Design of linear-phase nonsubsampled nonuniform directional filter bank with arbitrary directional partitioning

摘要

In this paper, we propose a design method for linear phase (LP) nonsubsampled nonuniform directional filter bank (NUDFB) with arbitrary number of subbands and arbitrary directional partitioning. The proposed NUDFB is simply designed by windowing the analytical expressions of wedge-shaped filters in space domain. The direction and angular bandwidth of the filters are determined by only two angular parameters. It can extract directional information according to the directional distribution of images, making it efficient in the directional representation of images. In addition, the perfect reconstruction conditions are derived. Numerical experiments on image directional information extraction and image denoising are given to illustrate the performance of our NUDFB. The results show that our NUDFB outperforms various directional decomposition methods while possesses LP property and more flexibility.