Basic Concepts of Grey‑Scale Morphology

This document describes the morphological operations dilation, erosion, opening, and closing, as applied to grey‑scale images. In general, dilation enlarges the size of light objects in an image, and erosion reduces their size. Opening fills gaps between close light objects in an image, and closing eliminates small light dots and thin lines. Note that in this chapter, the term light means “having relatively higher grey‑scale values than that of background areas” and object and feature refer to areas of light pixels.

When performing a grey‑scale morphological operation, you specify a source image, a morphological structuring element, and a destination image.

The source image is the image on which the morphological operation is to be performed. The destination image contains the result of the morphological operation. The morphological structuring element, which is used to calculate the result, is described below.