Squashed 'third_party/cimg/' content from commit 4b66369

Change-Id: I7454d9107a08dba899fd4659731733049165ae0a
git-subtree-dir: third_party/cimg
git-subtree-split: 4b66369ab4e34a46119d6c43e9adce061bb40f4b
diff --git a/examples/fade_images.cpp b/examples/fade_images.cpp
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+/*
+ #
+ #  File        : fade_images.cpp
+ #                ( C++ source file )
+ #
+ #  Description : Compute a linear fading between two images.
+ #                This file is a part of the CImg Library project.
+ #                ( http://cimg.eu )
+ #
+ #  Copyright   : David Tschumperle
+ #                ( http://tschumperle.users.greyc.fr/ )
+ #
+ #  License     : CeCILL v2.0
+ #                ( http://www.cecill.info/licences/Licence_CeCILL_V2-en.html )
+ #
+ #  This software is governed by the CeCILL  license under French law and
+ #  abiding by the rules of distribution of free software.  You can  use,
+ #  modify and/ or redistribute the software under the terms of the CeCILL
+ #  license as circulated by CEA, CNRS and INRIA at the following URL
+ #  "http://www.cecill.info".
+ #
+ #  As a counterpart to the access to the source code and  rights to copy,
+ #  modify and redistribute granted by the license, users are provided only
+ #  with a limited warranty  and the software's author,  the holder of the
+ #  economic rights,  and the successive licensors  have only  limited
+ #  liability.
+ #
+ #  In this respect, the user's attention is drawn to the risks associated
+ #  with loading,  using,  modifying and/or developing or reproducing the
+ #  software by the user in light of its specific status of free software,
+ #  that may mean  that it is complicated to manipulate,  and  that  also
+ #  therefore means  that it is reserved for developers  and  experienced
+ #  professionals having in-depth computer knowledge. Users are therefore
+ #  encouraged to load and test the software's suitability as regards their
+ #  requirements in conditions enabling the security of their systems and/or
+ #  data to be ensured and,  more generally, to use and operate it in the
+ #  same conditions as regards security.
+ #
+ #  The fact that you are presently reading this means that you have had
+ #  knowledge of the CeCILL license and that you accept its terms.
+ #
+*/
+
+#include "CImg.h"
+#ifndef cimg_imagepath
+#define cimg_imagepath "img/"
+#endif
+#undef min
+#undef max
+
+// Main procedure
+//---------------
+int main(int argc,char **argv) {
+
+  // Read and check command line parameters.
+  cimg_usage("Compute a linear fading between two 2D images");
+  const char *file_i1 = cimg_option("-i1",cimg_imagepath "sh0r.pgm","Input Image 1");
+  const char *file_i2 = cimg_option("-i2",cimg_imagepath "milla.bmp","Input Image 2");
+  const char *file_o  = cimg_option("-o",(char*)0,"Output Image");
+  const bool visu     = cimg_option("-visu",true,"Visualization mode");
+  const double pmin   = cimg_option("-min",40.0,"Begin of the fade (in %)")/100.0;
+  const double pmax   = cimg_option("-max",60.0,"End of the fade (in %)")/100.0;
+  const double angle  = cimg_option("-angle",0.0,"Fade angle")*cil::cimg::PI/180;
+
+  // Init images.
+  cil::CImg<unsigned char> img1(file_i1), img2(file_i2);
+  if (!img2.is_sameXYZC(img1)) {
+    int
+      dx = std::max(img1.width(),img2.width()),
+      dy = std::max(img1.height(),img2.height()),
+      dz = std::max(img1.depth(),img2.depth()),
+      dv = std::max(img1.spectrum(),img2.spectrum());
+    img1.resize(dx,dy,dz,dv,3);
+    img2.resize(dx,dy,dz,dv,3);
+  }
+  cil::CImg<unsigned char> dest(img1);
+
+  // Compute the faded image.
+  const double ca = std::cos(angle), sa = std::sin(angle);
+  double alpha;
+  cimg_forXYZC(dest,x,y,z,k) {
+    const double X = ((double)x/img1.width() - 0.5)*ca + ((double)y/img1.height() - 0.5)*sa;
+    if (X + 0.5<pmin) alpha = 0; else {
+      if (X + 0.5>pmax) alpha = 1; else
+        alpha = (X + 0.5 - pmin)/(pmax - pmin);
+    }
+    dest(x,y,z,k) = (unsigned char)((1 - alpha)*img1(x,y,z,k) + alpha*img2(x,y,z,k));
+  }
+
+  // Save and exit
+  if (file_o) dest.save(file_o);
+  if (visu) dest.display("Image fading");
+  return 0;
+}