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git-subtree-split: 4b66369ab4e34a46119d6c43e9adce061bb40f4b
diff --git a/examples/use_skeleton.cpp b/examples/use_skeleton.cpp
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+/*
+ #
+ # File : use_skeleton.cpp
+ # ( C++ source file )
+ #
+ # Description : Example of use for the CImg plugin 'plugins/skeleton.h'.
+ # This file is a part of the CImg Library project.
+ # ( http://cimg.eu )
+ #
+ # Copyright : Francois-Xavier Dupe
+ # ( http://www.greyc.ensicaen.fr/~fdupe/ )
+ #
+ # 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 <queue>
+#define cimg_plugin "plugins/skeleton.h"
+#include "CImg.h"
+using namespace cimg_library;
+#ifndef cimg_imagepath
+#define cimg_imagepath "img/"
+#endif
+
+// Main procedure
+//----------------
+int main (int argc, char **argv) {
+
+ cimg_usage("Compute the skeleton of a shape, using Hamilton-Jacobi equations");
+
+ // Read command line arguments
+ cimg_help("Input/Output options\n"
+ "--------------------");
+ const char* file_i = cimg_option("-i",cimg_imagepath "milla.bmp","Input (black&white) image");
+ const int median = cimg_option("-median",0,"Apply median filter");
+ const bool invert = cimg_option("-inv",false,"Invert image values");
+ const char* file_o = cimg_option("-o",(char*)0,"Output skeleton image");
+ const bool display = cimg_option("-visu",true,"Display results");
+
+ cimg_help("Skeleton computation parameters\n"
+ "-------------------------------");
+ const float thresh = cimg_option("-t",-0.3f,"Threshold");
+ const bool curve = cimg_option("-curve",false,"Create medial curve");
+
+ cimg_help("Torsello correction parameters\n"
+ "------------------------------");
+ const bool correction = cimg_option("-corr",false,"Torsello correction");
+ const float dlt1 = 2;
+ const float dlt2 = cimg_option("-dlt",1.0f,"Discrete step");
+
+ // Load the image (forcing it to be scalar with 2 values { 0,1 }).
+ CImg<unsigned int> image0(file_i), image = image0.get_norm().quantize(2).normalize(0.0f,1.0f).round();
+ if (median) image.blur_median(median);
+ if (invert) (image-=1)*=-1;
+ if (display) (image0.get_normalize(0,255),image.get_normalize(0,255)).display("Input image - Binary image");
+
+ // Compute distance map.
+ CImgList<float> visu;
+ CImg<float> distance = image.get_distance(0);
+ if (display) visu.insert(distance);
+
+ // Compute the gradient of the distance function, and the flux (divergence) of the gradient field.
+ const CImgList<float> grad = distance.get_gradient("xyz");
+ CImg<float> flux = image.get_flux(grad,1,1);
+ if (display) visu.insert(flux);
+
+ // Use the Torsello correction of the flux if necessary.
+ if (correction) {
+ CImg<float>
+ logdensity = image.get_logdensity(distance,grad,flux,dlt1),
+ nflux = image.get_corrected_flux(logdensity,grad,flux,dlt2);
+ if (display) visu.insert(logdensity).insert(nflux);
+ flux = nflux;
+ }
+
+ if (visu) {
+ cimglist_apply(visu,normalize)(0,255);
+ visu.display(visu.size()==2?"Distance function - Flux":"Distance function - Flux - Log-density - Corrected flux");
+ }
+
+ // Compute the skeleton
+ const CImg<unsigned int> skel = image.get_skeleton(flux,distance,curve,thresh);
+ if (display) {
+ (image0.resize(-100,-100,1,3)*=0.7f).get_shared_channel(1)|=skel*255.0;
+ image0.draw_image(0,0,0,0,image*255.0,0.5f).display("Image + Skeleton");
+ }
+
+ // Save output image if necessary.
+ if (file_o) skel.save(file_o);
+
+ return 0;
+}