-The Tracker class uses the MTPGraph. From the definition of the
-spatial topology, it builds a graph with one source, one sink, and two
-nodes per location and time. This structure ensures the trajectories
-computed by the tracker to be node-disjoint by forcing the paths
-computed by the MTPGraph to be edge-disjoint.
+The MTPTracker is a wrapper around the MTPGraph class.
+
+From the defined spatial topology and number of time steps, it builds
+a graph with one source, one sink, and two nodes per location and
+time. This structure ensures that the trajectories computed by the
+MTPTracker will be node-disjoint, since the trajectories computed by
+the MTPGraph are edge-disjoint.
+
+The edges from the source or to the sink, or between these pairs of
+nodes, are of length zero, and the edges between the two nodes of such
+a pair have negative lengths, equal to the opposite of the
+corresponding detection scores.
+
+The file mtp_example.cc gives a very simple usage example of the
+MTPTracker class by setting the tracker parameters dynamically, and
+running the tracking.