From 1017cbebe5d5edd859e0fddad0a8600f509f4821 Mon Sep 17 00:00:00 2001 From: giraffedata Date: Mon, 25 Dec 2006 03:06:05 +0000 Subject: Place user guide into Subversion repository git-svn-id: http://svn.code.sf.net/p/netpbm/code/userguide@181 9d0c8265-081b-0410-96cb-a4ca84ce46f8 --- pgmmedian.html | 135 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 135 insertions(+) create mode 100644 pgmmedian.html (limited to 'pgmmedian.html') diff --git a/pgmmedian.html b/pgmmedian.html new file mode 100644 index 00000000..8a2a1a1f --- /dev/null +++ b/pgmmedian.html @@ -0,0 +1,135 @@ + +Pgmmedian User Manual + +

pgmmedian

+Updated: 28 August 2005 +

+ +Table Of Contents + +

NAME

+ +pgmmedian - apply a median filter to a PGM file + +

SYNOPSIS

+ +pgmmedian + +[-width=n] + +[-height=n] + +[-type=median_type] + +[-cutoff=int] + +[pnmfile] + + +

Minimum unique abbreviation of option is acceptable. You may use double +hyphens instead of single hyphen to denote options. You may use white +space in place of the equals sign to separate an option name from its value. + +

DESCRIPTION

+ +

This program is part of Netpbm. + +

pgmmedian applies a median filter to a PGM image, using either +the histogram sort of select kth value method to determine the median. + +

See the -type and -cutoff options for information on +how pgmmedian chooses between the two methods. + +

OPTIONS

+ +
+
-cutoff int + +
This option provides the cutoff value that pgmmedian uses +to decide between using the histogram sort or select kth value method +to find the median. + +If (maxval / ((width * height) - 1)), where +maxval is the maxval of the image and width and +height are the dimensions of the mask, is less than the cutoff +value, pgmmedian uses histogram sort. Otherwise, it uses kth +value. + +

If expression is less than the cutoff, pgmmedian uses the +histogram sort. Otherwise it uses the select kth value method. + +

This option has no effect if you specify -type. + +

The default is 250 + +

-width=n + +
Width of the median mask to apply. + +

Default is 3. + +

-height=n + +
Height of the median mask to apply. + +

Default is 3. + +

-type median_type + +
This option selects which method to use to find median regardless +of cutoff value. Choices are histogram_sort and select. + +

By default, pgmmedian decides which method to use as described +under the -cutoff option. + +

+ +

REFERENCES

+ + + + +

SEE ALSO

+ +pgmnoise, +pamaddnoise, +pgm + +

HISTORY

+ +

pgmmedian was added to Netpbm in Version 10.29 (August 2005). +It had been distributed by Mike Burns via his own web site before that +(and continued to be so). + + +

AUTHOR

+ +Copyright (C) 1996 by Mike Burns <burns@cac.psu.edu> + +
+

Table Of Contents

+ + + + -- cgit 1.4.1