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/mcf_levelsets3d.cpp b/examples/mcf_levelsets3d.cpp
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+/*
+ #
+ # File : mcf_levelsets3d.cpp
+ # ( C++ source file )
+ #
+ # Description : Implementation of the Mean Curvature Flow on Surfaces
+ # using the framework of Level Sets 3D.
+ # 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"
+using namespace cimg_library;
+#undef min
+#undef max
+
+// Apply the Mean curvature flow PDE
+//-----------------------------------
+template<typename T> CImg<T>& mcf_PDE(CImg<T>& img, const unsigned int nb_iterations,
+ const float dt=0.25f, const float narrow=4.0f) {
+ CImg<float> velocity(img.width(),img.height(),img.depth(),img.spectrum());
+ CImg_3x3x3(I,float);
+ for (unsigned int iteration = 0; iteration<nb_iterations; ++iteration) {
+ float *ptrd = velocity.data(), veloc_max = 0;
+ cimg_for3x3x3(img,x,y,z,0,I,float) if (cimg::abs(Iccc)<narrow) {
+ const float
+ ix = (Incc - Ipcc)/2,
+ iy = (Icnc - Icpc)/2,
+ iz = (Iccn - Iccp)/2,
+ norm = (float)std::sqrt(1e-5f + ix*ix + iy*iy + iz*iz),
+ ixx = Incc + Ipcc - 2*Iccc,
+ ixy = (Ippc + Innc - Inpc - Ipnc)/4,
+ ixz = (Ipcp + Incn - Incp - Ipcn)/4,
+ iyy = Icnc + Icpc - 2*Iccc,
+ iyz = (Icpp + Icnn - Icnp - Icpn)/4,
+ izz = Iccn + Iccp - 2*Iccc,
+ a = ix/norm,
+ b = iy/norm,
+ c = iz/norm,
+ inn = a*a*ixx + b*b*iyy + c*c*izz + 2*a*b*ixy + 2*a*c*ixz + 2*b*c*iyz,
+ veloc = ixx + iyy + izz - inn;
+ *(ptrd++) = veloc;
+ if (veloc>veloc_max) veloc_max = veloc; else if (-veloc>veloc_max) veloc_max = -veloc;
+ } else *(ptrd++) = 0;
+ if (veloc_max>0) img+=(velocity*=dt/veloc_max);
+ }
+ return img;
+}
+
+/*----------------------
+
+ Main procedure
+
+ --------------------*/
+int main(int argc,char **argv) {
+ cimg_usage("Mean curvature flow of a surface, using 3D level sets");
+ const char *file_i = cimg_option("-i",(char*)0,"Input image");
+ const float dt = cimg_option("-dt",0.05f,"PDE Time step");
+ const float narrow = cimg_option("-band",5.0f,"Size of the narrow band");
+ const bool both = cimg_option("-both",false,"Show both evolving and initial surface");
+
+ // Define the signed distance map of the initial surface.
+ CImg<> img;
+ if (file_i) {
+ const float sigma = cimg_option("-sigma",1.2f,"Segmentation regularity");
+ const float alpha = cimg_option("-alpha",5.0f,"Region growing tolerance");
+ img.load(file_i).channel(0);
+ CImg<int> s;
+ CImgDisplay disp(img,"Please select a starting point");
+ while (!s || s[0]<0) s = img.get_select(0,disp);
+ CImg<> region;
+ float tmp[] = { 0 };
+ img.draw_fill(s[0],s[1],s[2],tmp,1,region,alpha);
+ ((img = region.normalize(-1,1))*=-1).blur(sigma);
+ }
+ else { // Create synthetic implicit function
+ img.assign(60,60,60);
+ const float exte[] = { 1 }, inte[] = { -1 };
+ img.fill(*exte).draw_rectangle(15,15,15,45,45,45,inte).draw_rectangle(25,25,0,35,35,img.depth() - 1,exte).
+ draw_rectangle(0,25,25,img.width() - 1,35,35,exte).draw_rectangle(25,0,25,35,img.height() - 1,35,exte).noise(0.7);
+ }
+ img.distance_eikonal(10,0,0.1f);
+
+ // Compute corresponding surface triangularization by the marching cube algorithm (isovalue 0).
+ CImg<> points0;
+ CImgList<unsigned int> faces0;
+ if (both) points0 = img.get_isosurface3d(faces0,0);
+ const CImgList<unsigned char> colors0(faces0.size(),CImg<unsigned char>::vector(100,200,255));
+ const CImgList<> opacities0(faces0.size(),1,1,1,1,0.2f);
+
+ // Perform MCF evolution.
+ CImgDisplay disp(256,256,0,1), disp3d(512,512,0,0);
+ float alpha = 0, beta = 0;
+ for (unsigned int iteration = 0; !disp.is_closed() && !disp3d.is_closed() &&
+ !disp.is_keyESC() && !disp3d.is_keyESC() && !disp.is_keyQ() && !disp3d.is_keyQ(); ++iteration) {
+ disp.set_title("3D implicit Function (iter. %u)",iteration);
+ disp3d.set_title("Mean curvature flow 3D - Isosurface (iter. %u)",iteration);
+
+ // Apply PDE on the distance function.
+ mcf_PDE(img,1,dt,narrow); // Do one iteration of mean curvature flow
+ // Every 10 steps, do one iteration of distance function re-initialization.
+ if (!(iteration%10)) img.distance_eikonal(1,narrow,0.5f);
+
+ // Compute surface triangularization by the marching cube algorithm (isovalue 0)
+ CImgList<unsigned int> faces;
+ CImg<> points = img.get_isosurface3d(faces,0);
+ CImgList<unsigned char> colors(faces.size(),CImg<unsigned char>::vector(200,128,100));
+ CImgList<> opacities(faces.size(),CImg<>::vector(1.0f));
+ const float fact = 3*std::max(disp3d.width(),disp3d.height())/(4.0f*std::max(img.width(),img.height()));
+
+ // Append initial object if necessary.
+ if (both) {
+ points.append_object3d(faces,points0,faces0);
+ colors.insert(colors0);
+ opacities.insert(opacities0);
+ }
+
+ // Center and rescale the objects
+ cimg_forX(points,l) {
+ points(l,0)=(points(l,0) - img.width()/2)*fact;
+ points(l,1)=(points(l,1) - img.height()/2)*fact;
+ points(l,2)=(points(l,2) - img.depth()/2)*fact;
+ }
+
+ // Display 3D object on the display window.
+ CImg<unsigned char> visu(disp3d.width(),disp3d.height(),1,3,0);
+ const CImg<> rot = CImg<>::rotation_matrix(1,0,0,(beta+=0.5f))*CImg<>::rotation_matrix(0,1,1,(alpha+=3));
+ if (points.size()) {
+ visu.draw_object3d(visu.width()/2.0f,visu.height()/2.0f,0.0f,
+ rot*points,faces,colors,opacities,3,
+ false,500.0,0.0f,0.0f,-8000.0f).display(disp3d);
+ } else visu.fill(0).display(disp3d);
+ img.display(disp.wait(20));
+
+ if ((disp3d.button() || disp3d.key()) && points.size() && !disp3d.is_keyESC() && !disp3d.is_keyQ()) {
+ const unsigned char white[3] = { 255, 255, 255 };
+ visu.fill(0).draw_text(10,10,"Time stopped, press any key to start again",white).
+ display_object3d(disp3d,points,faces,colors,opacities,true,4,3,false,500,0,0,-5000,0.4f,0.3f);
+ disp3d.set_key();
+ }
+ if (disp.is_resized()) disp.resize(false);
+ if (disp3d.is_resized()) disp3d.resize(false);
+ disp.wait(50);
+ }
+
+ return 0;
+}