Remove periodic Noise and convert photo to RGB again

Here i have an image with periodic noise and i want to convert it to frequency domain using Fourier transform and apply notch filter to remove noise and then inverese fourier transform to get image to spatial domain again and convert it to RGB image again. Here is my code for that but i just convert image to frequence domain and apply filter but doesn't work and after that inverese fourier transform to convert image to spatial domain but can't convert it to RGB and just saw image without colors.

f = im2double(rgb2gray(imread('Moire2.bmp')));
imshow(f), title('Original Image'); 
F = fft2(f);

%create filter for noise removal but doesn't work and need changes 
H = ones(size(f));
x = 10;
H(165-x:169+x, 127-x:131+x) = 0;
H(170-x:174+x, 61-x:65+x) = 0;
H = ifftshift(H);
% apply your own filter to image 
filtered = F .* H;
figure, imshow(filtered) , title('Filter');
% inverse fourier trensform to restore image to spatial Domain again and i want to convert it to RGB image but can't do that
f1 = ifft2(filtered);
figure, imshow(f1), title('Restored Image'); 

[Johannes Fischer]

Right in you first line you remove your color information by calling rgb2gray. How do you expect to retrieve color data after that?

You will need to perform your filtering for each of the three color channels separately and combine the three channels back to one RGB matrix.

Looking at the image, I also think that your filter must be adapted for each color channel.

[KALYAN ACHARJYA]

Absolutely correct way for gray images. Image>FFT>>Notcg>IFT

I have done the same with gray images, I didnot try with RGB yet.

[Bjorn Gustavsson]

Just to add to Johannes' comment: Try this to get a grip on the different colour-components:

subplot(3,2,1)
imagesc(Im1(:,:,1))                  
subplot(3,2,2)
imagesc(log10(abs(fft2(Im1(:,:,1)))))
subplot(3,2,3)
imagesc(Im1(:,:,2))                  
subplot(3,2,4)
imagesc(log10(abs(fft2(Im1(:,:,2)))))
subplot(3,2,5)
imagesc(Im1(:,:,3))                  
subplot(3,2,6)
imagesc(log10(abs(fft2(Im1(:,:,3)))))

Then you'll see the intensity in each colour-plane and the corresponding FFT - you might consider throwing in a call to fftshift as well to get the DC-component in the centre to help your manual inspection along.

[Ahmed Emad]

But image still have periodic noise and filter doesn't work correctly , So please help me to remove periodic noise and don't care about convert to RGB now because the main purpose of my question is to remove periodic noise using Notch filter and i can't do that correctly KALYAN ACHARJYA Bjorn Gustavsson Johannes Fischer