rawTherapee/rtengine/curves.cc

706 lines
22 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/>.
*/
#include <glib.h>
#include <glib/gstdio.h>
#include "curves.h"
#include <cmath>
#include <vector>
#include "mytime.h"
#include <cstring>
#include "array2D.h"
#include "LUT.h"
#undef CLIPD
#define CLIPD(a) ((a)>0.0f?((a)<1.0f?(a):1.0f):0.0f)
#define CLIP(a) ((a)<65535 ? (a) : (65535))
namespace rtengine {
Curve::Curve () {
x = 0;
y = 0;
ypp = 0;
hash = NULL;
hashSize = 1000; // has to be initiallised to the maximum value
}
Curve::~Curve () {
if (hash)
delete [] hash;
}
void Curve::AddPolygons ()
{
if (firstPointIncluded) {
poly_x.push_back(x1);
poly_y.push_back(y1);
}
for (int k=1; k<(nbr_points-1); k++) {
double t = k*increment;
double t2 = t*t;
double tr = 1.-t;
double tr2 = tr*tr;
double tr2t = tr*2*t;
// adding a point to the polyline
poly_x.push_back( tr2*x1 + tr2t*x2 + t2*x3);
poly_y.push_back( tr2*y1 + tr2t*y2 + t2*y3);
}
// adding the last point of the sub-curve
poly_x.push_back(x3);
poly_y.push_back(y3);
}
void Curve::fillHash() {
hash = new unsigned short int[hashSize+2];
unsigned int polyIter = 0;
double const increment = 1./hashSize;
double milestone = 0.;
for (unsigned int i=0; i<(hashSize+1);) {
while(poly_x[polyIter] <= milestone) ++polyIter;
hash[i] = polyIter-1;
milestone = (++i)*increment;
}
hash[hashSize+1] = poly_x.size()-1;
/*
// Debug output to file
FILE* f = fopen ("hash.txt", "wt");
for (int i=0; i<(hashSize+2); i++)
fprintf (f, "%d: %d > %.6f, %.6f\n", i, hash[i], poly_x[hash[i]], poly_y[hash[i]]);
fprintf (f, "\nppn: %d\npoly_x: %d\n", ppn, poly_x.size());
fclose (f);
*/
}
// Wikipedia sRGB: Unlike most other RGB color spaces, the sRGB gamma cannot be expressed as a single numerical value.
// The overall gamma is approximately 2.2, consisting of a linear (gamma 1.0) section near black, and a non-linear section elsewhere involving a 2.4 exponent
// and a gamma (slope of log output versus log input) changing from 1.0 through about 2.3.
const double CurveFactory::sRGBGamma = 2.2;
const double CurveFactory::sRGBGammaCurve = 2.4;
void fillCurveArray(DiagonalCurve* diagCurve, LUTf &outCurve, int skip, bool needed) {
if (needed) {
LUTf lutCurve (65536);
for (int i=0; i<=0xffff; i+= i<0xffff-skip ? skip : 1 ) {
// change to [0,1] range
double val = (double)i / 65535.0;
// apply custom/parametric/NURBS curve, if any
val = diagCurve->getVal (val);
// store result in a temporary array
lutCurve[i] = (val);
}
// if skip>1, let apply linear interpolation in the skipped points of the curve
if (skip > 1) {
int prev = 0;
for (int i=1; i<=0xffff-skip; i++) {
if (i%skip==0) {
prev+=skip;
continue;
}
lutCurve[i] = ( lutCurve[prev] * (skip - i%skip) + lutCurve[prev+skip] * (i%skip) ) / skip;
}
}
for (int i=0; i<=0xffff; i++) {
outCurve[i] = (65535.0 * lutCurve[i]);
}
}
else {
for (int i=0; i<=0xffff; i++) {
outCurve[i] = (float)i;
}
}
}
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
void CurveFactory::complexsgnCurve (double saturation, bool satlimit, double satlimthresh,
const std::vector<double>& acurvePoints, const std::vector<double>& bcurvePoints,
LUTf & aoutCurve, LUTf & boutCurve, LUTf & satCurve, int skip) {
//colormult = chroma_scale for Lab manipulations
//-----------------------------------------------------
bool needed;
DiagonalCurve* dCurve = NULL;
// check if contrast curve is needed
needed = (saturation<-0.0001 || saturation>0.0001);
// Filling the curve if needed
if (needed) {
//%%%%%%%%%%%%%%%%% Saturation curve's control points %%%%%%%%%%%%%%%%%
std::vector<double> satcurvePoints;
satcurvePoints.push_back((double)DCT_NURBS);
if (saturation>0) {
double satslope = (0.5+2*saturation/500.0)/(0.5-2*saturation/500.0);
double scale = (satlimthresh/100.1);
if (!satlimit) scale=100/100.1;
satcurvePoints.push_back(0); //black point. Value in [0 ; 1] range
satcurvePoints.push_back(0); //black point. Value in [0 ; 1] range
//if (satlimit) {
satcurvePoints.push_back(0.5-0.5*scale); //toe point
satcurvePoints.push_back(0.5-0.5*scale); //value at toe point
satcurvePoints.push_back(0.5-(0.5/satslope)*scale); //toe point
satcurvePoints.push_back(0.5-0.5*scale); //value at toe point
satcurvePoints.push_back(0.5+(0.5/satslope)*scale); //shoulder point
satcurvePoints.push_back(0.5+0.5*scale); //value at shoulder point
satcurvePoints.push_back(0.5+0.5*scale); //shoulder point
satcurvePoints.push_back(0.5+0.5*scale); //value at shoulder point
/*} else {
satcurvePoints.push_back(0.25+saturation/500.0); //toe point
satcurvePoints.push_back(0.25-saturation/500.0); //value at toe point
satcurvePoints.push_back(0.75-saturation/500.0); //shoulder point
satcurvePoints.push_back(0.75+saturation/500.0); //value at shoulder point
}*/
satcurvePoints.push_back(1); // white point
satcurvePoints.push_back(1); // value at white point
} else {
satcurvePoints.push_back(0);
satcurvePoints.push_back(-(saturation/200.0));
satcurvePoints.push_back(1);
satcurvePoints.push_back(1+saturation/200.0);
}
dCurve = new DiagonalCurve (satcurvePoints, CURVES_MIN_POLY_POINTS/skip);
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
fillCurveArray(dCurve, satCurve, skip, needed);
delete dCurve;
dCurve = NULL;
}
else {
fillCurveArray(NULL, satCurve, skip, needed);
}
//-----------------------------------------------------
needed = false;
// create a curve if needed
if (acurvePoints.size()>0 && acurvePoints[0]!=0) {
dCurve = new DiagonalCurve (acurvePoints, CURVES_MIN_POLY_POINTS/skip);
if (dCurve && !dCurve->isIdentity())
needed = true;
}
fillCurveArray(dCurve, aoutCurve, skip, needed);
if (dCurve) {
delete dCurve;
dCurve = NULL;
}
//-----------------------------------------------------
needed = false;
if (bcurvePoints.size()>0 && bcurvePoints[0]!=0) {
dCurve = new DiagonalCurve (bcurvePoints, CURVES_MIN_POLY_POINTS/skip);
if (dCurve && !dCurve->isIdentity())
needed = true;
}
fillCurveArray(dCurve, boutCurve, skip, needed);
if (dCurve) {
delete dCurve;
dCurve = NULL;
}
}
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
void CurveFactory::complexCurve (double ecomp, double black, double hlcompr, double hlcomprthresh,
double shcompr, double br, double contr, double gamma_, bool igamma_,
const std::vector<double>& curvePoints, LUTu & histogram, LUTu & histogramCropped,
LUTf & hlCurve, LUTf & shCurve, LUTf & outCurve,
LUTu & outBeforeCCurveHistogram, int skip) {
//double def_mul = pow (2.0, defmul);
/*printf ("def_mul= %f ecomp= %f black= %f hlcompr= %f shcompr= %f br= %f contr= %f defmul= %f
gamma= %f, skip= %d \n",def_mul,ecomp,black,hlcompr,shcompr,br,contr,defmul,gamma_,skip);*/
// compute parameters of the gamma curve
/*double start = exp(gamma_*log( -0.099 / ((1.0/gamma_-1.0)*1.099 )));
double slope = 1.099 * pow (start, 1.0/gamma_-1) - 0.099/start;
double mul = 1.099;
double add = 0.099;
// gamma BT709*/
//normalize gamma to sRGB
double start = exp(gamma_*log( -0.055 / ((1.0/gamma_-1.0)*1.055 )));
double slope = 1.055 * pow (start, 1.0/gamma_-1) - 0.055/start;
double mul = 1.055;
double add = 0.055;
// a: slope of the curve, black: starting point at the x axis
double a = pow (2.0, ecomp);
// curve without contrast
LUTf dcurve(0x10000);
// check if inverse gamma is needed at the end
bool needigamma = igamma_ && gamma_>0;
// clear array that stores histogram valid before applying the custom curve
outBeforeCCurveHistogram.clear();
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
// tone curve base. a: slope (from exp.comp.), b: black, def_mul: max. x value (can be>1), hr,sr: highlight,shadow recovery
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
DiagonalCurve* brightcurve = NULL;
// check if brightness curve is needed
if (br>0.00001 || br<-0.00001) {
std::vector<double> brightcurvePoints;
brightcurvePoints.push_back((double)DCT_NURBS);
brightcurvePoints.push_back(0.); //black point. Value in [0 ; 1] range
brightcurvePoints.push_back(0.); //black point. Value in [0 ; 1] range
if(br>0) {
brightcurvePoints.push_back(0.1); //toe point
brightcurvePoints.push_back(0.1+br/150.0); //value at toe point
brightcurvePoints.push_back(0.7); //shoulder point
brightcurvePoints.push_back(MIN(1.0,0.7+br/300.0)); //value at shoulder point
} else {
brightcurvePoints.push_back(MAX(0.0,0.1-br/150.0)); //toe point
brightcurvePoints.push_back(0.1); //value at toe point
brightcurvePoints.push_back(0.7-br/300.0); //shoulder point
brightcurvePoints.push_back(0.7); //value at shoulder point
}
brightcurvePoints.push_back(1.); // white point
brightcurvePoints.push_back(1.); // value at white point
brightcurve = new DiagonalCurve (brightcurvePoints, CURVES_MIN_POLY_POINTS/skip);
}
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
float exp_scale = a;
float scale = 65536.0;
float comp = (MAX(0,ecomp) + 1.0)*hlcompr/100.0;
float shoulder = ((scale/MAX(1,exp_scale))*(hlcomprthresh/200.0))+0.1;
//printf("shoulder = %e\n",shoulder);
//printf ("exp_scale= %f comp= %f def_mul=%f a= %f \n",exp_scale,comp,def_mul,a);
for (int i=0; i<0x10000; i++) {
// change to [0,1] range
float val = (float)i-shoulder;
if (comp>0.0)
{
if (val>0.0) {
float R = val*comp/(scale-shoulder);
hlCurve[i] = log(1.0+R*exp_scale)/R;
} else {
hlCurve[i]=exp_scale;
}
} else {
hlCurve[i]=exp_scale;
}
//%%%%%%%%%%%%%%%%%%%%%%%%%%
// change to [0,1] range
if (i!=0) {
val = (float)i / 65535.0f;
} else {
val = 1.0/65535.0;
}
float val2 = basecurve (val, 1.0, black, 1.0, 0.0, 1.5*shcompr/100.0);
shCurve[i] = CLIPD(val2)/val;
//%%%%%%%%%%%%%%%%%%%%%%%%%%
// change to [0,1] range
val = (double)i / 65535.0;
// gamma correction
if (gamma_>1)
val = gamma (val, gamma_, start, slope, mul, add);
// apply brightness curve
if (brightcurve)
val = brightcurve->getVal (val); // TODO: getVal(double) is very slow! Optimize with a LUTf
// store result in a temporary array
dcurve[i] = CLIPD(val);
}
if (brightcurve)
delete brightcurve;
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
// check if contrast curve is needed
if (contr>0.00001 || contr<-0.00001) {
// compute mean luminance of the image with the curve applied
int sum = 0;
float avg = 0;
//double sqavg = 0;
for (int i=0; i<=0xffff; i++) {
float fi=i;
fi = hlCurve[fi]*fi;
avg += dcurve[(int)(shCurve[fi]*fi)] * histogram[i];
//sqavg += dcurve[i]*dcurve[i] * histogram[i];
sum += histogram[i];
}
avg /= sum;
//sqavg /= sum;
//double stddev = sqrt(sqavg-avg*avg);
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
std::vector<double> contrastcurvePoints;
contrastcurvePoints.push_back((double)DCT_NURBS);
contrastcurvePoints.push_back(0); //black point. Value in [0 ; 1] range
contrastcurvePoints.push_back(0); //black point. Value in [0 ; 1] range
contrastcurvePoints.push_back(avg-avg*(0.6-contr/250.0)); //toe point
contrastcurvePoints.push_back(avg-avg*(0.6+contr/250.0)); //value at toe point
contrastcurvePoints.push_back(avg+(1-avg)*(0.6-contr/250.0)); //shoulder point
contrastcurvePoints.push_back(avg+(1-avg)*(0.6+contr/250.0)); //value at shoulder point
contrastcurvePoints.push_back(1); // white point
contrastcurvePoints.push_back(1); // value at white point
DiagonalCurve* contrastcurve = new DiagonalCurve (contrastcurvePoints, CURVES_MIN_POLY_POINTS/skip);
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
// apply contrast enhancement
for (int i=0; i<=0xffff; i++) {
dcurve[i] = contrastcurve->getVal (dcurve[i]);
}
delete contrastcurve;
}
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
// create a curve if needed
bool histNeeded = false;
DiagonalCurve* tcurve = NULL;
if (curvePoints.size()>0 && curvePoints[0]!=0) {
tcurve = new DiagonalCurve (curvePoints, CURVES_MIN_POLY_POINTS/skip);
if (outBeforeCCurveHistogram /*&& histogramCropped*/)
histNeeded = true;
}
if (tcurve && tcurve->isIdentity()) {
delete tcurve;
tcurve = NULL;
}
for (int i=0; i<=0xffff; i++) {
float val;
if (histNeeded) {
float fi=i;
float hval = hlCurve[i]*fi;
hval = dcurve[shCurve[hval]*hval];
//if (needigamma)
// hval = igamma2 (hval);
int hi = (int)(255.0*(hval));
outBeforeCCurveHistogram[hi] += histogram/*Cropped*/[i] ;
}
// apply custom/parametric/NURBS curve, if any
if (tcurve) {
val = tcurve->getVal (dcurve[i]); // TODO: getVal(double) is very slow! Optimize with a LUTf
} else {
val = (dcurve[i]);
}
// if inverse gamma is needed, do it (standard sRGB inverse gamma is applied)
if (needigamma)
val = igamma (val, gamma_, start, slope, mul, add);
outCurve[i] = (65535.0 * val);
}
if (tcurve)
delete tcurve;
/*if (outBeforeCCurveHistogram) {
for (int i=0; i<256; i++) printf("i= %d bchist= %d \n",i,outBeforeCCurveHistogram[i]);
}*/
}
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
void CurveFactory::complexLCurve (double br, double contr, const std::vector<double>& curvePoints,
LUTu & histogram, LUTu & histogramCropped, LUTf & outCurve,
LUTu & outBeforeCCurveHistogram, int skip) {
// curve without contrast
LUTf dcurve(65536,0);
// clear array that stores histogram valid before applying the custom curve
if (outBeforeCCurveHistogram)
outBeforeCCurveHistogram.clear();
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
// tone curve base. a: slope (from exp.comp.), b: black, def_mul: max. x value (can be>1), hr,sr: highlight,shadow recovery
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
// check if brightness curve is needed
if (br>0.00001 || br<-0.00001) {
std::vector<double> brightcurvePoints;
brightcurvePoints.push_back((double)((CurveType)DCT_NURBS));
brightcurvePoints.push_back(0.); // black point. Value in [0 ; 1] range
brightcurvePoints.push_back(0.); // black point. Value in [0 ; 1] range
if (br>0) {
brightcurvePoints.push_back(0.1); // toe point
brightcurvePoints.push_back(0.1+br/150.0); //value at toe point
brightcurvePoints.push_back(0.7); // shoulder point
brightcurvePoints.push_back(MIN(1.0,0.7+br/300.0)); //value at shoulder point
} else {
brightcurvePoints.push_back(0.1-br/150.0); // toe point
brightcurvePoints.push_back(0.1); // value at toe point
brightcurvePoints.push_back(MIN(1.0,0.7-br/300.0)); // shoulder point
brightcurvePoints.push_back(0.7); // value at shoulder point
}
brightcurvePoints.push_back(1.); // white point
brightcurvePoints.push_back(1.); // value at white point
DiagonalCurve* brightcurve = new DiagonalCurve (brightcurvePoints, CURVES_MIN_POLY_POINTS/skip);
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
// Applying brightness curve
for (int i=0; i<32768; i++) { // L values range up to 32767, higher values are for highlight overflow
// change to [0,1] range
float val = (float)i / 32767.0;
// apply brightness curve
val = brightcurve->getVal (val);
// store result in a temporary array
dcurve[i] = CLIPD(val);
}
delete brightcurve;
}
else {
for (int i=0; i<32768; i++) { // L values range up to 32767, higher values are for highlight overflow
// set the identity curve in the temporary array
dcurve[i] = (float)i / 32767.0;
}
}
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
// check if contrast curve is needed
if (contr>0.00001 || contr<-0.00001) {
// compute mean luminance of the image with the curve applied
int sum = 0;
float avg = 0;
//float sqavg = 0;
for (int i=0; i<32768; i++) {
avg += dcurve[i] * histogram[i];
//sqavg += dcurve[i]*dcurve[i] * histogram[i];
sum += histogram[i];
}
avg /= sum;
//sqavg /= sum;
//float stddev = sqrt(sqavg-avg*avg);
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
std::vector<double> contrastcurvePoints;
contrastcurvePoints.push_back((double)((CurveType)DCT_NURBS));
contrastcurvePoints.push_back(0.); // black point. Value in [0 ; 1] range
contrastcurvePoints.push_back(0.); // black point. Value in [0 ; 1] range
contrastcurvePoints.push_back(avg-avg*(0.6-contr/250.0)); // toe point
contrastcurvePoints.push_back(avg-avg*(0.6+contr/250.0)); // value at toe point
contrastcurvePoints.push_back(avg+(1-avg)*(0.6-contr/250.0)); // shoulder point
contrastcurvePoints.push_back(avg+(1-avg)*(0.6+contr/250.0)); // value at shoulder point
contrastcurvePoints.push_back(1.); // white point
contrastcurvePoints.push_back(1.); // value at white point
DiagonalCurve* contrastcurve = new DiagonalCurve (contrastcurvePoints, CURVES_MIN_POLY_POINTS/skip);
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
// apply contrast enhancement
for (int i=0; i<32768; i++) {
dcurve[i] = contrastcurve->getVal (dcurve[i]);
}
delete contrastcurve;
}
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
// create a curve if needed
DiagonalCurve* tcurve = NULL;
bool histNeeded = false;
if (curvePoints.size()>0 && curvePoints[0]!=0) {
tcurve = new DiagonalCurve (curvePoints, CURVES_MIN_POLY_POINTS/skip);
if (outBeforeCCurveHistogram /*&& histogramCropped*/)
histNeeded = true;
}
if (tcurve && tcurve->isIdentity()) {
delete tcurve;
tcurve = NULL;
}
if (tcurve) {
// L values go up to 32767, last stop is for highlight overflow
for (int i=0; i<32768; i++) {
float val;
if (histNeeded) {
float hval = dcurve[i];
int hi = (int)(255.0*CLIPD(hval));
outBeforeCCurveHistogram[hi]+=histogram/*Cropped*/[i] ;
}
// apply custom/parametric/NURBS curve, if any
val = tcurve->getVal (dcurve[i]);
outCurve[i] = (32767.0 * val);
}
}
else {
// Skip the slow getval method if no curve is used (or an identity curve)
// L values go up to 32767, last stop is for highlight overflow
for (int i=0; i<32768; i++) {
if (histNeeded) {
float hval = dcurve[i];
int hi = (int)(255.0*CLIPD(hval));
outBeforeCCurveHistogram[hi]+=histogram/*Cropped*/[i] ;
}
outCurve[i] = 32767.0*dcurve[i];
}
}
for (int i=32768; i<65536; i++) outCurve[i]=(float)i;
if (tcurve)
delete tcurve;
/*if (outBeforeCCurveHistogram) {
for (int i=0; i<256; i++) printf("i= %d bchist= %d \n",i,outBeforeCCurveHistogram[i]);
}*/
}
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
void CurveFactory::RGBCurve (const std::vector<double>& curvePoints, LUTf & outCurve, int skip) {
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
// create a curve if needed
DiagonalCurve* tcurve = NULL;
bool histNeeded = false;
if (curvePoints.size()>0 && curvePoints[0]!=0) {
tcurve = new DiagonalCurve (curvePoints, CURVES_MIN_POLY_POINTS/skip);
}
if (tcurve && tcurve->isIdentity()) {
delete tcurve;
tcurve = NULL;
}
if (tcurve) {
for (int i=0; i<65536; i++) {
// apply custom/parametric/NURBS curve, if any
float val = tcurve->getVal ((float)i/65536.0f);
outCurve[i] = (65536.0f * val);
}
}
else {
// Skip the slow getval method if no curve is used (or an identity curve)
for (int i=0; i<65536; i++) {
outCurve[i] = i;
}
}
if (tcurve)
delete tcurve;
}
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
LUTf CurveFactory::gammatab;
LUTf CurveFactory::igammatab_srgb;
LUTf CurveFactory::gammatab_srgb;
void CurveFactory::init () {
gammatab(65536,0);
igammatab_srgb(65536,0);
gammatab_srgb(65536,0);
for (int i=0; i<65536; i++)
gammatab_srgb[i] = (65535.0 * gamma2 (i/65535.0));
for (int i=0; i<65536; i++)
igammatab_srgb[i] = (65535.0 * igamma2 (i/65535.0));
for (int i=0; i<65536; i++)
gammatab[i] = (65535.0 * pow (i/65535.0, 0.454545));
/* FILE* f = fopen ("c.txt", "wt");
for (int i=0; i<256; i++)
fprintf (f, "%g %g\n", i/255.0, clower (i/255.0, 2.0, 1.0));
fclose (f);*/
}
}