CGAL 5.3.2 - Classification
Classification/example_mesh_classification.cpp
#if defined (_MSC_VER) && !defined (_WIN64)
#pragma warning(disable:4244) // boost::number_distance::distance()
// converts 64 to 32 bits integers
#endif
#include <CGAL/Simple_cartesian.h>
#include <CGAL/Surface_mesh.h>
#include <CGAL/Classification.h>
#include <CGAL/Real_timer.h>
#include <cstdlib>
#include <fstream>
#include <iostream>
#include <string>
typedef Kernel::Point_3 Point;
typedef CGAL::Surface_mesh<Point> Mesh;
namespace Classification = CGAL::Classification;
typedef Classification::Label_handle Label_handle;
typedef Classification::Feature_handle Feature_handle;
typedef Classification::Label_set Label_set;
typedef Classification::Feature_set Feature_set;
typedef Classification::Face_descriptor_to_center_of_mass_map<Mesh> Face_point_map;
typedef Classification::Face_descriptor_to_face_descriptor_with_bbox_map<Mesh> Face_with_bbox_map;
typedef Classification::Mesh_feature_generator<Kernel, Mesh, Face_point_map> Feature_generator;
int main (int argc, char** argv)
{
std::string filename = "data/b9_mesh.off";
std::string filename_config = "data/b9_mesh_config.bin";
if (argc > 1)
filename = argv[1];
if (argc > 2)
filename_config = argv[2];
Mesh mesh;
if(!CGAL::IO::read_polygon_mesh(filename, mesh,
// the PLY reader expects a binary file by default
CGAL::parameters::use_binary_mode(false)))
{
std::cerr << "Invalid input." << std::endl;
return 1;
}
std::cerr << "Generating features" << std::endl;
CGAL::Real_timer t;
t.start();
Feature_set features;
Face_point_map face_point_map (&mesh); // Associates each face to its center of mass
std::size_t number_of_scales = 5;
Feature_generator generator (mesh, face_point_map, number_of_scales);
features.begin_parallel_additions();
generator.generate_point_based_features (features); // Features that consider the mesh as a point set
generator.generate_face_based_features (features); // Features computed directly on mesh faces
features.end_parallel_additions();
t.stop();
std::cerr << "Done in " << t.time() << " second(s)" << std::endl;
Label_set labels = { "ground", "vegetation", "roof" };
std::vector<int> label_indices(mesh.number_of_faces(), -1);
std::cerr << "Using ETHZ Random Forest Classifier" << std::endl;
Classification::ETHZ::Random_forest_classifier classifier (labels, features);
std::cerr << "Loading configuration" << std::endl;
std::ifstream in_config (filename_config, std::ios_base::in | std::ios_base::binary);
classifier.load_configuration (in_config);
std::cerr << "Classifying with graphcut" << std::endl;
t.reset();
t.start();
Classification::classify_with_graphcut<CGAL::Parallel_if_available_tag>
(mesh.faces(), Face_with_bbox_map(&mesh), labels, classifier,
generator.neighborhood().n_ring_neighbor_query(2),
0.2f, 1, label_indices);
t.stop();
std::cerr << "Classification with graphcut done in " << t.time() << " second(s)" << std::endl;
return EXIT_SUCCESS;
}