``Cavity_Deletion'' - delete interior cavities

VFX name:

iCavityDelete

IMPROMPTU Equivalent:

Cavity_Deletion

purpose:

Delete cavities within objects in a binary-valued volume. A cavity is defined as a connected set of 0's that is fully contained within a connected set of 1's.

This operation is done using the following topological operations. First, complement the input volume. Then, perform a 3-D or 2-D connected-components analysis (depending on parameter settings) on the volume, saving only the largest component. Then, complement the volume again.

input:

An 8-bit binary-valued volume.

output:

An 8-bit binary-valued volume.

parameters:

Default parameters menu is

option = 3-D
connectivity = 6

The parameter ``option = '' determines how the cavities are deleted. It toggles between ``3-D'', ``2-D transverse'', ``2-D sagittal'', and ``2-D coronal''. For ``3-D'', all 3-D cavities are deleted. For ``2-D transverse'', all cavities on 2-D transverse planes are deleted, etc.

The option ``connectivity'' toggles between 6 (connectivity) and 26 (connectivity). When one of the 2-D options is selected, 6-connectivity is interpreted as 4-connectivity and 26-connectivity is interpreted as 8-connectivity [24,28,23]. (4-connectivity is the 2-D analog of 6-connectivity, etc.)

comments:

1.

A medium-speed function.

2.

Peculiar things can happen with the 2-D options if you only process small sections of a volume.