X-Git-Url: https://fleuret.org/cgi-bin/gitweb/gitweb.cgi?p=mtp.git;a=blobdiff_plain;f=tracker.cc;h=d19093b1860a2bb038ff69492f25196fc20eab8b;hp=0a76e08670966ea7e357b623e62bbc0b6fdb6f2e;hb=ddbc8b15ea4ff788e10cffd2d3977b65462dd1a7;hpb=0f54e5005de0f05d4bc400f23181301eb40f469e

diff --git a/tracker.cc b/tracker.cc
index 0a76e08..d19093b 100644
--- a/tracker.cc
+++ b/tracker.cc
@@ -1,123 +1,344 @@
 
-///////////////////////////////////////////////////////////////////////////
-// This program is free software: you can redistribute it and/or modify  //
-// it under the terms of the version 3 of the GNU General Public License //
-// as published by the Free Software Foundation.                         //
-//                                                                       //
-// This program is distributed in the hope that it will be useful, but   //
-// WITHOUT ANY WARRANTY; without even the implied warranty of            //
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU      //
-// General Public License for more details.                              //
-//                                                                       //
-// You should have received a copy of the GNU General Public License     //
-// along with this program. If not, see <http://www.gnu.org/licenses/>.  //
-//                                                                       //
-// Written by and Copyright (C) Francois Fleuret                         //
-// Contact <francois.fleuret@idiap.ch> for comments & bug reports        //
-///////////////////////////////////////////////////////////////////////////
+/*
+ *  mtp is the ``Multi Tracked Paths'', an implementation of the
+ *  k-shortest paths algorithm for multi-target tracking.
+ *
+ *  Copyright (c) 2012 Idiap Research Institute, http://www.idiap.ch/
+ *  Written by Francois Fleuret <francois.fleuret@idiap.ch>
+ *
+ *  This file is part of mtp.
+ *
+ *  mtp is free software: you can redistribute it and/or modify it
+ *  under the terms of the GNU General Public License version 3 as
+ *  published by the Free Software Foundation.
+ *
+ *  mtp is distributed in the hope that it will be useful, but WITHOUT
+ *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ *  or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
+ *  License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with selector.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
 
 #include "tracker.h"
 
-Tracker::Tracker(int nb_locations, int nb_time_steps) {
+#include <iostream>
+
+using namespace std;
+
+void Tracker::free() {
+  delete[] _edge_lengths;
+  delete _graph;
+  deallocate_array<scalar_t>(detection_scores);
+  deallocate_array<int>(allowed_motion);
+  delete[] exits;
+  delete[] entrances;
+}
+
+void Tracker::allocate(int nb_time_steps, int nb_locations) {
+  free();
+
   _nb_locations = nb_locations;
   _nb_time_steps = nb_time_steps;
-  _detection_score = allocate_array<scalar_t>(nb_locations, nb_time_steps);
-  _allowed_motion = allocate_array<int>(nb_locations, nb_locations);
-  for(int l = 0; l < nb_locations; l++) {
-    for(int m = 0; m < nb_locations; m++) {
-      _allowed_motion[l][m] = 0;
+
+  detection_scores = allocate_array<scalar_t>(_nb_time_steps, _nb_locations);
+  allowed_motion = allocate_array<int>(_nb_locations, _nb_locations);
+
+  entrances = new int[_nb_locations];
+  exits = new int[_nb_locations];
+
+  for(int l = 0; l < _nb_locations; l++) {
+    entrances[l] = 0;
+    exits[l] = 0;
+    for(int m = 0; m < _nb_locations; m++) {
+      allowed_motion[l][m] = 0;
+    }
+  }
+
+  for(int t = 0; t < _nb_time_steps; t++) {
+    for(int l = 0; l < _nb_locations; l++) {
+      detection_scores[t][l] = 0.0;
+    }
+  }
+
+  _edge_lengths = 0;
+  _graph = 0;
+}
+
+void Tracker::write(ostream *os) {
+  (*os) << _nb_locations << " " << _nb_time_steps <<endl;
+
+  (*os) << endl;
+
+  for(int l = 0; l < _nb_locations; l++) {
+    for(int m = 0; m < _nb_locations; m++) {
+      (*os) << allowed_motion[l][m];
+      if(m < _nb_locations - 1) (*os) << " "; else (*os) << endl;
+    }
+  }
+
+  (*os) << endl;
+
+  for(int l = 0; l < _nb_locations; l++) {
+    (*os) << entrances[l];
+    if(l < _nb_locations - 1) (*os) << " "; else (*os) << endl;
+  }
+
+  (*os) << endl;
+
+  for(int l = 0; l < _nb_locations; l++) {
+    (*os) << exits[l];
+    if(l < _nb_locations - 1) (*os) << " "; else (*os) << endl;
+  }
+
+  (*os) << endl;
+
+  for(int t = 0; t < _nb_time_steps; t++) {
+    for(int l = 0; l < _nb_locations; l++) {
+      (*os) << detection_scores[t][l];
+      if(l < _nb_locations - 1) (*os) << " "; else (*os) << endl;
+    }
+  }
+}
+
+void Tracker::read(istream *is) {
+  int nb_locations, nb_time_steps;
+
+  (*is) >> nb_locations >> nb_time_steps;
+
+  allocate(nb_time_steps, nb_locations);
+
+  for(int l = 0; l < _nb_locations; l++) {
+    for(int m = 0; m < _nb_locations; m++) {
+      (*is) >> allowed_motion[l][m];
+    }
+  }
+
+  for(int l = 0; l < _nb_locations; l++) {
+    (*is) >> entrances[l];
+  }
+
+  for(int l = 0; l < _nb_locations; l++) {
+    (*is) >> exits[l];
+  }
+
+  for(int t = 0; t < _nb_time_steps; t++) {
+    for(int l = 0; l < _nb_locations; l++) {
+      (*is) >> detection_scores[t][l];
+    }
+  }
+}
+
+void Tracker::write_trajectories(ostream *os) {
+  for(int t = 0; t < nb_trajectories(); t++) {
+    (*os) << t
+         << " " << trajectory_entrance_time(t)
+         << " " << trajectory_duration(t)
+         << " " << trajectory_score(t);
+    for(int u = 0; u < trajectory_duration(t); u++) {
+      (*os) << " " << trajectory_location(t, u);
     }
+    (*os) << endl;
   }
 }
 
+Tracker::Tracker() {
+  _nb_locations = 0;
+  _nb_time_steps = 0;
+
+  detection_scores = 0;
+  allowed_motion = 0;
+
+  entrances = 0;
+  exits = 0;
+
+  _edge_lengths = 0;
+  _graph = 0;
+}
+
 Tracker::~Tracker() {
+  delete[] _edge_lengths;
+  delete _graph;
+  deallocate_array<scalar_t>(detection_scores);
+  deallocate_array<int>(allowed_motion);
+  delete[] exits;
+  delete[] entrances;
 }
 
-void Tracker::set_allowed_motion(int from_location, int to_location) {
-  _allowed_motion[from_location][to_location] = 1;
+int Tracker::early_pair_node(int t, int l) {
+  return 1 + (2 * (t + 0) + 0) * _nb_locations + l;
 }
 
-void Tracker::set_detection_score(int location, int time, scalar_t score) {
+int Tracker::late_pair_node(int t, int l) {
+  return 1 + (2 * (t + 0) + 1) * _nb_locations + l;
 }
 
-void Tracker::track() {
+void Tracker::build_graph() {
+  // Delete the existing graph if there was one
+  delete[] _edge_lengths;
+  delete _graph;
 
-  cout << "Building graph." << endl;
+  int nb_motions = 0, nb_exits = 0, nb_entrances = 0;
 
-  int nb_motions = 0;
   for(int l = 0; l < _nb_locations; l++) {
+    if(exits[l]) nb_exits++;
+    if(entrances[l]) nb_entrances++;
     for(int m = 0; m < _nb_locations; m++) {
-      if(_allowed_motion[l][m]) nb_motions++;
+      if(allowed_motion[l][m]) nb_motions++;
     }
   }
 
-  int nb_vertices = 2 + 2 * (_nb_time_steps + 1) * _nb_locations;
-  int nb_edges = _nb_locations * 2    // From source and to sink
-    + _nb_time_steps * nb_motions     // Motions
-    + _nb_locations * _nb_time_steps; // Doubling of nodes to force
-                                      // one target per location
+  int nb_vertices = 2 + 2 * _nb_time_steps * _nb_locations;
+
+  int nb_edges =
+    // The edges from the source to the first frame, and from the last
+    // frame to the sink
+    _nb_locations * 2 +
+    // The edges from the source to the entrances and from the exits
+    // to the sink (in every time frames but the first for the
+    // entrances, and last for the exits)
+    (_nb_time_steps - 1) * (nb_exits + nb_entrances) +
+    // The edges for the motions, between every successive frames
+    (_nb_time_steps - 1) * nb_motions +
+    // The edges inside the duplicated nodes
+    _nb_locations * _nb_time_steps;
 
-  int source = 0, sink = nb_vertices - 1;
   int *node_from = new int[nb_edges];
   int *node_to = new int[nb_edges];
-  scalar_t *edge_length = new scalar_t[nb_edges];
+
+  int source = 0, sink = nb_vertices - 1;
   int e = 0;
 
+  _edge_lengths = new scalar_t[nb_edges];
+
+  // We put the in-node edges first, since these are the ones whose
+  // lengths we will have to change before tracking, according to the
+  // detection scores
+
+  for(int t = 0; t < _nb_time_steps; t++) {
+    for(int l = 0; l < _nb_locations; l++) {
+      node_from[e] = early_pair_node(t, l);
+      node_to[e] = late_pair_node(t, l);
+      e++;
+    }
+  }
+
+  // The edges from the source to the first time frame
+
   for(int l = 0; l < _nb_locations; l++) {
     node_from[e] = source;
     node_to[e] = 1 + l + 0 * _nb_locations;
-    edge_length[e] = 0.0;
+    _edge_lengths[e] = 0.0;
+    e++;
+  }
+
+  // The edges from the last frame to the sink
+
+  for(int l = 0; l < _nb_locations; l++) {
+    node_from[e] = late_pair_node(_nb_time_steps - 1, l);
+    node_to[e] = sink;
+    _edge_lengths[e] = 0.0;
     e++;
   }
 
-  for(int t = 0; t <= _nb_time_steps; t++) {
+  // The edges between frames, corresponding to allowed motions
+
+  for(int t = 0; t < _nb_time_steps - 1; t++) {
     for(int l = 0; l < _nb_locations; l++) {
-      node_from[e] = 1 + (2 * (t + 0) + 0) * _nb_locations + l;
-      node_to[e] =   1 + (2 * (t + 0) + 1) * _nb_locations + l;
-      edge_length[e] = _detection_score[t][l];
-      e++;
-      if(t == _nb_time_steps) {
-        node_from[e] = 1 + (2 * (t + 0) + 0) * _nb_locations + l;
-        node_to[e] =   sink;
-        edge_length[e] = 0;
-        e++;
-      } else {
-        for(int k = 0; k < _nb_locations; k++) {
-          if(_allowed_motion[l][k]) {
-            node_from[e] = 1 + (2 * (t + 0) + 1) * _nb_locations + l;
-            node_to[e] =   1 + (2 * (t + 1) + 0) * _nb_locations + k;
-            edge_length[e] = 0.0;
-            e++;
-          }
+      for(int k = 0; k < _nb_locations; k++) {
+        if(allowed_motion[l][k]) {
+          node_from[e] = late_pair_node(t, l);
+          node_to[e] = early_pair_node(t+1, k);
+          _edge_lengths[e] = 0.0;
+          e++;
         }
       }
     }
   }
+
+  // The edges from the source to the entrances, and from the exits to
+  // the sink
+
+  for(int t = 0; t < _nb_time_steps; t++) {
+    for(int l = 0; l < _nb_locations; l++) {
+      if(t > 0 && entrances[l]) {
+        node_from[e] = source;
+        node_to[e] = early_pair_node(t, l);
+        _edge_lengths[e] = 0.0;
+        e++;
+      }
+      if(t < _nb_time_steps - 1 && exits[l]) {
+        node_from[e] = late_pair_node(t, l);
+        node_to[e] = sink;
+        _edge_lengths[e] = 0.0;
+        e++;
+      }
+    }
+  }
+
+  // We are done, build the graph
+
+  _graph = new MTPGraph(nb_vertices, nb_edges,
+                        node_from, node_to,
+                        source, sink);
+
+  delete[] node_from;
+  delete[] node_to;
 }
 
-// void Tracker::track() {
-  // int e = _nb_locations;
-  // for(int t = 0; t <= _nb_time_steps; t++) {
-    // for(int l = 0; l < _nb_locations; l++) {
-      // edge_length[e] = _detection_score[t][l];
-      // e++;
-      // if(t == _nb_time_steps) {
-        // e++;
-      // } else {
-        // e += _nb_locations;
-      // }
-    // }
-  // }
-// }
+void Tracker::print_graph_dot(ostream *os) {
+  int e = 0;
+  for(int t = 0; t < _nb_time_steps; t++) {
+    for(int l = 0; l < _nb_locations; l++) {
+      _edge_lengths[e++] = - detection_scores[t][l];
+    }
+  }
+  _graph->print_dot(os);
+}
+
+void Tracker::track() {
+  ASSERT(_graph);
+
+  int e = 0;
+  for(int t = 0; t < _nb_time_steps; t++) {
+    for(int l = 0; l < _nb_locations; l++) {
+      _edge_lengths[e++] = - detection_scores[t][l];
+    }
+  }
+
+  _graph->find_best_paths(_edge_lengths);
+  _graph->retrieve_disjoint_paths();
+
+#ifdef VERBOSE
+  for(int p = 0; p < _graph->nb_paths; p++) {
+    Path *path = _graph->paths[p];
+    cout << "PATH " << p << " [length " << path->nb_nodes << "] " << path->nodes[0];
+    for(int n = 1; n < path->nb_nodes; n++) {
+      cout << " -> " << path->nodes[n];
+    }
+    cout << endl;
+  }
+#endif
+}
 
 int Tracker::nb_trajectories() {
+  return _graph->nb_paths;
+}
+
+scalar_t Tracker::trajectory_score(int k) {
+  return -_graph->paths[k]->length;
 }
 
-int Tracker::trajectory_start_time(int k) {
+int Tracker::trajectory_entrance_time(int k) {
+  return (_graph->paths[k]->nodes[1] - 1) / (2 * _nb_locations);
 }
 
-int Tracker::trajectory_end_time(int k) {
+int Tracker::trajectory_duration(int k) {
+  return (_graph->paths[k]->nb_nodes - 2) / 2;
 }
 
-int Tracker::trajectory_location(int k, int time) {
+int Tracker::trajectory_location(int k, int time_from_entry) {
+  return (_graph->paths[k]->nodes[2 * time_from_entry + 1] - 1) % _nb_locations;
 }