If inpict is a gray scale image, that would apply a median filter to ALL pixels in the image, not just the impulse/salt&pepper noise.
A median filter's claim to fame is that it smooths noisy areas but leaves true edges sharp (it doesn't blur step edges).
If you want a median filter to operate on only salt and pepper noise, you have to
- First median filter the whole image
- Get a mask of the salt and papper noise, where values are either 0 or 255 or whatever values you want to use.
- Replace the original image with the median filtered values but ONLY within the noise mask, not everywhere.
Something like
filteredImage = medfilt2(grayImage, [3,3]);
mask = (grayImage == 0) | (grayImage == 255);
grayImage(mask) = filteredImage(mask);
For a full demo, see my attached demos. For a color image, do it one color channel at a time.
