Hardware manual

Impact Reference Guide Morphology Close
3-53 Datalogic Automation Inc.
Dilate
The dilate operation gradually enlarges the boundaries of regions of foreground pixels. Thus areas of fore-
ground pixels grow in size while holes (background pixels) within those regions become smaller.
Erode
The erode operation erodes away the boundaries of regions of foreground pixels. Thus areas of foreground
pixels shrink in size, and holes within those areas become larger.
Open
The open operation is similar to erosion in that it tends to remove foreground (bright) regions in an image,
but it less destructive than erosion in general. The effect is to preserve foreground regions that have a similar
shape while eliminating all other regions of foreground pixels. It is defined as an erosion followed by a dila-
tion.
Morphology Shape
Morphology Shape defines the shape of the neighborhood around each pixel that is searched to find the out-
put pixel value. It is sometimes referred to as structuring element, filter mask, or filter kernel. The choices
are Square and Octagon.
A square morphology shape is the fastest to process, but has the disadvantage of working better in the diag-
onal directions than in the horizontal and vertical directions. In the example shown below (the figure on the
left), a Morphology Erode tool is used to test the size of a fifty-pixel radius circular hole. With a square mor-
phology shape, the tool tests all pixels in a 100x100 square, centered on the hole. However, the number of
Results of a dilate
operation
Results of an
erode operation
Results of an open
operation