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commit : Denoise Levels added

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Rafat Hussain 2017-08-11 16:21:33 +05:30
parent 72a3e5c580
commit 46ef7cb1b9
4 changed files with 280 additions and 281 deletions
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554
denoise/denoise.c
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@ -1,277 +1,277 @@
#include "denoise.h" #include "denoise.h"
int compare_double(const void* a, const void* b) int compare_double(const void* a, const void* b)
{ {
double arg1 = *(const double*)a; double arg1 = *(const double*)a;
double arg2 = *(const double*)b; double arg2 = *(const double*)b;
if (arg1 < arg2) return -1; if (arg1 < arg2) return -1;
if (arg1 > arg2) return 1; if (arg1 > arg2) return 1;
return 0; return 0;
} }
double median(double *x, int N) { double median(double *x, int N) {
double sigma; double sigma;
qsort(x, N, sizeof(double), compare_double); qsort(x, N, sizeof(double), compare_double);
if ((N % 2) == 0) { if ((N % 2) == 0) {
sigma = (x[N/2 - 1] + x[N/2] ) / 2.0; sigma = (x[N/2 - 1] + x[N/2] ) / 2.0;
} else { } else {
sigma = x[N/2]; sigma = x[N/2];
} }
return sigma; return sigma;
} }
double mad(double *x, int N) { double mad(double *x, int N) {
double sigma; double sigma;
int i; int i;
sigma = median(x,N); sigma = median(x,N);
for(i = 0; i < N;++i) { for(i = 0; i < N;++i) {
x[i] = (x[i] - sigma) > 0 ? (x[i] - sigma) : -(x[i] - sigma); x[i] = (x[i] - sigma) > 0 ? (x[i] - sigma) : -(x[i] - sigma);
} }
sigma = median(x,N); sigma = median(x,N);
return sigma; return sigma;
} }
int minindex(double *arr, int N) { int minindex(double *arr, int N) {
double min; double min;
int index,i; int index,i;
min = DBL_MAX; min = DBL_MAX;
index = 0; index = 0;
for(i = 0; i < N;++i) { for(i = 0; i < N;++i) {
if (arr[i] < min) { if (arr[i] < min) {
min = arr[i]; min = arr[i];
index = i; index = i;
} }
} }
return index; return index;
} }
void getDWTAppx(wt_object wt, double *appx,int N) { void getDWTAppx(wt_object wt, double *appx,int N) {
/* /*
Wavelet decomposition is stored as Wavelet decomposition is stored as
[A(J) D(J) D(J-1) ..... D(1)] in wt->output vector [A(J) D(J) D(J-1) ..... D(1)] in wt->output vector
Length of A(J) , N = wt->length[0] Length of A(J) , N = wt->length[0]
*/ */
int i; int i;
for (i = 0; i < N; ++i) { for (i = 0; i < N; ++i) {
appx[i] = wt->output[i]; appx[i] = wt->output[i];
} }
} }
void getDWTDetail(wt_object wt, double *detail, int N, int level) { void getDWTDetail(wt_object wt, double *detail, int N, int level) {
/* /*
returns Detail coefficents at the jth level where j = 1,2,.., J returns Detail coefficents at the jth level where j = 1,2,.., J
and Wavelet decomposition is stored as and Wavelet decomposition is stored as
[A(J) D(J) D(J-1) ..... D(1)] in wt->output vector [A(J) D(J) D(J-1) ..... D(1)] in wt->output vector
Use getDWTAppx() to get A(J) Use getDWTAppx() to get A(J)
Level 1 : Length of D(J), ie N, is stored in wt->length[1] Level 1 : Length of D(J), ie N, is stored in wt->length[1]
Level 2 :Length of D(J-1), ie N, is stored in wt->length[2] Level 2 :Length of D(J-1), ie N, is stored in wt->length[2]
.... ....
Level J : Length of D(1), ie N, is stored in wt->length[J] Level J : Length of D(1), ie N, is stored in wt->length[J]
*/ */
int i, iter, J; int i, iter, J;
J = wt->J; J = wt->J;
if (level > J) { if (level > J) {
printf("The decomposition only has %d levels", J); printf("The decomposition only has %d levels", J);
} }
iter = wt->length[0]; iter = wt->length[0];
for (i = 1; i < level; ++i) { for (i = 1; i < level; ++i) {
iter += wt->length[i]; iter += wt->length[i];
} }
for (i = 0; i < N; ++i) { for (i = 0; i < N; ++i) {
detail[i] = wt->output[i + iter]; detail[i] = wt->output[i + iter];
} }
} }
void visushrink(double *signal,int N,int J,char *wname,char *method,char *ext,char *thresh,double *denoised) { void visushrink(double *signal,int N,int J,char *wname,char *method,char *ext,char *thresh,double *denoised) {
int filt_len,iter,i,dlen,dwt_len,sgn, MaxIter; int filt_len,iter,i,dlen,dwt_len,sgn, MaxIter;
double sigma,td,tmp; double sigma,td,tmp;
wave_object wave; wave_object wave;
wt_object wt; wt_object wt;
double *dout; double *dout;
wave = wave_init(wname); wave = wave_init(wname);
filt_len = wave->filtlength; filt_len = wave->filtlength;
MaxIter = (int) (log((double)N / ((double)filt_len - 1.0)) / log(2.0)); MaxIter = (int) (log((double)N / ((double)filt_len - 1.0)) / log(2.0));
if (J > MaxIter) { if (J > MaxIter) {
printf("\n Error - The Signal Can only be iterated %d times using this wavelet. Exiting\n",MaxIter); printf("\n Error - The Signal Can only be iterated %d times using this wavelet. Exiting\n",MaxIter);
exit(-1); exit(-1);
} }
wt = wt_init(wave,method,N,J); wt = wt_init(wave,method,N,J);
setDWTExtension(wt,ext); setDWTExtension(wt,ext);
dwt(wt,signal); dwt(wt,signal);
//Set sigma //Set sigma
iter = wt->length[0]; iter = wt->length[0];
dlen = wt->length[J]; dlen = wt->length[J];
dout = (double*)malloc(sizeof(double) * dlen); dout = (double*)malloc(sizeof(double) * dlen);
for (i = 1; i < J; ++i) { for (i = 1; i < J; ++i) {
iter += wt->length[i]; iter += wt->length[i];
} }
for(i = 0; i < dlen;++i) { for(i = 0; i < dlen;++i) {
dout[i] = wt->output[iter+i]; dout[i] = wt->output[iter+i];
} }
sigma = mad(dout,dlen); sigma = mad(dout,dlen);
dwt_len = wt->outlength; dwt_len = wt->outlength;
td = sqrt(2.0 * log(dwt_len)) * sigma / 0.6745; td = sqrt(2.0 * log(dwt_len)) * sigma / 0.6745;
if(!strcmp(thresh,"hard")) { if(!strcmp(thresh,"hard")) {
for(i = 0; i < dwt_len;++i) { for(i = 0; i < dwt_len;++i) {
if (fabs(wt->output[i]) < td) { if (fabs(wt->output[i]) < td) {
wt->output[i] = 0; wt->output[i] = 0;
} }
} }
} else if(!strcmp(thresh,"soft")) { } else if(!strcmp(thresh,"soft")) {
for(i = 0; i < dwt_len;++i) { for(i = 0; i < dwt_len;++i) {
if (fabs(wt->output[i]) < td) { if (fabs(wt->output[i]) < td) {
wt->output[i] = 0; wt->output[i] = 0;
} else { } else {
sgn = wt->output[i] >= 0 ? 1 : -1; sgn = wt->output[i] >= 0 ? 1 : -1;
tmp = sgn * (fabs(wt->output[i]) - td); tmp = sgn * (fabs(wt->output[i]) - td);
wt->output[i] = tmp; wt->output[i] = tmp;
} }
} }
} }
idwt(wt,denoised); idwt(wt,denoised);
free(dout); free(dout);
wave_free(wave); wave_free(wave);
wt_free(wt); wt_free(wt);
} }
void sureshrink(double *signal,int N,int J,char *wname,char *method,char *ext,char *thresh,double *denoised) { void sureshrink(double *signal,int N,int J,char *wname,char *method,char *ext,char *thresh,double *denoised) {
int filt_len,i,it,len,dlen,dwt_len,min_index,sgn, MaxIter; int filt_len,i,it,len,dlen,dwt_len,min_index,sgn, MaxIter;
double sigma,norm,td,tv,te,ct,thr,temp,x_sum; double sigma,norm,td,tv,te,ct,thr,temp,x_sum;
wave_object wave; wave_object wave;
wt_object wt; wt_object wt;
double *dout,*risk; double *dout,*risk;
wave = wave_init(wname); wave = wave_init(wname);
filt_len = wave->filtlength; filt_len = wave->filtlength;
MaxIter = (int) (log((double)N / ((double)filt_len - 1.0)) / log(2.0)); MaxIter = (int) (log((double)N / ((double)filt_len - 1.0)) / log(2.0));
// Depends on J
if (J > MaxIter) { if (J > MaxIter) {
printf("\n Error - The Signal Can only be iterated %d times using this wavelet. Exiting\n",MaxIter); printf("\n Error - The Signal Can only be iterated %d times using this wavelet. Exiting\n",MaxIter);
exit(-1); exit(-1);
} }
wt = wt_init(wave,method,N,J); wt = wt_init(wave,method,N,J);
setDWTExtension(wt,ext); setDWTExtension(wt,ext);
dwt(wt,signal); dwt(wt,signal);
len = wt->length[0]; len = wt->length[0];
dlen = wt->length[J]; dlen = wt->length[J];
dout = (double*)malloc(sizeof(double) * dlen); dout = (double*)malloc(sizeof(double) * dlen);
risk = (double*)malloc(sizeof(double) * dlen); risk = (double*)malloc(sizeof(double) * dlen);
for(it = 0; it < J;++it) { for(it = 0; it < J;++it) {
dwt_len = wt->length[it+1]; dwt_len = wt->length[it+1];
for(i = 0; i < dlen;++i) { for(i = 0; i < dlen;++i) {
dout[i] = wt->output[len+i]; dout[i] = wt->output[len+i];
} }
sigma = mad(dout,dwt_len); sigma = mad(dout,dwt_len);
if ( sigma < 0.00000001) { if ( sigma < 0.00000001) {
td = 0; td = 0;
} else { } else {
tv = sqrt(2.0 * log(dwt_len)); tv = sqrt(2.0 * log(dwt_len));
norm = 0.0; norm = 0.0;
for(i = 0; i < dwt_len;++i) { for(i = 0; i < dwt_len;++i) {
norm += (wt->output[len+i] *wt->output[len+i]); norm += (wt->output[len+i] *wt->output[len+i]);
} }
te =(norm - (double) dwt_len)/(double) dwt_len; te =(norm - (double) dwt_len)/(double) dwt_len;
ct = pow(log((double) dwt_len)/log(2.0),1.5)/sqrt((double) dwt_len); ct = pow(log((double) dwt_len)/log(2.0),1.5)/sqrt((double) dwt_len);
if (te < ct) { if (te < ct) {
td = tv; td = tv;
} else { } else {
x_sum = 0.0; x_sum = 0.0;
for(i = 0; i < dlen;++i) { for(i = 0; i < dlen;++i) {
dout[i] = wt->output[len+i]; dout[i] = wt->output[len+i];
} }
qsort(dout, N, sizeof(double), compare_double); qsort(dout, N, sizeof(double), compare_double);
for(i = 0; i < dwt_len;++i) { for(i = 0; i < dwt_len;++i) {
dout[i] = (dout[i]*dout[i]); dout[i] = (dout[i]*dout[i]);
x_sum += dout[i]; x_sum += dout[i];
} }
for(i = 0;i < dwt_len;++i) { for(i = 0;i < dwt_len;++i) {
risk[i] = ((double)dwt_len + 1 - 2 * ((double)i + 1) +x_sum + risk[i] = ((double)dwt_len + 1 - 2 * ((double)i + 1) +x_sum +
dout[i]*((double)dwt_len - 1 -(double) i))/(double)dwt_len; dout[i]*((double)dwt_len - 1 -(double) i))/(double)dwt_len;
} }
min_index = minindex(risk,dwt_len); min_index = minindex(risk,dwt_len);
thr = sqrt(dout[min_index]); thr = sqrt(dout[min_index]);
td = thr < tv ? thr : tv; td = thr < tv ? thr : tv;
} }
} }
td = td * sigma / 0.6745; td = td * sigma / 0.6745;
if(!strcmp(thresh,"hard")) { if(!strcmp(thresh,"hard")) {
for(i = 0; i < dwt_len;++i) { for(i = 0; i < dwt_len;++i) {
if (fabs(wt->output[len+i]) < td) { if (fabs(wt->output[len+i]) < td) {
wt->output[len+i] = 0; wt->output[len+i] = 0;
} }
} }
} else if(!strcmp(thresh,"soft")) { } else if(!strcmp(thresh,"soft")) {
for(i = 0; i < dwt_len;++i) { for(i = 0; i < dwt_len;++i) {
if (fabs(wt->output[len + i]) < td) { if (fabs(wt->output[len + i]) < td) {
wt->output[len+i] = 0; wt->output[len+i] = 0;
} else { } else {
sgn = wt->output[len+i] >= 0 ? 1 : -1; sgn = wt->output[len+i] >= 0 ? 1 : -1;
temp = sgn * (fabs(wt->output[len+i]) - td); temp = sgn * (fabs(wt->output[len+i]) - td);
wt->output[len+i] = temp; wt->output[len+i] = temp;
} }
} }
} }
len += wt->length[it+1]; len += wt->length[it+1];
} }
idwt(wt,denoised); idwt(wt,denoised);
free(dout); free(dout);
free(risk); free(risk);
wave_free(wave); wave_free(wave);
wt_free(wt); wt_free(wt);
} }

2
denoise/denoise.h
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@ -15,7 +15,7 @@ Copyright (c) 2017, Rafat Hussain
extern "C" { extern "C" {
#endif #endif
//depends on J
void visushrink(double *signal,int N,int J,char *wname,char *method,char *ext,char *thresh,double *denoised); void visushrink(double *signal,int N,int J,char *wname,char *method,char *ext,char *thresh,double *denoised);
void sureshrink(double *signal,int N,int J,char *wname,char *method,char *ext,char *thresh,double *denoised); void sureshrink(double *signal,int N,int J,char *wname,char *method,char *ext,char *thresh,double *denoised);

3
header/denoise.h
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@ -10,13 +10,12 @@ Copyright (c) 2017, Rafat Hussain
extern "C" { extern "C" {
#endif #endif
//depends on J
void visushrink(double *signal,int N,int J,char *wname,char *method,char *ext,char *thresh,double *denoised); void visushrink(double *signal,int N,int J,char *wname,char *method,char *ext,char *thresh,double *denoised);
void sureshrink(double *signal,int N,int J,char *wname,char *method,char *ext,char *thresh,double *denoised); void sureshrink(double *signal,int N,int J,char *wname,char *method,char *ext,char *thresh,double *denoised);
void sureshrink(double *signal,int N,char *wname,char *method,char *ext,char *thresh,double *denoised);
double mad(double *x, int N); double mad(double *x, int N);

2
test/denoisetest.c
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@ -40,7 +40,7 @@ int main() {
} }
//visushrink(inp,N,wname,method,ext,thresh,oup); //visushrink(inp,N,wname,method,ext,thresh,oup);
sureshrink(inp,N,wname,method,ext,thresh,oup); sureshrink(inp,N,J,wname,method,ext,thresh,oup);
ofp = fopen("denoiseds.txt", "w"); ofp = fopen("denoiseds.txt", "w");