“…image retrieval, object classification, object recognition, object identification, etc). Different mathematical tools have been used to define the shape descriptors: algebraic invariants [14], Fourier analysis [6], morphological operations [26], integral transformations [23], statistical methods [17], fractal techniques [15], logic [27], combinatorial methods [1], multiscale approaches [9], integral invariants [16], multi-scale integral geometry [3,4,18], etc. Generally speaking, shape descriptors can be classified into two groups: area based descriptors and boundary based ones.…”