ORE DIFFERENTIAL INVARIANTS OF PLANAR CURVES AND RECOGNIZING PARTIALLY OCCLUDED PLANAR SHAPES

Viewing transformations like similarity, affine and projective maps ma y distort planar shapes considerably. However, it is possible to assoc iate local invariant signature functions to smooth boundaries that ena ble recognition of distorted shapes even in the case of partial occlus ion. The derivation of signature functions, generalizing the intrinsic curvature versus are-length representation in the case of rigid motio ns in the plane, is based on differential invariants associated to vie wing transformation.