Affine integral invariants for extracting symmetry axes

摘要

In this paper, we propose integral invariants based on group invariant parameterisation. The new invariants do not suffer from occlusion problems, do not require any correspondence of image features unlike existing algebraic invariants, and are less sensitive to noise than differential invariants. Our framework applies affine differential geometry to derive novel affine integral invariants. The new in-variants are exploited for extracting the symmetry axes of planar objects viewed under weak perspective. The proposed method is tested on natural leaves and is shown to extract symmetry axes reliably.