MMACH commands


vdiskstr - Generates a disk structuring element


vdiskstr generates special structuring elements which are disks in one of three well-known metrics (2-D case):

_ Euclidean : D(p,q) = sqrt( (px-qx)^2 + (py-qy)^2 )

_ City-Block: D(p,q) = |px-qx| + |py-qy|

_ Chessboard: D(p,q) = max( |px-qx| , |py-qy| )

Disks in each one of the above metrics are respectively circles, diamonds and squares. For a concise review of this subject, see Gonzales & Wintz, "Digital Image Processing", chapter 2.

The disks generated may be planar or nonplanar, 2-dimensional or 3-dimensional. The default is euclidean planar 2-D.

The offset makes sense only for the nonplanar case, in which case the value specified is added to the element. If no offset or 0 is specified, the element values will be adjusted so as to have zero in the borders. For example, a 5x5 chessboard nonplanar 2-D element will look like this: 0 0 0 0 0 0 1 1 1 0 0 1 2 1 0 0 1 1 1 0 0 0 0 0 0

The disk-like structuring elements are very useful in many morphological operations such as distance transforms, granulometry, skeleton algorithms etc.


type: outfile
desc: output resulting struc file definition
type: integer
desc: diameter of the disk to be created
bounds: value > 0
type: boolean
desc: 2D/3D dimension
type: boolean
desc: disk type
type: integer
desc: value to be added to nonplanar elements
bounds: no range checking
type: string toggle
desc: lets user choose which kind of disk is to be created
allowed values:


type: infile
desc: trigger input
default: {none}


vdiskstr -r 3 -t "city-block"
Creates a 2-D disk-like structuring element of radius 3 according to the city-block metric.






Copyright (C) 1993-1997 Junior Barrera, Roberto Lotufo. All rights reserved.