Multi-scale contour flexibility shape signature for Fourier descriptor

Shape signature and Fourier descriptor are common techniques for shape description and they are widely used in pattern recognition and computer vision applications. In this paper, a novel shape signature is proposed, namely, multi-scale contour flexibility shape signature. After the discrete Fourier transform is performed on the multi-scale contour flexibility shape signature, the Fourier descriptor will be obtained. As a contour line function, contour flexibility based Fourier descriptor not only describes the whole deformation characteristics of the two dimensional shape profiles, but also reflects the local deformation characteristics of the contour sampling points. Thus, the proposed method incorporates the global and local features of the shape. Multi-scale technique could solve the problem of elastic parameter selection skillfully and describe the shape features from coarse to fine. In addition, contour flexibility is also easy to be calculated. Experiments conducted in the MPEG-7 shape database show that the best retrieval results are achieved by the multi-scale contour flexibility based Fourier descriptor compared with other representative shape signatures based Fourier descriptor.