2-D shape representation using improved Fourier descriptors

Fourier descriptors (FD´s) are widely used shape descriptors. By first warping the scanning speed of the contour before calculating the FD´s, the shape approximation can be improved. This approach has never been properly tested on real applications. In this paper we compare these new shape descriptors to the regular FD´s. A database of over 400 leaf shapes is approximated using these shape descriptors and compared to the approximation based on FD´s. The error of the approximation was measured with the Hausdorff distance and modified Hausdorff distance, resulting for both criteria in an average improvement of more than 10% over approximation based on FD´s.