Spatial filtering is a form of finite impulse response (FIR) filtering. The filter is actually a mask of weights arranged in a rectangular pattern. The process is one of sliding the mask along the image and performing a multiply and accumulate operation on the pixels covered by the mask.
In this lecture we will talk about ordered statistical filters and median filter will be introduced. First and second ordered differential filters such as Gradient and Laplacian will be introduced. We will get to know how Sobel operator is working.
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