b) Apply an arithmetic mean filter with a window size of 3 x 3 and 5 x 5 respectively. Compare your results and report the impact of the window size on the visual quality. c) Apply a geometric mean filter to the corrupted image with a window size of 3x3 and 5x5. Compare the result with the one obtained using the arithmetic mean filter. 3. Denoising by Median Filter (40%) a) Download the "img04.jpg" and corrupt the image with a salt-and-pepper noise with Pa=Pb=0.2. b) Apply a median filter ("medfilt2") to the corrupted image. Choose a window size that yields to a better visual quality. Report what window size was chosen. c) Rewrite the "medfilt2" function and test it with the above image.