pnmaddnoise(1)pnmaddnoise(1)NAMEpnmaddnoise - add noise to a portable anymap
SYNOPSISpnmaddnoise [-type noise_type] [-seed int]
pnmaddnoise-type gaussian [-sigma1 value] [-sigma2 value]
[-seed int] [pnmfile]
pnmaddnoise-type multiplicative_gaussian [-msigma value]
[-seed int] [pnmfile]
pnmaddnoise-type impulse [-tolerence ratio] [-seed int]
[pnmfile]
pnmaddnoise-type laplacian [-lsigma value] [-seed int]
[pnmfile]
pnmaddnoise-type poisson [-lambda value] [-seed int]
[pnmfile]
DESCRIPTION
Adds the specified noise type to a portable anymap. PPM
files are treated one color plane at a time, not as a col-
orspace. See source code for meaning of options particu-
lar to each noise type.
OPTIONS-lambda value
Used for poisson noise only. The default value is
0.05.
-lsigma value
Used for laplacian noise only. The default value
is 10.0.
-msigma value
Used for mutliplicative gaussian noise only. The
default value is 0.5.
-seed int
Used for all noise types. Set the initial random
number generator seed value.
-sigma1 value
Used for gaussian noise only. The default value is
4.0.
-sigma2 value
Used for gaussian noise only. The default value is
20.0.
-tolerence ratio
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 MAXVAL.
-type noise_type
Select type of noise by name. The following noise
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pnmaddnoise(1)pnmaddnoise(1)
types are available: gaussian, multiplicative_gaus-
sian, impulse, laplacian, poisson. Only enough
letters to be unique are required for the noise
type option. The default noise type is gaussian.
BUGS
PPM files are treated one color plane at a time, not as a
color space.
REFERENCES
"Adaptive Image Restoration in Signal-Dependent Noise" by
R. Kasturi Institute for Electronic Science, Texas Tech
University, 1982
"Digital Image Processing Algorithms" by Ioannis Pitas,
Prentice Hall, 1993 ISBN 0-13-145814-0
SEE ALSOpgmnoise(1), pnm(5), pnmmedian(1), pnmsmooth(1)AUTHOR
Copyright (C) 1995 by Mike Burns <burns@cac.psu.edu>
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