This function counts the number of neighboring/touching pixels in a 2D binary image

This function counts the number of neighboring/touching pixels in a 2D binary image

Arguments

im

A boolean matrix representing a binary image

diagonal

Whether to count diagonal elements as valid neighbors

Value

A matrix of the same size as im containing the number of neighboring pixels

Details

This is an internal function used by geom_outline to clean up outlines

Author

Michael Hallquist