00001 /*************************************************************************** 00002 * Copyright (C) 1998-2008 by authors (see AUTHORS.txt ) * 00003 * * 00004 * This file is part of LuxRender. * 00005 * * 00006 * Lux Renderer is free software; you can redistribute it and/or modify * 00007 * it under the terms of the GNU General Public License as published by * 00008 * the Free Software Foundation; either version 3 of the License, or * 00009 * (at your option) any later version. * 00010 * * 00011 * Lux Renderer is distributed in the hope that it will be useful, * 00012 * but WITHOUT ANY WARRANTY; without even the implied warranty of * 00013 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * 00014 * GNU General Public License for more details. * 00015 * * 00016 * You should have received a copy of the GNU General Public License * 00017 * along with this program. If not, see <http://www.gnu.org/licenses/>. * 00018 * * 00019 * This project is based on PBRT ; see http://www.pbrt.org * 00020 * Lux Renderer website : http://www.luxrender.net * 00021 ***************************************************************************/ 00022 00023 // highcontrast.cpp* 00024 #include "tonemap.h" 00025 #include "mipmap.h" 00026 00027 namespace lux 00028 { 00029 00030 // HighContrastOp Declarations 00031 class HighContrastOp : public ToneMap { 00032 public: 00033 void Map(const float *y, 00034 int xRes, int yRes, 00035 float maxDisplayY, float *scale) const; 00036 00037 static ToneMap *CreateToneMap(const ParamSet &ps); 00038 private: 00039 // HighContrastOp Utility Methods 00040 static float C(float y) { 00041 if (y < 0.0034f) 00042 return y / 0.0014f; 00043 else if (y < 1) 00044 return 2.4483f + log10f(y/0.0034f)/0.4027f; 00045 else if (y < 7.2444f) 00046 return 16.563f + (y - 1)/0.4027f; 00047 else 00048 return 32.0693f + log10f(y / 7.2444f)/0.0556f; 00049 } 00050 static float T(float y, float CYmin, float CYmax, 00051 float maxDisplayY) { 00052 return maxDisplayY * (C(y) - CYmin) / (CYmax - CYmin); 00053 } 00054 }; 00055 00056 }//namespace lux 00057