lvm180(3)

LIBRARY ROUTINE
lvm180 - computes a 180 degree rotation of a morphological kernel.

LIBRARY CALL
#include "vinclude.h"
int
lvm180(kernel)
struct xvimage *kernel;

INPUT

    1. kernel - pointer to an xvimage (morphological kernel) It is strongly advisable to use a kernel created with vmcustom.

OUTPUT
1. kernel - holds the resulting rotated kernel

MODIFICATIONS
Ghosted by Pascal ADAM Fri May 25 14:05:41 MDT 1990

DESCRIPTION
vm180 computes a 180 degree rotation of a morphological kernel.

From a general scientific perspective, the word MORPHOLOGY refers to the study of form and structure.

The morphological approach is generally based upon the analysis of a two-valued image in terms of some predetermined geometric shape known as a structuring element. Essentially, the manner in which the structuring element fits into the image is studied.

The morphological operations can be employed for many purposes, including edge detection, segmentation, and enhancement of images.

A Morpho-kernel is characterized by:

    kernc : number of columns
    kernr : number of rows
    starti : upper left hand corner x_coordinate
    startj : upper left hand corner y_coordinate

The rotated kernel is characterized by:

    new_kernc = kernc
    new_kernr = kernr
    new_starti = -(starti+kernr)
    new_startj = -(startj+kernc)

Relation between the original and rotated kernel:

    kernel(i) = new_kernel(kernc*kernr -1 -i)
    for i between 0 and (kernc*kernr-1)

SET OF MORPHOLOGICAL FUNCTIONS:

vm180 is one of the morphological functions available.

vmcustom:
    Customizes a structuring element

vmerode:
    Erosion

vmdilate:
    Dilation

vmopen:
    Opening

vmclose:
    Closing

vmoredge:
    Edge extractor

vmskeleton:
    Skeleton extractor

These algorithms are obtained from:

    "Morphological Methods in Image and Signal Processing"

    Charles R. Giardina

    Edward R. Dougherty

    Prentice Hall, Englewood Cliffs, New Jersey 07632

ADVICE:

    The input image must be a morphological kernel (created by vmcustom).

SEE ALSO
vm180(1), intro(3), vipl(3), verror(3), vutils(3) vmcustom(1), lvmcustom(3).

RESTRICTIONS
vm180 works only on morphological kernels created by vmcustom, although, it can be used on normal images. In this case, remember that ispare1 and ispare2 will be modified.

AUTHOR
Pascal ADAM

COPYRIGHT
Copyright 1991, University of New Mexico. All rights reserved.