www.gusucode.com > 图像变换及频域滤波 空间域图像增强 图像边缘检测源码程序 > digitalimageprocessprograms/sanshi.m

    a=zeros(24,128);
b=[zeros(80,48),ones(80,32),zeros(80,48)];
f=[a;b;a];
subplot(2,1,1);
imshow(f);
h=abs(fft2(f));
subplot(2,1,2);
imshow(h);


figure;
for i=1:128
 for j=1:128
     q(i,j)=(-1)^(i+j).*f(i,j);
 end
end
subplot(2,1,1);
imshow(q);
subplot(2,1,2);
h1=abs(fft2(q));
imshow(h1);


figure;
f0=zeros(128,128);
for x=24:47
    for y=0:(x-24)
        f0(x,81-y)=1;
        f0(x,81+y)=1;
    end
end

for x=81:104
    for y=0:(104-x)
        f0(x,47-y)=1;
        f0(x,47+y)=1;
    end
end

for x=48:80
    for y=0:46
        f0(x,57+y-x+48)=1;
    end
end


for i=1:128
 for j=1:128
     q0(i,j)=(-1)^(i+j).*f0(i,j);
 end
end
subplot(2,1,1);
imshow(q0);

subplot(2,1,2);
h01=abs(fft2(q0));
imshow(h01);