What data structure to choose for the watershed?

Question

Programming

Hello,
in the watershed and in many other image processing tasks, the task is to compare the value of a pixel with its neighborhood once. A quick search brought me only a naive solution: we go through the array, at each iteration of the inner loop we form a neighborhood, we compare. Can you suggest solutions with fewer comparisons and more frequent cache hits?

Answer 1

A ray from a pixel to a given radius rotated by 3 unequal acyclic angles.