www.gusucode.com > wavelet工具箱matlab源码程序 > wavelet/wavelet/orthfilt.m

    function [Lo_D,Hi_D,Lo_R,Hi_R] = orthfilt(W,P)
%ORTHFILT Orthogonal wavelet filter set.
%   [LO_D,HI_D,LO_R,HI_R] = ORTHFILT(W) computes the
%   four filters associated with the scaling filter W 
%   corresponding to a wavelet:
%   LO_D = decomposition low-pass filter
%   HI_D = decomposition high-pass filter
%   LO_R = reconstruction low-pass filter
%   HI_R = reconstruction high-pass filter.
%
%   See also BIORFILT, QMF, WFILTERS.

%   M. Misiti, Y. Misiti, G. Oppenheim, J.M. Poggi 12-Mar-96.
%   Last Revision: 13-May-2003.
%   Copyright 1995-2004 The MathWorks, Inc.

% Check arguments.
if nargin<2 , P = 0; end

% Normalize filter sum.
W = W/sum(W);

% Associated filters.
Lo_R = sqrt(2)*W;
Hi_R = qmf(Lo_R,P);
Hi_D = wrev(Hi_R);
Lo_D = wrev(Lo_R);