www.gusucode.com > matlab编程NSCT分解 图像融合 各个融合指标评价体系 分解源码程序 > matlab编程NSCT分解 图像融合 各个融合指标评价体系 分解源码程序/NSCT/ld2quin.m
function [h0, h1] = ld2quin(beta) % LD2QUIN Quincunx filters from the ladder network structure % % Construct the quincunx filters from an allpass filter (beta) using the % ladder network structure % % Ref: Phong et al., IEEE Trans. on SP, March 1995 if all(size(beta) ~= 1) error('The input must be an 1-D fitler'); end % Make sure beta is a row vector beta = beta(:)'; lf = length(beta); n = lf / 2; if n ~= floor(n) error('The input allpass filter must be even length'); end % beta(z1) * beta(z2) sp = beta' * beta; % beta(z1*z2^{-1}) * beta(z1*z2) % Obtained by quincunx upsampling type 1 (with zero padded) h = qupz(sp, 1); % Lowpass quincunx filter h0 = h; h0(2*n, 2*n) = h0(2*n, 2*n) + 1; h0 = h0 / 2; % Highpass quincunx filter h1 = -conv2(h, h0); h1(4*n-1, 4*n-1) = h1(4*n-1, 4*n-1) + 1;