clear;load clown;FX=fft2(X);L=4;WMAX=100/L;
FX(WMAX+2:200-WMAX,:)=0;FX(:,WMAX:200-WMAX)=0;X=real(ifft2(FX));
figure,imagesc(X),colormap(gray),axis off %L=2,4,5,10.
figure,imagesc(fftshift(log10(abs(FX)))),colormap(gray),axis off
Y=X(1:L:200,1:L:200);Z(200,200)=0;Z(1:L:200,1:L:200)=Y;
FZ=fft2(Z);FW=FZ;
figure,imagesc(Z),colormap(gray),axis off
figure,imagesc(fftshift(log10(abs(FZ)))),colormap(gray),axis off
FW(WMAX+2:200-WMAX,:)=0;FW(:,WMAX+2:200-WMAX)=0;W=real(ifft2(FW))*L*L;
figure,imagesc(W),colormap(gray),axis off
figure,imagesc(fftshift(log10(abs(FW)))),colormap(gray),axis off
