colorspace.cpp

/****************************************************************************
* VCGLib                                                            o o     *
* Visual and Computer Graphics Library                            o     o   *
*                                                                _   O  _   *
* Copyright(C) 2004-2016                                           \/)\/    *
* Visual Computing Lab                                            /\/|      *
* ISTI - Italian National Research Council                           |      *
*                                                                    \      *
* All rights reserved.                                                      *
*                                                                           *
* 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 (http://www.gnu.org/licenses/gpl.txt)          *
* for more details.                                                         *
*                                                                           *
****************************************************************************/

// Standard headers
#include <iostream>

// VCG headers
#include <vcg/space/color4.h>
#include <vcg/space/colorspace.h>

using namespace std;

typedef vcg::ColorSpace<double> ColorSpace;

int main(int argc,char ** argv)
{
        // Some Color Space processing examples

        cout << endl;

        if (argc != 4)
        {
                cout << "  Usage: colorspace <r> <g> <b>" << endl << endl;
                cout << "         <r> <g> <b> : RGB triplet (0-255)" << endl << endl;
                cout << "         Note: The RGB triplet is assumed in the sRGB space (D65 illuminant).";
                cout << endl << endl;
                exit(-2);
        }

        double r = static_cast<double>(atof(argv[1]));
        double g = static_cast<double>(atof(argv[2]));
        double b = static_cast<double>(atof(argv[3]));

        // RGB components have to be in the range [0.0, 1.0]
        vcg::Color4<double> color(r/255.0, g/255.0, b/255.0, 0.0);


        // RGB --> RGB (RGB space changing)

        cout << "  * RGB --> RGB conversion" << endl << endl;

        vcg::Color4<double> rgb = ColorSpace::RGBtoRGB(color, ColorSpace::SRGB, ColorSpace::PAL_RGB);
        rgb *= 255.0;
        cout << "  RGB (PAL/SECAM): " << rgb[0] << " " << rgb[1] << " " << rgb[2] << endl;
        
        rgb = ColorSpace::RGBtoRGB(color, ColorSpace::SRGB, ColorSpace::WIDE_GAMUT);
        rgb *= 255.0;
        cout << "  RGB (Wide Gamut): " << rgb[0] << " " << rgb[1] << " " << rgb[2] << endl << endl;

        
        // RGB <--> HSL (Hue, Saturation, Lightness)

        cout << "  * RGB <--> HSL conversion" << endl << endl;

        vcg::Color4<double> hsl = ColorSpace::RGBtoHSL(color);
        cout << "  RGB --> HSL: " << hsl[0]*360.0 << "° " << hsl[1]*100.0 << "% " << hsl[2]*100.0 << "% " << endl;

        rgb = ColorSpace::HSLtoRGB(hsl);
        rgb *= 255.0;
        cout << "  HSL --> RGB: " << rgb[0] << " " << rgb[1] << " " << rgb[2] << endl << endl;


        // RGB <--> HSV (Hue, Saturation, Value)

        cout << "  * RGB <--> HSV conversion" << endl << endl;

        vcg::Color4<double> hsv = ColorSpace::RGBtoHSV(color);
        cout << "  RGB --> HSV: " << hsv[0]*360.0 << "° " << hsv[1]*100.0 << "% " << hsv[2]*100.0 << "% " <<  endl;

        rgb = ColorSpace::HSVtoRGB(hsv);
        rgb *= 255.0;
        cout << "  HSV --> RGB: " << rgb[0] << " " << rgb[1] << " " << rgb[2] << endl << endl;


        // RGB --> CIELab

        cout << "  * RGB <--> Lab conversion" << endl << endl;

        vcg::Color4<double> xyzD65 = ColorSpace::RGBtoXYZ(color, ColorSpace::SRGB, ColorSpace::VCG_ILLUMINANT_D65); 
        vcg::Color4<double> lab = ColorSpace::XYZtoCIELab(xyzD65, ColorSpace::refIlluminant(ColorSpace::SRGB));
        cout << "  RGB --> CIELab: " << lab[0] << " " << lab[1] << " " << lab[2] << endl;

        vcg::Color4<double> xyz = ColorSpace::CIELabtoXYZ(lab, ColorSpace::refIlluminant(ColorSpace::SRGB));
        rgb = ColorSpace::XYZtoRGB(xyz, ColorSpace::refIlluminant(ColorSpace::SRGB), ColorSpace::SRGB);
        rgb *= 255.0;
        cout << "  CIELab --> RGB: " << rgb[0] << " " << rgb[1] << " " << rgb[2] << endl << endl;



        // RGB <--> XYZ

        cout << "  * RGB <--> XYZ conversion" << endl << endl;

        // RGB --> XYZ (D65)
        cout << "  RGB --> XYZ (D65): " << xyzD65[0] << " " << xyzD65[1] << " " << xyzD65[2] << endl;

        // XYZ (D65) --> RGB
        rgb = ColorSpace::XYZtoRGB(xyzD65, ColorSpace::VCG_ILLUMINANT_D65, ColorSpace::SRGB);
        rgb *= 255.0;
        cout << "  XYZ (D65) --> RGB: " << rgb[0] << " " << rgb[1] << " " << rgb[2] << endl;

        // RGB --> XYZ (D50)
        vcg::Color4<double> xyzD50 = ColorSpace::RGBtoXYZ(color, ColorSpace::SRGB, ColorSpace::VCG_ILLUMINANT_D50);
        cout << "  RGB --> XYZ (D50): " << xyzD50[0] << " " << xyzD50[1] << " " << xyzD50[2] << endl;

        // XYZ (D50) --> RGB
        rgb = ColorSpace::XYZtoRGB(xyzD50, ColorSpace::VCG_ILLUMINANT_D50, ColorSpace::SRGB);
        rgb *= 255.0;
        cout << "  XYZ (D50) --> RGB: " << rgb[0] << " " << rgb[1] << " " << rgb[2] << endl;

        // Direct way
        xyz = ColorSpace::chromaticAdaptation(xyzD65, ColorSpace::VCG_ILLUMINANT_D65, ColorSpace::VCG_ILLUMINANT_D50);
        cout << "  XYZ (D65 --> D50): " << xyz[0] << " " << xyz[1] << " " << xyz[2] << endl << endl;

        return 0;
}