untitled5.m

matlab 例程

X=imread('lena.bmp'); %装载图像信号
whos
figure(1);
imshow(X);  %显示图像
X=im2double(X);
init=2788605826;
rand('seed',init); Xnoise=X+0.2*(rand(size(X)));
figure(2);
image(wcodemat(Xnoise,192)); colormap(map);
[C,S] = wavedec2(Xnoise,2,'db3'); %图像的多尺度二维小波分解
cA2 = appcoef2(C,S,'db3',2); %从上面的C中提取第二层的低频系数
cA1 = appcoef2(C,S,'db3',1); %从上面的C中提取第一层的低频系数
cH2 = detcoef2('h',C,S,2); %从上面的C中提取第1、2层的高频系数,或采用[cH2,cV2,cD2] = detcoef2('all',C,S,2);[cH1,cV1,cD1] = detcoef2('all',C,S,1);
cV2 = detcoef2('v',C,S,2);
cD2 = detcoef2('d',C,S,2);
cH1 = detcoef2('h',C,S,1);
cV1 = detcoef2('v',C,S,1);
cD1 = detcoef2('d',C,S,1);
A1 = wrcoef2('a',C,S,'db3',1); %A1 = wrcoef2('a',C,S,'bior3.7',1);
A2 = wrcoef2('a',C,S,'db3',2); %A2 = wrcoef2('a',C,S,'bior3.7',2);
H1 = wrcoef2('h',C,S,'db3',1); %重构第1、2层的高频信号
V1 = wrcoef2('v',C,S,'db3',1);
D1 = wrcoef2('d',C,S,'db3',1);
H2 = wrcoef2('h',C,S,'db3',2);
V2 = wrcoef2('v',C,S,'db3',2);
D2 = wrcoef2('d',C,S,'db3',2);
A1=edge(A1,'canny');
H1=edge(H1,'sobel');
V1=edge(V1,'sobel');
D1=edge(D1,'sobel');

A2=edge(A2,'canny');
H2=edge(H2,'sobel');
V2=edge(V2,'sobel');
D2=edge(D2,'sobel');

figure(3);
subplot(2,4,1);image(wcodemat(A1,192));colormap(map);
title('Approximation A1')
subplot(2,4,2);image(wcodemat(H1,192));
title('Horizontal Detail H1')
subplot(2,4,3);image(wcodemat(V1,192));
title('Vertical Detail V1')
subplot(2,4,4);image(wcodemat(D1,192));
title('Diagonal Detail D1')
subplot(2,4,5);image(wcodemat(A2,192));
title('Approximation A2')
subplot(2,4,6);image(wcodemat(H2,192));
title('Horizontal Detail H2')
subplot(2,4,7);image(wcodemat(V2,192));
title('Vertical Detail V2')
subplot(2,4,8);image(wcodemat(D2,192));
title('Diagonal Detail D2')
figure(6);
image(wcodemat(A2,192));colormap(map);
title('A2');
Xnoise1=edge(Xnoise,'canny');
figure(5);
image(wcodemat(Xnoise1,192));colormap(map);
title('Xnoise canny');