similarity.txt

基于平稳双正交小波变换实现图象梯度计算,本人用MATLAB编了一个,供大家参考

clear;
%X=imread('i:\imagedatabase\noname\s1\1.bmp');
X=imread('test.tif');
[lx,ly]=size(X);
X=im2double(X);
[lo_d,hi_d,lo_r,hi_r]= wfilters('bior1.5');
lo_r=dyadup(lo_r,0,length(lo_r)*2);
hi_r=dyadup(hi_r,0,length(lo_r)*2);
[swa,swh,swv,swd]=swt2(X,2,lo_d,hi_d);
dx2=zeros(lx,ly);
for k=1:ly
dx2(:,k)=wkeep(iswt(swv(:,k,2)',swd(:,k,2)',lo_r,hi_r),lx);
end
dy2=zeros(lx,ly);
for k=1:lx
dy2(k,:)=iswt(swh(k,:,2),swd(k,:,2),lo_r,hi_r);
end
colormap(gray);
subplot(2,3,1);image(wcodemat(swv(:,:,2),64));
subplot(2,3,2);image(wcodemat(dx2,64));
subplot(2,3,3);image(wcodemat(swh(:,:,2),64));
subplot(2,3,4);image(wcodemat(dy2,64));
modulus2=abs(dx2+i*dy2);
theta2=angle(dx2+i*dy2);
%modulus2=sqrt(dx2.^2 + dy2.^2);
subplot(2,3,6);image(wcodemat(modulus2,64));
title('modulus');
maxval=max(max(modulus2));
%maxtheta=max(max(theta2));
%mintheta=min(min(theta2));
%temp=zeros(lx,ly,2);
%temp(:,:,2)=modulus2;
%L2=temp<maxval*0.3;
%swa=zeros(lx,ly,2);;
%swh(L2)=0;
%swv(L2)=0;
%swd(L2)=0;
%Y=iswt2(swa,swh,swv,swd,'bior1.5');
%subplot(2,2,3);image(wcodemat(Y,64));;
%subplot(2,2,4);imshow(X);