matlab图像专题;5 图像信息提取和去噪案例程序.zip

close all; clear all; I=imread('rice.tif'); I=im2double(I); u=32; v=32; d=0.3; u1=2*pi*u/256; v1=2*pi*v/256; for j=1:256 for k=1:256 A(j,k)=d*sin(u1*j+v1*k); end end J=I+A; u=45; v=0; u1=2*pi*u/256; v1=2*pi*v/256; for j=1:1:256 for k=1:1:256 A(j,k)=d*sin(u1*j+v1*k); end end J=J+A; u=0; v=45; u1=2*pi*u/256; v1=2*pi*v/256; for j=1:1:256 for k=1:1:256 A(j,k)=d*sin(u1*j+v1*k); end end J=J+A; u=-32; v=32; u1=2*pi*u/256; v1=2*pi*v/256; for j=1:1:256 for k=1:1:256 A(j,k)=d*sin(u1*j+v1*k); end end J=J+A; F1=fft2(I); F1am=abs(F1); F1ph=angle(F1); F11=fftshift(F1); F11am=abs(F11); F2=fft2(J); F2am=abs(F2); F2ph=angle(F2); F22=fftshift(F2); F22am=abs(F22); subplot(2,3,1),imshow(I);title('Original image'); subplot(2,3,2),imshow(J);title('Noisy image'); subplot(2,3,4),imshow(0.25*log10(1+F11am)); subplot(2,3,5),imshow(0.25*log10(1+F22am)); F2am0=F2am(1,1); F2am(1,1)=0; thresh=max(F2am(:)); for j=1:1:256 for k=1:1:256 if F2am(j,k)>thresh/2 F2am(j,k)=0; end end end F2am(1,1)=F2am0; R=F2am.*exp(i*F2ph); R2=fftshift(R); R2am=abs(R2); subplot(2,3,3),imshow(abs(ifft2(R)));title('Result of restoration') subplot(2,3,6),imshow(0.25*log10(1+R2am)); F3am=abs(fftshift(fft2(J))); figure; imshow(0.25*log10(1+F3am));