Design for two dimensional LP-NPR filter banks based on cosine modulation
Xiaolong Wang · Computer Engineering and Applications Journal · 2009
Two dimensional filter banks are usually applied to image processing.Linear Phase(LP) property of filter banks is al- so desired in sub-band image coding.In this paper,a design method of two dimensional Linear Phase Nearly Perfect Reconstruc- tion (LP-NPR) filter banks based on a new class of cosine modulation systems is presented,which can be described as follow: firstly,the Parks-McClellan algorithm is adopted for designing the prototype filter,then by employing cosine modulation,a series of analysis and synthesis filters can be obtained,accordingly a one-dimensional LP-NPR filter banks can be constructed;Secondly, cascading two one-dimensional LP-NPR filter banks in the form of tree structure and using the unimodular transformation,a two dimensional nonseparable LP-NPR filter banks can be obtained.Experimental results indicate the proposed method is feasible,and the designed filter banks can obtain the satisfying reconstructive precision.