4) In this problem, you wil investigate a more efficient way to implement spatial filtering when al the filter coefficients have the same value. The motivation comes from the observation that as you slide the filter one pixel at a time over the image and compute the sum-of-products of image and filter values, you can use the results from the previous computation in the current computation Although the method can be generalized, we will consider the case in which all the filter coefficients have the value 1. And, we will also ignore the 12 scaling factor that typically accompanies an averaging filter of size nxn