How to remove gaussian noise?
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Hello, I'm working on image encryption. I need to see how well my encryption is so i thght of adding noise and testing it.I added gaussian noise with the following code.My problem is i dont know how to remove it before applying decryption algorithm.i get decimal values, I want to get whole numbers in the resulting matrix.
I=imread('leena.bmp');
M =0;
V=0.01;
imshow(I);
title('Original Image');
J = imnoise(I,'gaussian',M,V);
figure,imshow(J);
title('Gaussian Noise');
i'm planning to add other noises as well like poisson noise, speckle noise and salt and pepper noise. Is there any possibility that a code exists for removing all these noises separately? please help..thanks in advance
Accepted Answer
Image Analyst
on 1 Nov 2014
For Gaussian noise, the maximum likelihood de-noised answer would just be a local mean, which you can do with conv2():
denoisedImage = conv2(double(noisyImage), ones(3)/9, 'same');
If you want to do Salt and Pepper noise, then see my attached demos where I use a modified median filter.
12 Comments
Image Analyst
on 13 Aug 2020
If you check the documentation you'll see that it's the window size of the window that scans across the image.
More Answers (1)
lakpa tamang
on 15 Dec 2019
Image Analyst.. can you explain how does the denoising works actually.. mathamatically?
3 Comments
RAJSHREE SRIVASTAVA
on 28 Dec 2020
Image analyst , I am trying to excute the last file of
But I am getting error : salt_and_pepper_noise_removal_grayscale
Undefined function or variable 'salt_and_pepper_noise_removal_grayscale'.
Please do help
Image Analyst
on 28 Dec 2020
How are you trying to run it? Is it open in the editor window? Did you click the green run triangle? Then it will run. I just ran it again to make sure everything works fine, and it does.
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