// Multi-Tracked Path
-// Takes the graph description file as input and produces a dot file.
-
-// EXAMPLE: ./mtp ./graph2.txt | dot -T pdf -o- | xpdf -
-
-#define VERBOSE
-
#include <iostream>
#include <fstream>
-#include <cmath>
-#include <stdio.h>
-#include <stdlib.h>
-#include <float.h>
using namespace std;
-typedef float scalar_t;
-
-#ifdef DEBUG
-#define ASSERT(x) if(!(x)) { \
- std::cerr << "ASSERT FAILED IN " << __FILE__ << ":" << __LINE__ << endl; \
- abort(); \
-}
-#else
-#define ASSERT(x)
-#endif
-
-class Vertex;
-
-class Edge {
-public:
- int id, occupied;
- scalar_t length, work_length;
- Vertex *terminal_vertex;
- Edge *next, *pred;
-};
-
-class Vertex {
-public:
- int id, iteration;
- Edge *root_edge;
- scalar_t distance_from_source;
- Vertex *pred_vertex;
- Edge *pred_edge;
-
- Vertex() { root_edge = 0; }
-
- inline void add_edge(Edge *e) {
- e->next = root_edge;
- e->pred = 0;
- if(root_edge) { root_edge->pred = e; }
- root_edge = e;
- }
-
- inline void del_edge(Edge *e) {
- if(e == root_edge) { root_edge = e->next; }
- if(e->pred) { e->pred->next = e->next; }
- if(e->next) { e->next->pred = e->pred; }
- }
-};
-
-class Graph {
- void initialize_work_lengths();
- void update_work_length();
- void find_shortest_path(Vertex **front, Vertex **new_front);
-
- int nb_vertices;
- Edge *edge_heap;
- Vertex *vertices;
- Vertex *source, *sink;
-public:
- Graph(int nb_vertices, int nb_edges, int *from, int *to, scalar_t *lengths,
- int source, int sink);
+#include "tracker.h"
- ~Graph();
-
- void find_best_paths(int *result_edge_occupation);
- void print();
-};
-
-void Graph::print() {
- for(int n = 0; n < nb_vertices; n++) {
- for(Edge *e = vertices[n].root_edge; e; e = e->next) {
- cout << n << " -> " << e->terminal_vertex->id << " " << e->length;
- if(e->occupied) {
- cout << " *";
- }
- cout << endl;
- }
- }
-}
-
-Graph::Graph(int nb_vrt, int nb_edges,
- int *from, int *to, scalar_t *lengths,
- int src, int snk) {
- nb_vertices = nb_vrt;
-
- edge_heap = new Edge[nb_edges];
- vertices = new Vertex[nb_vertices];
-
- source = &vertices[src];
- sink = &vertices[snk];
-
- for(int v = 0; v < nb_vertices; v++) {
- vertices[v].id = v;
- }
+//////////////////////////////////////////////////////////////////////
- for(int e = 0; e < nb_edges; e++) {
- vertices[from[e]].add_edge(&edge_heap[e]);
- edge_heap[e].occupied = 0;
- edge_heap[e].id = e;
- edge_heap[e].length = lengths[e];
- edge_heap[e].terminal_vertex = &vertices[to[e]];
+scalar_t detection_score(int true_label, scalar_t flip_noise) {
+ if((true_label > 0) == (drand48() < flip_noise)) {
+ return 1.0 + 0.2 * (drand48() - 0.5);
+ } else {
+ return - 1.0 + 0.2 * (drand48() - 0.5);
}
}
-Graph::~Graph() {
- delete[] vertices;
- delete[] edge_heap;
-}
+int main(int argc, char **argv) {
+ int nb_locations = 6;
+ int nb_time_steps = 5;
+ int motion_amplitude = 1;
-void Graph::initialize_work_lengths() {
- scalar_t length_min = 0;
- for(int n = 0; n < nb_vertices; n++) {
- for(Edge *e = vertices[n].root_edge; e; e = e->next) {
- length_min = min(e->length, length_min);
- }
- }
- for(int n = 0; n < nb_vertices; n++) {
- for(Edge *e = vertices[n].root_edge; e; e = e->next) {
- e->work_length = e->length - length_min;
- }
- }
-}
+ Tracker *tracker = new Tracker(nb_time_steps, nb_locations);
-void Graph::update_work_length() {
- for(int n = 0; n < nb_vertices; n++) {
- scalar_t d = vertices[n].distance_from_source;
- for(Edge *e = vertices[n].root_edge; e; e = e->next) {
- e->work_length += d - e->terminal_vertex->distance_from_source;
+ for(int l = 0; l < nb_locations; l++) {
+ for(int k = 0; k < nb_locations; k++) {
+ tracker->allowed_motion[l][k] = abs(l - k) <= motion_amplitude;
}
+ tracker->entrances[0] = 1;
+ tracker->exits[nb_locations - 1] = 1;
}
-}
-void Graph::find_shortest_path(Vertex **front, Vertex **new_front) {
- Vertex **tmp_front;
- int tmp_front_size;
- Vertex *v, *tv;
- scalar_t d;
+ tracker->build_graph();
-#ifdef VERBOSE
- cout << "find_shortest_path" << endl;
-#endif
+ // We generate synthetic detection scores at location
+ // nb_locations/2, with 5% false detection (FP or FN)
-#ifdef DEBUG
- scalar_t residual_error = 0.0;
-#endif
- for(int n = 0; n < nb_vertices; n++) {
- for(Edge *e = vertices[n].root_edge; e; e = e->next) {
- if(e->work_length < 0) {
-#ifdef DEBUG
- residual_error -= e->work_length;
-#endif
- e->work_length = 0.0;
- }
+ for(int t = 0; t < nb_time_steps; t++) {
+ for(int l = 0; l < nb_locations; l++) {
+ tracker->detection_score[t][l] = detection_score(-1, 0.95);
}
}
-#ifdef DEBUG
- cout << "DEBUG residual_error " << residual_error << endl;
-#endif
- for(int v = 0; v < nb_vertices; v++) {
- vertices[v].distance_from_source = FLT_MAX;
- vertices[v].pred_vertex = 0;
- vertices[v].pred_edge = 0;
- vertices[v].iteration = 0;
+ for(int t = 0; t < nb_time_steps; t++) {
+ tracker->detection_score[t][nb_locations/2] = detection_score(1, 0.95);
}
- int iteration = 0;
-
- int front_size = 0, new_front_size;
- front[front_size++] = source;
- source->distance_from_source = 0;
-
- do {
- new_front_size = 0;
- iteration++;
- for(int f = 0; f < front_size; f++) {
- v = front[f];
- for(Edge *e = v->root_edge; e; e = e->next) {
- d = v->distance_from_source + e->work_length;
- tv = e->terminal_vertex;
- if(d < tv->distance_from_source) {
- tv->distance_from_source = d;
- tv->pred_vertex = v;
- tv->pred_edge = e;
- if(tv->iteration < iteration) {
- new_front[new_front_size++] = tv;
- tv->iteration = iteration;
- }
- }
- }
- }
-
- tmp_front = new_front;
- new_front = front;
- front = tmp_front;
-
- tmp_front_size = new_front_size;
- new_front_size = front_size;
- front_size = tmp_front_size;
- } while(front_size > 0);
-}
-
-void Graph::find_best_paths(int *result_edge_occupation) {
- Vertex **front = new Vertex *[nb_vertices];
- Vertex **new_front = new Vertex *[nb_vertices];
-
- scalar_t total_length;
-
- initialize_work_lengths();
-
- do {
- total_length = 0.0;
- find_shortest_path(front, new_front);
- update_work_length();
-
- // Do we reach the sink?
- if(sink->pred_edge) {
-
- // If yes, compute the length of the best path
- for(Vertex *v = sink; v->pred_edge; v = v->pred_vertex) {
- total_length += v->pred_edge->length;
- }
-
- // If that length is negative
- if(total_length < 0.0) {
- // Invert all the edges along the best path
- for(Vertex *v = sink; v->pred_edge; v = v->pred_vertex) {
- Edge *e = v->pred_edge;
- e->terminal_vertex = v->pred_vertex;
- e->occupied = 1 - e->occupied;
- e->length = - e->length;
- e->work_length = - e->work_length;
- v->pred_vertex->del_edge(e);
- v->add_edge(e);
- }
- }
- }
- } while(total_length < 0.0);
-
- delete[] front;
- delete[] new_front;
-
- for(int n = 0; n < nb_vertices; n++) {
- Vertex *v = &vertices[n];
- for(Edge *e = v->root_edge; e; e = e->next) {
- result_edge_occupation[e->id] = e->occupied;
+ // Puts two target with the typical local minimum (i.e. the optimal
+ // single path would track the first target on the first half and
+ // the second on the second half, while the optimal two paths would
+ // each follow one of the target properly)
+
+ // for(int t = 0; t < nb_time_steps; t++) {
+ // int a = nb_time_steps/2 - abs(t - nb_time_steps/2);
+ // int b = nb_locations - 1 - a;
+ // if(a > nb_locations/2 - 1) a = nb_locations/2 - 1;
+ // if(b < nb_locations/2 + 1) b = nb_locations/2 + 1;
+ // if(t < nb_time_steps/2) {
+ // tracker->detection_score[t][a] = 10.0;
+ // tracker->detection_score[t][b] = 1.0;
+ // } else {
+ // tracker->detection_score[t][a] = 1.0;
+ // tracker->detection_score[t][b] = 10.0;
+ // }
+ // }
+
+ tracker->track();
+
+ for(int t = 0; t < tracker->nb_trajectories(); t++) {
+ cout << "TRAJECTORY "
+ << t
+ << " [starting " << tracker->trajectory_entrance_time(t)
+ << ", score " << tracker->trajectory_score(t) << "]";
+ for(int u = 0; u < tracker->trajectory_duration(t); u++) {
+ cout << " " << tracker->trajectory_location(t, u);
}
+ cout << endl;
}
-}
-
-void find_best_paths(int nb_vertices,
- int nb_edges, int *ea, int *eb, scalar_t *el,
- int source, int sink,
- int *result_edge_occupation) {
- Graph graph(nb_vertices, nb_edges, ea, eb, el, source, sink);
- graph.find_best_paths(result_edge_occupation);
-}
-
-void dot_print(int nb_vertices,
- int nb_edges, int *ea, int *eb, scalar_t *el,
- int source, int sink,
- int *edge_occupation) {
- cout << "digraph {" << endl;
- cout << " node[shape=circle];" << endl;
- for(int e = 0; e < nb_edges; e++) {
- if(edge_occupation[e]) {
- cout << " " << ea[e] << " -> " << eb[e] << " [style=bold,color=black,label=\"" << el[e] << "\"];" << endl;
- } else {
- cout << " " << ea[e] << " -> " << eb[e] << " [color=gray,label=\"" << el[e] << "\"];" << endl;
- }
- }
- cout << "}" << endl;
-}
-//////////////////////////////////////////////////////////////////////
-
-int main(int argc, char **argv) {
-
- if(argc < 2) {
- cerr << argv[0] << " <graph file>" << endl;
- exit(EXIT_FAILURE);
+ {
+ ofstream dot("graph.dot");
+ tracker->print_graph_dot(&dot);
+ cout << "Wrote graph.dot." << endl;
}
- ifstream *file = new ifstream(argv[1]);
-
- int nb_edges, nb_vertices;
- int source, sink;
-
- if(file->good()) {
-
- (*file) >> nb_vertices >> nb_edges;
- (*file) >> source >> sink;
-
- scalar_t *edge_lengths = new scalar_t[nb_edges];
- int *vertex_from = new int[nb_edges];
- int *vertex_to = new int[nb_edges];
- int *result_edge_occupation = new int[nb_edges];
-
- for(int e = 0; e < nb_edges; e++) {
- (*file) >> vertex_from[e] >> vertex_to[e] >> edge_lengths[e];
- }
-
- find_best_paths(nb_vertices, nb_edges,
- vertex_from, vertex_to, edge_lengths,
- source, sink,
- result_edge_occupation);
-
- // dot_print(nb_vertices, nb_edges,
- // vertex_from, vertex_to, edge_lengths,
- // source, sink,
- // result_edge_occupation);
-
- delete[] result_edge_occupation;
- delete[] edge_lengths;
- delete[] vertex_from;
- delete[] vertex_to;
-
- } else {
-
- cerr << "Can not open " << argv[1] << endl;
-
- delete file;
- exit(EXIT_FAILURE);
-
- }
+ delete tracker;
- delete file;
exit(EXIT_SUCCESS);
}