226 lines
8.6 KiB
C++

/*
* This file is part of RawTherapee.
*
* Copyright (c) 2004-2010 Gabor Horvath <hgabor@rawtherapee.com>
*
* RawTherapee is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* RawTherapee is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with RawTherapee. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef _GAUSS_H_
#define _GAUSS_H_
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <alignedbuffer.h>
#ifdef _OPENMP
#include <omp.h>
#endif
// classical filtering if the support window is small:
template<class T> void gaussHorizontal3 (T** src, T** dst, T* buffer, int W, int H, const float c0, const float c1, bool multiThread) {
#ifdef _OPENMP
#pragma omp for
#endif
for (int i=0; i<H; i++) {
T* temp = buffer;
for (int j=1; j<W-1; j++)
temp[j] = (T)(c1 * (src[i][j-1] + src[i][j+1]) + c0 * src[i][j]);
dst[i][0] = src[i][0];
memcpy (dst[i]+1, temp+1, (W-2)*sizeof(T));
dst[i][W-1] = src[i][W-1];
}
}
template<class T> void gaussVertical3 (T** src, T** dst, T* buffer, int W, int H, const float c0, const float c1, bool multiThread) {
//#pragma omp parallel for if (multiThread)
#ifdef _OPENMP
#pragma omp for
#endif
for (int i=0; i<W; i++) {
T* temp = buffer;
for (int j = 1; j<H-1; j++)
temp[j] = (T)(c1 * (src[j-1][i] + src[j+1][i]) + c0 * src[j][i]);
dst[0][i] = src[0][i];
for (int j=1; j<H-1; j++)
dst[j][i] = temp[j];
dst[H-1][i] = src[H-1][i];
}
}
// fast gaussian approximation if the support window is large
template<class T> void gaussHorizontal (T** src, T** dst, AlignedBuffer<double>* buffer, int W, int H, double sigma, bool multiThread) {
if (sigma<0.25) {
// dont perform filtering
if (src!=dst)
for (int i = 0; i<H; i++)
memcpy (dst[i], src[i], W*sizeof(T));
return;
}
if (sigma<0.6) {
// compute 3x3 kernel
double c1 = exp (-1.0 / (2.0 * sigma * sigma));
double csum = 2.0 * c1 + 1.0;
c1 /= csum;
double c0 = 1.0 / csum;
gaussHorizontal3<T> (src, dst, (T*)(buffer->data), W, H, c0, c1, multiThread);
return;
}
// coefficient calculation
double q = 0.98711 * sigma - 0.96330;
if (sigma<2.5)
q = 3.97156 - 4.14554 * sqrt (1.0 - 0.26891 * sigma);
double b0 = 1.57825 + 2.44413*q + 1.4281*q*q + 0.422205*q*q*q;
double b1 = 2.44413*q + 2.85619*q*q + 1.26661*q*q*q;
double b2 = -1.4281*q*q - 1.26661*q*q*q;
double b3 = 0.422205*q*q*q;
double B = 1.0 - (b1+b2+b3) / b0;
b1 /= b0;
b2 /= b0;
b3 /= b0;
// From: Bill Triggs, Michael Sdika: Boundary Conditions for Young-van Vliet Recursive Filtering
double M[3][3];
M[0][0] = -b3*b1+1.0-b3*b3-b2;
M[0][1] = (b3+b1)*(b2+b3*b1);
M[0][2] = b3*(b1+b3*b2);
M[1][0] = b1+b3*b2;
M[1][1] = -(b2-1.0)*(b2+b3*b1);
M[1][2] = -(b3*b1+b3*b3+b2-1.0)*b3;
M[2][0] = b3*b1+b2+b1*b1-b2*b2;
M[2][1] = b1*b2+b3*b2*b2-b1*b3*b3-b3*b3*b3-b3*b2+b3;
M[2][2] = b3*(b1+b3*b2);
for (int i=0; i<3; i++)
for (int j=0; j<3; j++)
M[i][j] /= (1.0+b1-b2+b3)*(1.0+b2+(b1-b3)*b3);
// if (multiThread)
#pragma omp for
for (int i=0; i<H; i++) {
double* temp2 = buffer->data;
temp2[0] = B * src[i][0] + b1*src[i][0] + b2*src[i][0] + b3*src[i][0];
temp2[1] = B * src[i][1] + b1*temp2[0] + b2*src[i][0] + b3*src[i][0];
temp2[2] = B * src[i][2] + b1*temp2[1] + b2*temp2[0] + b3*src[i][0];
for (int j=3; j<W; j++)
temp2[j] = B * src[i][j] + b1*temp2[j-1] + b2*temp2[j-2] + b3*temp2[j-3];
double temp2Wm1 = src[i][W-1] + M[0][0]*(temp2[W-1] - src[i][W-1]) + M[0][1]*(temp2[W-2] - src[i][W-1]) + M[0][2]*(temp2[W-3] - src[i][W-1]);
double temp2W = src[i][W-1] + M[1][0]*(temp2[W-1] - src[i][W-1]) + M[1][1]*(temp2[W-2] - src[i][W-1]) + M[1][2]*(temp2[W-3] - src[i][W-1]);
double temp2Wp1 = src[i][W-1] + M[2][0]*(temp2[W-1] - src[i][W-1]) + M[2][1]*(temp2[W-2] - src[i][W-1]) + M[2][2]*(temp2[W-3] - src[i][W-1]);
temp2[W-1] = temp2Wm1;
temp2[W-2] = B * temp2[W-2] + b1*temp2[W-1] + b2*temp2W + b3*temp2Wp1;
temp2[W-3] = B * temp2[W-3] + b1*temp2[W-2] + b2*temp2[W-1] + b3*temp2W;
for (int j=W-4; j>=0; j--)
temp2[j] = B * temp2[j] + b1*temp2[j+1] + b2*temp2[j+2] + b3*temp2[j+3];
for (int j=0; j<W; j++)
dst[i][j] = (T)temp2[j];
}
}
template<class T> void gaussVertical (T** src, T** dst, AlignedBuffer<double>* buffer, int W, int H, double sigma, bool multiThread) {
if (sigma<0.25) {
// dont perform filtering
if (src!=dst)
for (int i = 0; i<H; i++)
memcpy (dst[i], src[i], W*sizeof(T));
return;
}
if (sigma<0.6) {
// compute 3x3 kernel
double c1 = exp (-1.0 / (2.0 * sigma * sigma));
double csum = 2.0 * c1 + 1.0;
c1 /= csum;
double c0 = 1.0 / csum;
gaussVertical3<T> (src, dst, (T*)(buffer->data), W, H, c0, c1, multiThread);
return;
}
// coefficient calculation
double q = 0.98711 * sigma - 0.96330;
if (sigma<2.5)
q = 3.97156 - 4.14554 * sqrt (1.0 - 0.26891 * sigma);
double b0 = 1.57825 + 2.44413*q + 1.4281*q*q + 0.422205*q*q*q;
double b1 = 2.44413*q + 2.85619*q*q + 1.26661*q*q*q;
double b2 = -1.4281*q*q - 1.26661*q*q*q;
double b3 = 0.422205*q*q*q;
double B = 1.0 - (b1+b2+b3) / b0;
b1 /= b0;
b2 /= b0;
b3 /= b0;
// From: Bill Triggs, Michael Sdika: Boundary Conditions for Young-van Vliet Recursive Filtering
double M[3][3];
M[0][0] = -b3*b1+1.0-b3*b3-b2;
M[0][1] = (b3+b1)*(b2+b3*b1);
M[0][2] = b3*(b1+b3*b2);
M[1][0] = b1+b3*b2;
M[1][1] = -(b2-1.0)*(b2+b3*b1);
M[1][2] = -(b3*b1+b3*b3+b2-1.0)*b3;
M[2][0] = b3*b1+b2+b1*b1-b2*b2;
M[2][1] = b1*b2+b3*b2*b2-b1*b3*b3-b3*b3*b3-b3*b2+b3;
M[2][2] = b3*(b1+b3*b2);
for (int i=0; i<3; i++)
for (int j=0; j<3; j++)
M[i][j] /= (1.0+b1-b2+b3)*(1.0+b2+(b1-b3)*b3);
#ifdef _OPENMP
#pragma omp for
#endif
for (int i=0; i<W; i++) {
double* temp2 = buffer->data;
temp2[0] = B * src[0][i] + b1*src[0][i] + b2*src[0][i] + b3*src[0][i];
temp2[1] = B * src[1][i] + b1*temp2[0] + b2*src[0][i] + b3*src[0][i];
temp2[2] = B * src[2][i] + b1*temp2[1] + b2*temp2[0] + b3*src[0][i];
for (int j=3; j<H; j++)
temp2[j] = B * src[j][i] + b1*temp2[j-1] + b2*temp2[j-2] + b3*temp2[j-3];
double temp2Hm1 = src[H-1][i] + M[0][0]*(temp2[H-1] - src[H-1][i]) + M[0][1]*(temp2[H-2] - src[H-1][i]) + M[0][2]*(temp2[H-3] - src[H-1][i]);
double temp2H = src[H-1][i] + M[1][0]*(temp2[H-1] - src[H-1][i]) + M[1][1]*(temp2[H-2] - src[H-1][i]) + M[1][2]*(temp2[H-3] - src[H-1][i]);
double temp2Hp1 = src[H-1][i] + M[2][0]*(temp2[H-1] - src[H-1][i]) + M[2][1]*(temp2[H-2] - src[H-1][i]) + M[2][2]*(temp2[H-3] - src[H-1][i]);
temp2[H-1] = temp2Hm1;
temp2[H-2] = B * temp2[H-2] + b1*temp2[H-1] + b2*temp2H + b3*temp2Hp1;
temp2[H-3] = B * temp2[H-3] + b1*temp2[H-2] + b2*temp2[H-1] + b3*temp2H;
for (int j=H-4; j>=0; j--)
temp2[j] = B * temp2[j] + b1*temp2[j+1] + b2*temp2[j+2] + b3*temp2[j+3];
for (int j=0; j<H; j++)
dst[j][i] = (T)temp2[j];
}
}
/*
void gaussHorizontal_unsigned (unsigned short** src, unsigned short** dst, AlignedBuffer<double>* buffer, int W, int row_from, int row_to, double sigma);
void gaussVertical_unsigned (unsigned short** src, unsigned short** dst, AlignedBuffer<double>* buffer, int H, int col_from, int col_to, double sigma);
void gaussHorizontal_signed (short** src, short** dst, AlignedBuffer<double>* buffer, int W, int row_from, int row_to, double sigma);
void gaussVertical_signed (short** src, short** dst, AlignedBuffer<double>* buffer, int H, int col_from, int col_to, double sigma);
void gaussHorizontal_float (float** src, float** dst, AlignedBuffer<double>* buffer, int W, int row_from, int row_to, double sigma);
void gaussVertical_float (float** src, float** dst, AlignedBuffer<double>* buffer, int H, int col_from, int col_to, double sigma);
*/
#endif