A flexible directional image representation using pseudo polar fourier transform based DFBs

This paper presents a kind of basis functions used for image directional representation, which are obtained from the pseudo polar Fourier transform-based directional filter banks (PPFT-DFBs). The basis functions so obtained have the attractive properties of i) flexible direction and ii) arbitrary number of subbands. More specifically, we give the derivation of the basis function from the equivalent directional filter of PPFT-DFBs. Further, we analyze the properties of basis functions and their corresponding basis images. Experiments are given to testify the flexibility of basis functions and their efficiency in directional representation.