103 lines
3.7 KiB
C++
103 lines
3.7 KiB
C++
// This file is part of libigl, a simple c++ geometry processing library.
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//
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// Copyright (C) 2013 Alec Jacobson <alecjacobson@gmail.com>
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//
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// This Source Code Form is subject to the terms of the Mozilla Public License
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// v. 2.0. If a copy of the MPL was not distributed with this file, You can
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// obtain one at http://mozilla.org/MPL/2.0/.
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#include "rgb_to_hsv.h"
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template <typename R,typename H>
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IGL_INLINE void igl::rgb_to_hsv(const R * rgb, H * hsv)
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{
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// http://en.literateprograms.org/RGB_to_HSV_color_space_conversion_%28C%29
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R rgb_max = 0.0;
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R rgb_min = 1.0;
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rgb_max = (rgb[0]>rgb_max?rgb[0]:rgb_max);
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rgb_max = (rgb[1]>rgb_max?rgb[1]:rgb_max);
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rgb_max = (rgb[2]>rgb_max?rgb[2]:rgb_max);
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rgb_min = (rgb[0]<rgb_min?rgb[0]:rgb_min);
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rgb_min = (rgb[1]<rgb_min?rgb[1]:rgb_min);
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rgb_min = (rgb[2]<rgb_min?rgb[2]:rgb_min);
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//hsv[2] = rgb_max;
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hsv[2] = rgb_max;
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if(hsv[2] == 0)
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{
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hsv[0]=hsv[1]=0;
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return;
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}
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// normalize
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R rgb_n[3];
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rgb_n[0] = rgb[0]/hsv[2];
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rgb_n[1] = rgb[1]/hsv[2];
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rgb_n[2] = rgb[2]/hsv[2];
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// Recomput max min?
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rgb_max = 0;
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rgb_max = (rgb_n[0]>rgb_max?rgb_n[0]:rgb_max);
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rgb_max = (rgb_n[1]>rgb_max?rgb_n[1]:rgb_max);
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rgb_max = (rgb_n[2]>rgb_max?rgb_n[2]:rgb_max);
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rgb_min = 1;
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rgb_min = (rgb_n[0]<rgb_min?rgb_n[0]:rgb_min);
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rgb_min = (rgb_n[1]<rgb_min?rgb_n[1]:rgb_min);
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rgb_min = (rgb_n[2]<rgb_min?rgb_n[2]:rgb_min);
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hsv[1] = rgb_max - rgb_min;
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if(hsv[1] == 0)
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{
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hsv[0] = 0;
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return;
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}
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rgb_n[0] = (rgb_n[0] - rgb_min)/(rgb_max - rgb_min);
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rgb_n[1] = (rgb_n[1] - rgb_min)/(rgb_max - rgb_min);
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rgb_n[2] = (rgb_n[2] - rgb_min)/(rgb_max - rgb_min);
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// Recomput max min?
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rgb_max = 0;
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rgb_max = (rgb_n[0]>rgb_max?rgb_n[0]:rgb_max);
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rgb_max = (rgb_n[1]>rgb_max?rgb_n[1]:rgb_max);
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rgb_max = (rgb_n[2]>rgb_max?rgb_n[2]:rgb_max);
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rgb_min = 1;
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rgb_min = (rgb_n[0]<rgb_min?rgb_n[0]:rgb_min);
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rgb_min = (rgb_n[1]<rgb_min?rgb_n[1]:rgb_min);
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rgb_min = (rgb_n[2]<rgb_min?rgb_n[2]:rgb_min);
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if (rgb_max == rgb_n[0]) {
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hsv[0] = 0.0 + 60.0*(rgb_n[1] - rgb_n[2]);
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if (hsv[0] < 0.0) {
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hsv[0] += 360.0;
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}
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} else if (rgb_max == rgb_n[1]) {
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hsv[0] = 120.0 + 60.0*(rgb_n[2] - rgb_n[0]);
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} else /* rgb_max == rgb_n[2] */ {
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hsv[0] = 240.0 + 60.0*(rgb_n[0] - rgb_n[1]);
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}
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}
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template <typename DerivedR,typename DerivedH>
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IGL_INLINE void igl::rgb_to_hsv(
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const Eigen::PlainObjectBase<DerivedR> & R,
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Eigen::PlainObjectBase<DerivedH> & H)
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{
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assert(R.cols() == 3);
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H.resizeLike(R);
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for(typename DerivedR::Index r = 0;r<R.rows();r++)
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{
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typename DerivedR::Scalar rgb[3];
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rgb[0] = R(r,0);
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rgb[1] = R(r,1);
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rgb[2] = R(r,2);
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typename DerivedH::Scalar hsv[] = {0,0,0};
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rgb_to_hsv(rgb,hsv);
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H(r,0) = hsv[0];
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H(r,1) = hsv[1];
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H(r,2) = hsv[2];
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}
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}
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#ifdef IGL_STATIC_LIBRARY
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// Explicit template instantiation
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template void igl::rgb_to_hsv<float, double>(float const*, double*);
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template void igl::rgb_to_hsv<double, double>(double const*, double*);
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template void igl::rgb_to_hsv<Eigen::Matrix<double, -1, -1, 0, -1, -1>, Eigen::Matrix<double, -1, -1, 0, -1, -1> >(Eigen::PlainObjectBase<Eigen::Matrix<double, -1, -1, 0, -1, -1> > const&, Eigen::PlainObjectBase<Eigen::Matrix<double, -1, -1, 0, -1, -1> >&);
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template void igl::rgb_to_hsv<Eigen::Matrix<float, -1, -1, 0, -1, -1>, Eigen::Matrix<float, -1, -1, 0, -1, -1> >(Eigen::PlainObjectBase<Eigen::Matrix<float, -1, -1, 0, -1, -1> > const&, Eigen::PlainObjectBase<Eigen::Matrix<float, -1, -1, 0, -1, -1> >&);
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template void igl::rgb_to_hsv<Eigen::Matrix<float, 64, 3, 1, 64, 3>, Eigen::Matrix<float, 64, 3, 1, 64, 3> >(Eigen::PlainObjectBase<Eigen::Matrix<float, 64, 3, 1, 64, 3> > const&, Eigen::PlainObjectBase<Eigen::Matrix<float, 64, 3, 1, 64, 3> >&);
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#endif
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