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/*
**
** Add gaussian, multiplicative gaussian, impulse, laplacian or
** poisson noise to a Netpbm image
**
** Version 1.0 November 1995
**
** Copyright (C) 1995 by Mike Burns (burns@cac.psu.edu)
**
** Adapted to Netpbm 2005.08.09, by Bryan Henderson
**
** Permission to use, copy, modify, and distribute this software and its
** documentation for any purpose and without fee is hereby granted, provided
** that the above copyright notice appear in all copies and that both that
** copyright notice and this permission notice appear in supporting
** documentation. This software is provided "as is" without express or
** implied warranty.
*/
/* 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
*/
#define _XOPEN_SOURCE 500 /* get M_PI in math.h */
#include <assert.h>
#include <math.h>
#include "pm_c_util.h"
#include "mallocvar.h"
#include "rand.h"
#include "shhopt.h"
#include "pm_gamma.h"
#include "pam.h"
static double const EPSILON = 1.0e-5;
static double const SALT_RATIO = 0.5;
static double
rand1(struct pm_randSt * const randStP) {
return (double)pm_rand(randStP)/RAND_MAX;
}
enum NoiseType {
NOISETYPE_GAUSSIAN,
NOISETYPE_IMPULSE, /* aka salt and pepper noise */
NOISETYPE_LAPLACIAN,
NOISETYPE_MULTIPLICATIVE_GAUSSIAN,
NOISETYPE_POISSON
};
struct CmdlineInfo {
/* All the information the user supplied in the command line,
in a form easy for the program to use.
*/
const char * inputFileName;
enum NoiseType noiseType;
unsigned int seedSpec;
unsigned int seed;
float lambda;
float lsigma;
float mgsigma;
float sigma1;
float sigma2;
float tolerance;
};
static enum NoiseType
typeFmName(const char * const name) {
enum NoiseType retval;
if (false)
assert(false);
else if (pm_keymatch(name, "gaussian", 1))
retval = NOISETYPE_GAUSSIAN;
else if (pm_keymatch(name, "impulse", 1))
retval = NOISETYPE_IMPULSE;
else if (pm_keymatch(name, "laplacian", 1))
retval = NOISETYPE_LAPLACIAN;
else if (pm_keymatch(name, "multiplicative_gaussian", 1))
retval = NOISETYPE_MULTIPLICATIVE_GAUSSIAN;
else if (pm_keymatch(name, "poisson", 1))
retval = NOISETYPE_POISSON;
else
pm_error("Unrecognized -type value '%s'. "
"We recognize 'gaussian', 'impulse', 'laplacian', "
"'multiplicative_gaussian', and 'poisson'", name);
return retval;
}
static void
parseCommandLine(int argc, const char ** const argv,
struct CmdlineInfo * const cmdlineP) {
/*----------------------------------------------------------------------------
Note that the file spec array we return is stored in the storage that
was passed to us as the argv array.
-----------------------------------------------------------------------------*/
optEntry * option_def;
/* Instructions to OptParseOptions3 on how to parse our options. */
optStruct3 opt;
unsigned int option_def_index;
unsigned int typeSpec, lambdaSpec, lsigmaSpec, mgsigmaSpec,
sigma1Spec, sigma2Spec, toleranceSpec;
const char * type;
MALLOCARRAY(option_def, 100);
option_def_index = 0; /* incremented by OPTENT3 */
OPTENT3(0, "type", OPT_STRING, &type,
&typeSpec, 0);
OPTENT3(0, "seed", OPT_UINT, &cmdlineP->seed,
&cmdlineP->seedSpec, 0);
OPTENT3(0, "lambda", OPT_FLOAT, &cmdlineP->lambda,
&lambdaSpec, 0);
OPTENT3(0, "lsigma", OPT_FLOAT, &cmdlineP->lsigma,
&lsigmaSpec, 0);
OPTENT3(0, "mgsigma", OPT_FLOAT, &cmdlineP->mgsigma,
&mgsigmaSpec, 0);
OPTENT3(0, "sigma1", OPT_FLOAT, &cmdlineP->sigma1,
&sigma1Spec, 0);
OPTENT3(0, "sigma2", OPT_FLOAT, &cmdlineP->sigma2,
&sigma2Spec, 0);
OPTENT3(0, "tolerance", OPT_FLOAT, &cmdlineP->tolerance,
&toleranceSpec, 0);
opt.opt_table = option_def;
opt.short_allowed = FALSE; /* We have no short (old-fashioned) options */
opt.allowNegNum = FALSE; /* We have no parms that are negative numbers */
pm_optParseOptions3(&argc, (char **)argv, opt, sizeof(opt), 0);
/* Uses and sets argc, argv, and some of *cmdlineP and others. */
if (!typeSpec)
cmdlineP->noiseType = NOISETYPE_GAUSSIAN;
else
cmdlineP->noiseType = typeFmName(type);
if (sigma1Spec && cmdlineP->noiseType != NOISETYPE_GAUSSIAN)
pm_error("-sigma1 is valid only with -type=gaussian");
if (sigma2Spec && cmdlineP->noiseType != NOISETYPE_GAUSSIAN)
pm_error("-sigma2 is valid only with -type=gaussian");
if (mgsigmaSpec &&
cmdlineP->noiseType != NOISETYPE_MULTIPLICATIVE_GAUSSIAN)
pm_error("-mgsigma is valid only with -type=multiplicative_guassian");
if (toleranceSpec && cmdlineP->noiseType != NOISETYPE_IMPULSE)
pm_error("-tolerance is valid only with -type=impulse");
if (lsigmaSpec && cmdlineP->noiseType != NOISETYPE_LAPLACIAN)
pm_error("-lsigma is valid only with -type=laplacian");
if (lambdaSpec && cmdlineP->noiseType != NOISETYPE_POISSON)
pm_error("-lambda is valid only with -type=poisson");
if (!lambdaSpec)
cmdlineP->lambda = 12.0;
if (!lsigmaSpec)
cmdlineP->lsigma = 10.0;
if (!mgsigmaSpec)
cmdlineP->mgsigma = 0.5;
if (!sigma1Spec)
cmdlineP->sigma1 = 4.0;
if (!sigma2Spec)
cmdlineP->sigma2 = 20.0;
if (!toleranceSpec)
cmdlineP->tolerance = 0.10;
if (!cmdlineP->seedSpec)
cmdlineP->seed = pm_randseed();
if (argc-1 > 1)
pm_error("Too many arguments (%u). File spec is the only argument.",
argc-1);
if (argc-1 < 1)
cmdlineP->inputFileName = "-";
else
cmdlineP->inputFileName = argv[1];
free(option_def);
}
static void
addGaussianNoise(sample const maxval,
sample const origSample,
sample * const newSampleP,
float const sigma1,
float const sigma2,
struct pm_randSt * const randStP) {
/*----------------------------------------------------------------------------
Add Gaussian noise.
Based on Kasturi/Algorithms of the ACM
-----------------------------------------------------------------------------*/
double x1, x2, xn, yn;
double rawNewSample;
x1 = rand1(randStP);
if (x1 == 0.0)
x1 = 1.0;
x2 = rand1(randStP);
xn = sqrt(-2.0 * log(x1)) * cos(2.0 * M_PI * x2);
yn = sqrt(-2.0 * log(x1)) * sin(2.0 * M_PI * x2);
rawNewSample =
origSample + (sqrt((double) origSample) * sigma1 * xn) + (sigma2 * yn);
*newSampleP = MAX(MIN((int)rawNewSample, maxval), 0);
}
static void
addImpulseNoise(sample const maxval,
sample const origSample,
sample * const newSampleP,
float const tolerance,
double const saltRatio,
struct pm_randSt * const randStP) {
/*----------------------------------------------------------------------------
Add impulse (salt and pepper) noise
-----------------------------------------------------------------------------*/
double const pepperRatio = 1.0 - saltRatio;
double const loTolerance = tolerance * pepperRatio;
double const hiTolerance = 1.0 - tolerance * saltRatio;
double const sap = rand1(randStP);
*newSampleP =
sap < loTolerance ? 0 :
sap >= hiTolerance? maxval :
origSample;
}
static void
addLaplacianNoise(sample const maxval,
double const infinity,
sample const origSample,
sample * const newSampleP,
float const lsigma,
struct pm_randSt * const randStP) {
/*----------------------------------------------------------------------------
Add Laplacian noise
From Pitas' book.
-----------------------------------------------------------------------------*/
double const u = rand1(randStP);
double rawNewSample;
if (u <= 0.5) {
if (u <= EPSILON)
rawNewSample = origSample - infinity;
else
rawNewSample = origSample + lsigma * log(2.0 * u);
} else {
double const u1 = 1.0 - u;
if (u1 <= 0.5 * EPSILON)
rawNewSample = origSample + infinity;
else
rawNewSample = origSample - lsigma * log(2.0 * u1);
}
*newSampleP = MIN(MAX((int)rawNewSample, 0), maxval);
}
static void
addMultiplicativeGaussianNoise(sample const maxval,
double const infinity,
sample const origSample,
sample * const newSampleP,
float const mgsigma,
struct pm_randSt * const randStP) {
/*----------------------------------------------------------------------------
Add multiplicative Gaussian noise
From Pitas' book.
-----------------------------------------------------------------------------*/
double rayleigh, gauss;
double rawNewSample;
{
double const uniform = rand1(randStP);
if (uniform <= EPSILON)
rayleigh = infinity;
else
rayleigh = sqrt(-2.0 * log( uniform));
}
{
double const uniform = rand1(randStP);
gauss = rayleigh * cos(2.0 * M_PI * uniform);
}
rawNewSample = origSample + (origSample * mgsigma * gauss);
*newSampleP = MIN(MAX((int)rawNewSample, 0), maxval);
}
static double
poissonPmf(double const lambda,
unsigned int const k) {
/*----------------------------------------------------------------------------
This is the probability mass function (PMF) of a discrete random variable
with lambda 'lambda'.
I.e. it gives the probability that a value sampled from a Poisson
distribution with lambda 'lambda' has the value 'k'.
That means it's the probability that in a Poisson stream of events in which
the mean number of events in an interval of a certains size is 'lambda' that
'k' events happen.
-----------------------------------------------------------------------------*/
double x;
unsigned int i;
/* We're computing the formula
(pow(lamda, k) * exp(-lambda)) / fact(k).
Note that k is ordinarily quite small.
*/
x = exp(-lambda);
for (i = 1; i <= k; ++i) {
x *= lambda;
x /= i;
}
return x;
}
static void
addPoissonNoise(struct pam * const pamP,
sample const origSample,
sample * const newSampleP,
float const lambdaOfMaxval,
struct pm_randSt * const randStP) {
/*----------------------------------------------------------------------------
Add Poisson noise
-----------------------------------------------------------------------------*/
samplen const origSamplen = pnm_normalized_sample(pamP, origSample);
float const origSampleIntensity = pm_ungamma709(origSamplen);
double const lambda = origSampleIntensity * lambdaOfMaxval;
double const u = rand1(randStP);
/* We now apply the inverse CDF (cumulative distribution function) of the
Poisson distribution to uniform random variable 'u' to get a Poisson
random variable. Unfortunately, we have no algebraic equation for the
inverse of the CDF, but the random variable is discrete, so we can just
iterate.
*/
unsigned int k;
double cumProb;
for (k = 0, cumProb = 0.0; k < lambdaOfMaxval; ++k) {
cumProb += poissonPmf(lambda, k);
if (cumProb >= u)
break;
}
{
samplen const newSamplen = pm_gamma709(k/lambdaOfMaxval);
*newSampleP = pnm_unnormalized_sample(pamP, newSamplen);
}
}
int
main(int argc, const char ** argv) {
FILE * ifP;
struct CmdlineInfo cmdline;
struct pam inpam;
struct pam outpam;
tuple * tuplerow;
const tuple * newtuplerow;
unsigned int row;
double infinity;
struct pm_randSt randSt;
pm_proginit(&argc, argv);
parseCommandLine(argc, argv, &cmdline);
pm_randinit(&randSt);
pm_srand2(&randSt, cmdline.seedSpec, cmdline.seed);
ifP = pm_openr(cmdline.inputFileName);
pnm_readpaminit(ifP, &inpam, PAM_STRUCT_SIZE(tuple_type));
outpam = inpam;
outpam.file = stdout;
pnm_writepaminit(&outpam);
tuplerow = pnm_allocpamrow(&inpam);
newtuplerow = pnm_allocpamrow(&inpam);
infinity = (double) inpam.maxval;
for (row = 0; row < inpam.height; ++row) {
unsigned int col;
pnm_readpamrow(&inpam, tuplerow);
for (col = 0; col < inpam.width; ++col) {
unsigned int plane;
for (plane = 0; plane < inpam.depth; ++plane) {
switch (cmdline.noiseType) {
case NOISETYPE_GAUSSIAN:
addGaussianNoise(inpam.maxval,
tuplerow[col][plane],
&newtuplerow[col][plane],
cmdline.sigma1, cmdline.sigma2,
&randSt);
break;
case NOISETYPE_IMPULSE:
addImpulseNoise(inpam.maxval,
tuplerow[col][plane],
&newtuplerow[col][plane],
cmdline.tolerance, SALT_RATIO,
&randSt);
break;
case NOISETYPE_LAPLACIAN:
addLaplacianNoise(inpam.maxval, infinity,
tuplerow[col][plane],
&newtuplerow[col][plane],
cmdline.lsigma,
&randSt);
break;
case NOISETYPE_MULTIPLICATIVE_GAUSSIAN:
addMultiplicativeGaussianNoise(inpam.maxval, infinity,
tuplerow[col][plane],
&newtuplerow[col][plane],
cmdline.mgsigma,
&randSt);
break;
case NOISETYPE_POISSON:
addPoissonNoise(&inpam,
tuplerow[col][plane],
&newtuplerow[col][plane],
cmdline.lambda,
&randSt);
break;
}
}
}
pnm_writepamrow(&outpam, newtuplerow);
}
pm_randterm(&randSt);
pnm_freepamrow(newtuplerow);
pnm_freepamrow(tuplerow);
return 0;
}
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