determined when the location of the termi nators and local orientation and curvature of the visible contours at the terminators are given. Fourth, it is shown in an instant psychophy sics that the theory is highly consistent with human performance.