a contour based image retrieval algorithm is proposed for improving the algorithm proposed by Choi Wai pak et al
in which the shape of an object is represented based on the normalized maximal disks. In order to generate a simpler and smoother contour
the one dimensional Gaussian functions of two different scales are employed respectively for the concave and convex part of the contour in the proposed algorithm. Additionally
the skeleton of the contour is extracted by a skeletonization algorithm. Finally
the histogram of the distances between the evolved contour and skeleton is used to describe the shape for the retrieval purpose. As compared with the original algorithm that uses only the skeleton of an object
the algorithm proposed uses not only the contour that represents the shape of an object from outer but also the skeleton that preserves the original objects topology from inner. Experimental results show that the new algorithm proposed here outperforms that proposed by Choi Wai pak et al. in the robustness to the scaling