Thinning (morphology)

Thinning is the transformation of a digital image into a simplified, but topologically equivalent image. It is a type of topological skeleton, but computed using mathematical morphology operators.

Let ${\displaystyle E=Z^{2}}$, and consider the eight composite structuring elements, composed by:

and the three rotations of each by ${\displaystyle 90^{o}}$, ${\displaystyle 180^{o}}$, and ${\displaystyle 270^{o}}$. The corresponding composite structuring elements are denoted ${\displaystyle B_{1},\ldots ,B_{8}}$.

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