////////////////////////////////////////////////////////////////
//
//          combined AMaZE + VNG4 demosaic algorithm
//
//
//  copyright (c) 2018  Ingo Weyrich <heckflosse67@gmx.de>
//
//  blends AMaZE and VNG4 output based on contrast
//
//
//  amaze_vng4_demosaic_RT.cc 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.
//
//  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, see <http://www.gnu.org/licenses/>.
//
////////////////////////////////////////////////////////////////

#include "rtengine.h"
#include "rawimagesource.h"
#include "rt_math.h"
#define BENCHMARK
#include "StopWatch.h"
#include "rt_algo.h"

using namespace std;

namespace rtengine
{

void RawImageSource::amaze_vng4_demosaic_RT(int winw, int winh, const array2D<float> &rawData, array2D<float> &red, array2D<float> &green, array2D<float> &blue, double contrast)
{
    BENCHFUN

    if (contrast == 0.0) {
        // contrast == 0.0 means only AMaZE will be used
        amaze_demosaic_RT(0, 0, winw, winh, rawData, red, green, blue);
        return;
    }

    vng4_demosaic(rawData, red, green, blue);

    array2D<float> redTmp(winw, winh);
    array2D<float> greenTmp(winw, winh);
    array2D<float> blueTmp(winw, winh);
    array2D<float> L(winw, winh);

    amaze_demosaic_RT(0, 0, winw, winh, rawData, redTmp, greenTmp, blueTmp);
    const float xyz_rgb[3][3] = {          // XYZ from RGB
                                { 0.412453, 0.357580, 0.180423 },
                                { 0.212671, 0.715160, 0.072169 },
                                { 0.019334, 0.119193, 0.950227 }
                                };
    #pragma omp parallel
    {
        #pragma omp for
        for(int i = 0; i < winh; ++i) {
            Color::RGB2L(redTmp[i], greenTmp[i], blueTmp[i], L[i], xyz_rgb, winw);
        }
    }
    // calculate contrast based blend factors to use vng4 in regions with low contrast
    JaggedArray<float> blend(winw, winh);
    buildBlendMask(L, blend, winw, winh, contrast / 100.f);

    // the following is split into 3 loops intentionally to avoid cache conflicts on CPUs with only 4-way cache
    #pragma omp parallel for
    for(int i = 0; i < winh; ++i) {
        for(int j = 0; j < winw; ++j) {
            red[i][j] = intp(blend[i][j], redTmp[i][j], red[i][j]);
        }
    }
    #pragma omp parallel for
    for(int i = 0; i < winh; ++i) {
        for(int j = 0; j < winw; ++j) {
            green[i][j] = intp(blend[i][j], greenTmp[i][j], green[i][j]);
        }
    }
    #pragma omp parallel for
    for(int i = 0; i < winh; ++i) {
        for(int j = 0; j < winw; ++j) {
            blue[i][j] = intp(blend[i][j], blueTmp[i][j], blue[i][j]);
        }
    }

}
}