CGAL 5.2.2 - Classification
Classification/example_generation_and_training.cpp
#if defined (_MSC_VER) && !defined (_WIN64)
#pragma warning(disable:4244) // boost::number_distance::distance()
// converts 64 to 32 bits integers
#endif
#include <cstdlib>
#include <fstream>
#include <iostream>
#include <string>
#include <CGAL/Simple_cartesian.h>
#include <CGAL/Classification.h>
#include <CGAL/Point_set_3.h>
#include <CGAL/Point_set_3/IO.h>
#include <CGAL/Real_timer.h>
typedef Kernel::Point_3 Point;
typedef CGAL::Point_set_3<Point> Point_set;
typedef Kernel::Iso_cuboid_3 Iso_cuboid_3;
typedef Point_set::Point_map Pmap;
typedef Point_set::Property_map<int> Imap;
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::Sum_of_weighted_features_classifier Classifier;
typedef Classification::Point_set_feature_generator<Kernel, Point_set, Pmap> Feature_generator;
int main (int argc, char** argv)
{
std::string filename (argc > 1 ? argv[1] : "data/b9_training.ply");
std::ifstream in (filename.c_str(), std::ios::binary);
Point_set pts;
std::cerr << "Reading input" << std::endl;
in >> pts;
Imap label_map;
bool lm_found = false;
std::tie (label_map, lm_found) = pts.property_map<int> ("label");
if (!lm_found)
{
std::cerr << "Error: \"label\" property not found in input file." << std::endl;
return EXIT_FAILURE;
}
std::cerr << "Generating features" << std::endl;
CGAL::Real_timer t;
t.start();
Feature_set features;
std::size_t number_of_scales = 5;
Feature_generator generator (pts, pts.point_map(), number_of_scales);
features.begin_parallel_additions();
generator.generate_point_based_features (features);
features.end_parallel_additions();
t.stop();
std::cerr << features.size() << " feature(s) generated in " << t.time() << " second(s)" << std::endl;
Label_set labels = { "ground", "vegetation", "roof" };
Classifier classifier (labels, features);
std::cerr << "Training" << std::endl;
t.reset();
t.start();
classifier.train<CGAL::Parallel_if_available_tag> (pts.range(label_map), 800);
t.stop();
std::cerr << "Done in " << t.time() << " second(s)" << std::endl;
t.reset();
t.start();
std::vector<int> label_indices(pts.size(), -1);
Classification::classify_with_graphcut<CGAL::Parallel_if_available_tag>
(pts, pts.point_map(), labels, classifier,
generator.neighborhood().k_neighbor_query(12),
0.2f, 10, label_indices);
t.stop();
std::cerr << "Classification with graphcut done in " << t.time() << " second(s)" << std::endl;
std::cerr << "Precision, recall, F1 scores and IoU:" << std::endl;
Classification::Evaluation evaluation (labels, pts.range(label_map), label_indices);
for (Label_handle l : labels)
{
std::cerr << " * " << l->name() << ": "
<< evaluation.precision(l) << " ; "
<< evaluation.recall(l) << " ; "
<< evaluation.f1_score(l) << " ; "
<< evaluation.intersection_over_union(l) << std::endl;
}
std::cerr << "Accuracy = " << evaluation.accuracy() << std::endl
<< "Mean F1 score = " << evaluation.mean_f1_score() << std::endl
<< "Mean IoU = " << evaluation.mean_intersection_over_union() << std::endl;
std::ofstream fconfig ("config.xml");
classifier.save_configuration (fconfig);
fconfig.close();
std::cerr << "All done" << std::endl;
return EXIT_SUCCESS;
}