s103.m

简单的数字图像处理程序

% 灰度图像频域函数变换伪彩色显示  s103
clear;
I103=imread('2.jpg');
Gray=rgb2gray(I103);
F=im2double(Gray);
G=fft2(F);
G=fftshift(G);
[m,l]=size(G);
N1=fix(m/2);       %fix:向零取整
N2=fix(l/2);        %fix:向零取整
for i=1:m
    for j=1:l
        d=sqrt((i-N1)^2+(j-N2)^2);
       if d<5
           a1(i,j)=G(i,j);
           [m1,l1]=size(a1);
           for p=m1:m
               for q=l1:l
                   a1(p,q)=0;
               end
           end
       elseif d<10
           a2(i,j)=G(i,j);
           [m2,l2]=size(a2);
           for p=m2:m
               for q=l2:l
                   a2(p,q)=0;
               end
           end
       else
           a3(i,j)=30*G(i,j);
       end
    end
end
a11=ifftshift(a1);
x1=ifft2(a11);
x4=im2uint8(real(x1));
a22=ifftshift(a2);
x2=ifft2(a22);
x5=im2uint8(real(x2));
a33=ifftshift(a3);
x3=ifft2(a33);
x6=im2uint8(real(x3));
figure;imshow(cat(3,x4,x5,x6))