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/symext.m
function yT=symext(x,h,shift); % FUNCTION Y = SYMEXT % INPUT: x, mxn image % h, 2-D filter coefficients % shift, optional shift % OUTPUT: yT image symetrically extended (H/V symmetry) % % Performs symmetric extension for image x, filter h. % The filter h is assumed have odd dimensions. % If the filter has horizontal and vertical symmetry, then % the nonsymmetric part of conv2(h,x) has the same size of x. % % Created by A. Cunha, Fall 2003; % Modified 12/2005 by A. Cunha. Fixed a bug on wrongly % swapped indices (m and n). [m,n] = size(x); [p,q] = size(h); parp = 1-mod(p,2) ; parq = 1-mod(q,2); p2=floor(p/2);q2=floor(q/2); s1=shift(1);s2=shift(2); ss = p2 - s1 + 1; rr = q2 - s2 + 1; yT = [fliplr(x(:,1:ss)) x x(:,n :-1: n-p-s1+1)]; yT = [flipud(yT(1:rr,:)); yT ; yT(m :-1: m-q-s2+1,:)]; yT = yT(1:m+p-1 ,1:n+q-1);