\
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.TH "Pamaddnoise User Manual" 0 "12 December 2020" "netpbm documentation"

.SH NAME

pamaddnoise - add noise to a Netpbm image

.UN synopsis
.SH SYNOPSIS

\fBpamaddnoise\fP
{
[\fB-type\fP \fBgaussian\fP]

[\fB-sigma1\fP \fIvalue\fP]

[\fB-sigma2\fP \fIvalue\fP]
|
\fB-type \fP \fBmultiplicative_gaussian\fP

[\fB-mgsigma\fP \fIvalue\fP]
|
\fB-type\fP \fBimpulse\fP

[\fB-tolerance\fP \fIratio\fP]
|
\fB-type \fP \fBlaplacian\fP

[\fB-lsigma\fP \fIvalue\fP]
|
\fB-type \fP \fBpoisson\fP

[\fB-lambda\fP \fIvalue\fP]
}
[\fB-seed\fP \fIint\fP]

[\fInetpbmfile\fP]

.UN description
.SH DESCRIPTION
.PP
This program is part of
.BR "Netpbm" (1)\c
\&.
.PP
\fBpamaddnoise\fP adds the specified noise type to a Netpbm image.
\fBpamaddnoise\fP treats a PPM image as 3 independent planes, not as
a plane of colors in a color space.

.UN options
.SH OPTIONS
.PP
In addition to the options common to all programs based on libnetpbm
(most notably \fB-quiet\fP, see 
.UR index.html#commonoptions
 Common Options
.UE
\&), \fBpamaddnoise\fP recognizes the following
command line options:


.TP
\fB-lambda\fP \fIvalue\fP
This is the expected value of the Poisson distribution for a sample value
  of mximum intensity.  The expected value for other intensities is
  proportional; e.g. for half intensity, it is half this value.
.sp
This is meaningful only with \fB-type=poisson\fP.
.sp
The default value is 12.

.TP
\fB-lsigma\fP \fIvalue\fP
Used for laplacian noise only.  The default value is 10.0.

.TP
\fB-mgsigma\fP \fIvalue\fP
Used for multiplicative gaussian noise only.  The default value is
0.5.

.TP
\fB-seed\fP \fIint\fP
Used for all noise types.  Set the initial random number generator
seed value.

.TP
\fB-sigma1\fP \fIvalue\fP
Used for gaussian noise only.  The default value is 4.0.

.TP
\fB-sigma2\fP \fIvalue\fP
Used for gaussian noise only.  The default value is 20.0.

.TP
\fB-tolerance\fP \fIratio\fP
Used for impulse noise only.  The default value is 0.10.  This means
that 5% of all pixel values will be set to 0 and 5% will be set to
the maxval

.TP
\fB-type\fP \fInoise_type\fP
Select type of noise by name.  The following noise types are
available: gaussian, multiplicative_gaussian, impulse, laplacian,
poisson.  Only enough letters to be unique are required for the noise
type option.  The default noise type is \fBgaussian\fP.


.IP \(bu
\fBgaussian\fP
.IP \(bu
\fBmultiplicative_gaussian\fP
.IP \(bu
\fBimpulse\fP
.IP \(bu
\fBlaplacian\fP
.IP \(bu
\fBpoisson\fP




.UN references
.SH REFERENCES


.IP \(bu
"Adaptive Image Restoration in Signal-Dependent Noise"
by R. Kasturi Institute for Electronic Science, Texas Tech University,
1982

.IP \(bu
"Digital Image Processing Algorithms" by Ioannis Pitas,
Prentice Hall, 1993 ISBN 0-13-145814-0



.UN seealso
.SH SEE ALSO
.BR "pgmnoise" (1)\c
\&,
.BR "pgmmedian" (1)\c
\&,
.BR "pnm" (1)\c
\&,
.BR "pam" (1)\c
\&,

.UN history
.SH HISTORY
.PP
\fBpamaddnoise\fP 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).
.PP
Burns' version, and the one in Netpbm 10.29, was called \fBpnmaddnoise\fP
and worked only on PNM images.  In Netpbm 10.30, it was converted to handle
PAM images and renamed to \fBpamaddnoise\fP.

.UN author
.SH AUTHOR

Copyright (C) 1995 by Mike Burns <\fIburns@cac.psu.edu\fP>
.SH DOCUMENT SOURCE
This manual page was generated by the Netpbm tool 'makeman' from HTML
source.  The master documentation is at
.IP
.B http://netpbm.sourceforge.net/doc/pamaddnoise.html
.PP