Various Shape Descriptors in Image Processing ? A Review

Images have different features associated to them. Shape is an important visual feature in an image. It plays a vital role in Content Based Image Retrieval (CBIR). There are many shape descriptors that can be used in image processing. This paper presents a study on different shape descriptors. We have reviewed the contour based shape descriptors like Fourier Descriptors, Curvature Scale Space Descriptors and region based shape descriptors like Angular Radial Transform (ART), Image Moment Descriptors, Zernike Moments descriptors (ZMD), Geometric Moments Descriptors (GMD) and Grid Descriptors (GD). The advantages and disadvantages of these shape descriptors are also discussed.