add salt and pepper noise to figure 2 with probabilities pa = pb = 0.2. try to remove the noise by applying a 3 x 3 median filter to the noisy image. in matlab

To add salt and pepper noise to an image in Matlab, you can use the imnoise function.

main.m
img = imread('figure2.png'); % Load the image
noisy_img = imnoise(img, 'salt & pepper', 0.2); % Add salt and pepper noise with probability 0.2
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To remove the noise, we can use a median filter. The median filter replaces each pixel value with the median value of its neighboring pixels. This is effective at removing salt and pepper noise, because the noisy pixels are often outliers and will have much higher or much lower values than their neighbors.

main.m
median_filtered_img = medfilt2(noisy_img, [3 3]); % Apply a 3 x 3 median filter to the noisy image
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Note that the size of the filter ([3 3] in this case) can be adjusted depending on the amount of noise and the level of detail in the image.

Finally, we can display the original image, the noisy image, and the filtered image side-by-side for comparison.

main.m
figure;
subplot(1,3,1); imshow(img); title('Original Image');
subplot(1,3,2); imshow(noisy_img); title('Noisy Image');
subplot(1,3,3); imshow(median_filtered_img); title('Filtered Image');
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This will create a figure with three subplots, showing the original image, the noisy image, and the filtered image.