Moore Neighborhood

The Moore neighborhood of a pixel, P, is the set of 8 pixels which share a vertex or edge with that pixel. These pixels are namely pixels P1, P2, P3, P4, P5, P6, P7 and P8 shown in Figure 1 below.
The Moore neighborhood (also known as the 8-neighbors or indirect neighbors) is an important concept that frequently arises in the literature.

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