Src/Operators/ReinhardGlobalOperator/ReinhardGlobalOperator.cpp

//      ReinhardGlobalOperator.cpp
//      
//      Copyright 2010 Jérémy Laumon <jeremy.laumon@gmail.com>
//      
//      This program 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 2 of the License, or
//      (at your option) any later version.
//      
//      This program 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 this program; if not, write to the Free Software
//      Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
//      MA 02110-1301, USA.


#include <ReinhardGlobalOperator.h>
#include <Exceptions.h>
#include <math.h>

#define OPERATOR_NAME "Reinhard Global Operator"

Q_EXPORT_PLUGIN2(TT_ReinhardGlobalOperator, ReinhardGlobalOperatorFactory)


ReinhardGlobalOperator::ReinhardGlobalOperator() :
    inputImage(NULL),
    outputImage(NULL),
    avLum(0.0),
    keyValue(0.18),
    burnOut(false),
    lumWhite2(1.0)
{
    
}

void ReinhardGlobalOperator::setupUi(QWidget* parent)
{
    ui.setupUi(parent);
    
    connect(ui.keyValueSlider, SIGNAL(sliderReleased()), this, SLOT(toneMap()));
    connect(ui.keyValueSlider, SIGNAL(valueChanged(int)), this, SLOT(updateKeyValue(int)));
    connect(ui.burnOutGroupBox, SIGNAL(toggled(bool)), this, SLOT(updateBurnOut(bool)));
    connect(ui.whiteValueSpinBox, SIGNAL(editingFinished()), this, SLOT(updateLumWhite()));
    connect(ui.whiteValueOkButton, SIGNAL(clicked()), this, SLOT(toneMap()));
}

QString ReinhardGlobalOperator::name() const
{
    return tr(OPERATOR_NAME);
}

const HdrImage* ReinhardGlobalOperator::getToneMappedImage() const
{
    return outputImage;
}

void ReinhardGlobalOperator::setImage(const HdrImage* image)
{
    if (!image->hasY())
        throw Exception(tr("Image passed to %1 does not contains Y data. Cannot turn water into wine.").arg(name()));
    
    QTime t;
    t.start();
    
    inputImage = image;
    QSize size = inputImage->size();
    delete outputImage;
    outputImage = new HdrImage(*inputImage);
    const double delta = 0.0001;
    
    float lumMax = 0.0;
    int Y = inputImage->YIndex();
    avLum = 0.0;
    for(int i=0; i<size.height(); ++i)
        for(int j=0; j<size.width(); ++j)
        {
            double lum = qMax(double((*inputImage)[i][j][Y]),0.0);
            avLum += log(delta + lum);
            lumMax = qMax(lumMax,float(lum));
        }
    avLum = exp(avLum/(double)(size.width()*size.height()));
    
    ui.whiteValueSpinBox->setMaximum(qMin(lumMax,float(1e19)));
    ui.whiteValueSpinBox->setValue(qMin(lumMax,float(1e19)));
    ui.keyValueSlider->setValue(18); // = 0.18
    ui.burnOutGroupBox->setChecked(false);
    
    msg = tr("Operator Init: %1 ms").arg(t.elapsed());
    
    toneMap();
}

void ReinhardGlobalOperator::toneMap()
{
    if (inputImage)
    {
        QTime t;
        t.start();
        
        QSize size = inputImage->size();
        int width = size.width();
        int height = size.height();
        int Y = inputImage->YIndex();
        
        if(burnOut)
            for(int i=0; i<height; ++i)
                for(int j=0; j<width; ++j)
                {
                    float lum = (*inputImage)[i][j][Y];
                    lum = keyValue*lum/avLum;
                    (*outputImage)[i][j][Y] = lum*(1.0+(lum/lumWhite2))/(1.0+lum);

                }
        else
            for(int i=0; i<height; ++i)
                for(int j=0; j<width; ++j)
                {
                    float lum = (*inputImage)[i][j][Y];
                    lum = keyValue*lum/avLum;
                    (*outputImage)[i][j][Y] = lum/(1.0+lum);

                }
        
        emit message(msg + tr("  Tone Mapping: %1 ms").arg(t.elapsed()));
                
        emit imageUpdated();
    }
}

void ReinhardGlobalOperator::updateKeyValue(int value)
{
    keyValue = float(value)/100.0;
    ui.keyValue->setText(QString("%1").arg(keyValue, 0, 'f', 2));
}

void ReinhardGlobalOperator::updateBurnOut(bool enabled)
{
    burnOut = enabled;
    updateLumWhite();
}

void ReinhardGlobalOperator::updateLumWhite()
{
    float value = ui.whiteValueSpinBox->value();
    lumWhite2 = value*value;
    toneMap();
}

//----------------------------------------------------------------------

ToneMappingOperatorPtr ReinhardGlobalOperatorFactory::createOperator() const
{
    return ToneMappingOperatorPtr(new ReinhardGlobalOperator);
}

QString ReinhardGlobalOperatorFactory::operatorName() const
{
    return tr(OPERATOR_NAME);
}