NAME
minimum_filter - typically applied to an image to remove
positive outlier noise.
SYNOPSIS
#include <CVIPtoolk.h>
#include <CVIPdef.h>
#include <CVIPspfltr.h>
#include <float.h>
Image *minimum_filter(Image *imageP, int mask_size)
<imageP> - pointer to an Image structure.
<mask_size> - size of the filtering window (e.g., 3->
3x3).
PATH
$CVIPHOME/SPATIALFILTER/spatial_filter.c
OPTIONS
None.
DESCRIPTION
Returns the minimum value of the set of pixels contained in
the N x N filter window.
TIPS
Works best on images containing positive outlier noise. This
filter will darken the appearance of the image. Keep mask
size small to minimize blurring.
DIAGNOSTICS
Returns error message if invalid filter size is entered.
Size of filter is to be an odd integer limited from < 3 - 31
>.
EXAMPLE
#include <CVIPtoolkit.h>
#include <CVIPimage.h>
#include <CVIPdef.h>
#include <CVIPspfltr.h>
#include <CVIPconvert.h>
#include <CVIPview.h>
#define VIEWER "picture"
#define VIDEO_APP "SunVideo &"
void main()
{
Image *cvipImage;
IMAGE_FORMAT format;
char *inputfile,*outputfile;
setDisplay_Image(VIEWER, "Default");
print_CVIP("\n\t\tEnter the Input File Name: ");
inputfile =(char *) getString_CVIP();
format = getFormat_CVIP(inputfile);
cvipImage = read_Image(inputfile,1);
view_Image(cvipImage, inputfile);
free(inputfile);
/* the following call replaces each pixel value by the
minimum pixel value in a 3 x 3 window */
cvipImage = minimum_filter(cvipImage,3);
print_CVIP("\n\t\tEnter the Output File Name: ");
outputfile = getString_CVIP();
view_Image(cvipImage,outputfile);
write_Image(cvipImage,outputfile,CVIP_NO,CVIP_NO,format,1);
free(outputfile);
}
BUGS
None.
AUTHOR
Copyright (C) 1992, 1996 SIUE - by Scott E. Umbaugh and John
A Creighton.