low pass filter for image analysis

I am doing low pass filtering of an image.After applying mask and I need to get filtered image but instead I am getting I6 as attached. I have tried with different mask sizes but still unable to get the same image back with low frequency content. Can you plz check the code and point the mistake in code or methodology.

Thanks in advance,

if true
  % code
clc
close all
clear all
I1 = imread('C:\User\Desktop\taken\s3.jpg');
I1 = imresize(I1,[128 128]);
I2 = rgb2gray(I1)
I2=double(I2);
figure, imshow(uint8(I2));
I3=fft2(I2);
I3=fftshift(I3);
figure
I4=log(1+abs(I3));
imshow(mat2gray(I4));
[r,c]=size(I2);
orgr=r/2;
orgc=c/2;
mf= zeros(r,c);
D0= 40;
for i=1:r
  for j=1:c
      if((i-orgr)^2+(j-orgc)^2)^(0.5)<=D0
          mf(i,j)=1;
      end
  end
end
figure
imshow(uint8(255*mf));
title('frequency domain filter used');
I5=I3*mf;
figure,
I4=log(1+abs(I5));
imshow(mat2gray(I4));
title('filtered image in frequency domain');
I6=ifft2(ifftshift(I5));
figure,
imshow(uint8(abs(I6)));
title('filtered gray scale image');
end

Answer 1

[Jordan Ross]

Hi,

It seems you have an error in your code. The following line:

I5=I3*mf;

Should be:

I5=I3.*mf;

After making this change I was able to retrieve the image back (see the attached file).

[Snowleopard]

Thanks