www.gusucode.com > 基于matlab编程Contourlet变换在图像检索源码程序 > code1/基于matlab编程Contourlet变换在图像检索源码程序/code/NSCT-SF-PCNN-ImageFusion-Toolbox/SF.m
function cp=SF(matrix) % Compute the spatial frequency (SF) of image or subbbands of NSCT. % --------- % Author: Qu Xiao-Bo <quxiaobo <at> xmu.edu.cn or qxb_xmu@yahoo.com.cn> Aug.28,2008 % Postal address: % Room 509, Scientific Research Building # 2,Haiyun Campus, Xiamen University,Xiamen,Fujian, P. R. China, 361005 % Website: http://quxiaobo.8866.org or http://quxiaobo.go.8866.org %============================================================= disp('SF is computing...') [row,column]=size(matrix); cp=zeros(row,column); window_wide=3; spread=(window_wide-1)/2; matrix_en=padarray(matrix,[spread spread],'symmetric'); temp=matrix_en.*0; for i=1:row for j=1:column temp(i,j)=((matrix_en(i+1,j+1)-matrix_en(i+1,j))^2+(matrix_en(i+1,j+1)-matrix_en(i,j+1))^2); end end for i=1:row for j=1:column window=temp(i:1:(i+2*spread),j:1:(j+2*spread)); cp(i,j)=sqrt(sum(window(:))./(window_wide.^2)); end end