Re: IMAGE PROCESSING
the most common method is to use Neighborhood Averaging, where you select a mask for how many neighboring pixels to consider. Gaussian smoothing can also be used because it has the attribute that the frequency components of the image are modified in a smooth manner.
You may also use Edge Preserving smoothing because Gaussian smoothing will tend to blur edges. And so median filtering can be used, which is a morphological operation.
To remove noise from images, image restoration method is also useful.