From a372ade7ce145f35f16989e59ce71bcc874975a8 Mon Sep 17 00:00:00 2001
From: Patrick Niklaus <patrick.niklaus@student.kit.edu>
Date: Tue, 17 Mar 2015 01:00:04 +0100
Subject: [PATCH] Mark suspicious transitions

---
 data_structures/hidden_markov_model.hpp | 4 ++++
 routing_algorithms/map_matching.hpp     | 9 +++++++--
 util/matching_debug_info.hpp            | 5 ++++-
 3 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/data_structures/hidden_markov_model.hpp b/data_structures/hidden_markov_model.hpp
index 403f76608..cccaf7b5d 100644
--- a/data_structures/hidden_markov_model.hpp
+++ b/data_structures/hidden_markov_model.hpp
@@ -80,6 +80,7 @@ template <class CandidateLists> struct HiddenMarkovModel
     std::vector<std::vector<std::pair<unsigned, unsigned>>> parents;
     std::vector<std::vector<float>> path_lengths;
     std::vector<std::vector<bool>> pruned;
+    std::vector<std::vector<bool>> suspicious;
     std::vector<bool> breakage;
 
     const CandidateLists &candidates_list;
@@ -95,6 +96,7 @@ template <class CandidateLists> struct HiddenMarkovModel
             viterbi.emplace_back(l.size());
             parents.emplace_back(l.size());
             path_lengths.emplace_back(l.size());
+            suspicious.emplace_back(l.size());
             pruned.emplace_back(l.size());
         }
 
@@ -111,6 +113,7 @@ template <class CandidateLists> struct HiddenMarkovModel
             std::fill(viterbi[t].begin(), viterbi[t].end(), osrm::matching::IMPOSSIBLE_LOG_PROB);
             std::fill(parents[t].begin(), parents[t].end(), std::make_pair(0u, 0u));
             std::fill(path_lengths[t].begin(), path_lengths[t].end(), 0);
+            std::fill(suspicious[t].begin(), suspicious[t].end(), true);
             std::fill(pruned[t].begin(), pruned[t].end(), true);
         }
         std::fill(breakage.begin() + initial_timestamp, breakage.end(), true);
@@ -129,6 +132,7 @@ template <class CandidateLists> struct HiddenMarkovModel
                 parents[initial_timestamp][s] = std::make_pair(initial_timestamp, s);
                 pruned[initial_timestamp][s] =
                     viterbi[initial_timestamp][s] < osrm::matching::MINIMAL_LOG_PROB;
+                suspicious[initial_timestamp][s] = false;
 
                 breakage[initial_timestamp] =
                     breakage[initial_timestamp] && pruned[initial_timestamp][s];
diff --git a/routing_algorithms/map_matching.hpp b/routing_algorithms/map_matching.hpp
index 75598ca2c..eb405a8e4 100644
--- a/routing_algorithms/map_matching.hpp
+++ b/routing_algorithms/map_matching.hpp
@@ -62,6 +62,9 @@ using SubMatchingList = std::vector<SubMatching>;
 constexpr static const unsigned MAX_BROKEN_STATES = 6;
 constexpr static const unsigned MAX_BROKEN_TIME = 60;
 
+constexpr static const unsigned MAX_DISTANCE_DELTA = 500;
+constexpr static const unsigned SUSPICIOUS_DISTANCE_DELTA = 100;
+
 constexpr static const double default_beta = 10.0;
 constexpr static const double default_sigma_z = 4.07;
 }
@@ -168,6 +171,7 @@ class MapMatching final : public BasicRoutingInterface<DataFacadeT, MapMatching<
 
             auto &current_viterbi = model.viterbi[t];
             auto &current_pruned = model.pruned[t];
+            auto &current_suspicious = model.suspicious[t];
             auto &current_parents = model.parents[t];
             auto &current_lengths = model.path_lengths[t];
             const auto &current_timestamps_list = candidates_list[t];
@@ -214,7 +218,7 @@ class MapMatching final : public BasicRoutingInterface<DataFacadeT, MapMatching<
                     const auto d_t = std::abs(network_distance - great_circle_distance);
 
                     // very low probability transition -> prune
-                    if (d_t > 500)
+                    if (d_t > osrm::matching::MAX_DISTANCE_DELTA)
                     {
                         continue;
                     }
@@ -232,6 +236,7 @@ class MapMatching final : public BasicRoutingInterface<DataFacadeT, MapMatching<
                         current_parents[s_prime] = std::make_pair(prev_unbroken_timestamp, s);
                         current_lengths[s_prime] = network_distance;
                         current_pruned[s_prime] = false;
+                        current_suspicious[s_prime] = d_t > osrm::matching::SUSPICIOUS_DISTANCE_DELTA;
                         model.breakage[t] = false;
                     }
                 }
@@ -255,7 +260,7 @@ class MapMatching final : public BasicRoutingInterface<DataFacadeT, MapMatching<
             }
         }
 
-        matching_debug.set_viterbi(model.viterbi, model.pruned);
+        matching_debug.set_viterbi(model.viterbi, model.pruned, model.suspicious);
 
         if (!prev_unbroken_timestamps.empty())
         {
diff --git a/util/matching_debug_info.hpp b/util/matching_debug_info.hpp
index 284bd9f57..faf878e3f 100644
--- a/util/matching_debug_info.hpp
+++ b/util/matching_debug_info.hpp
@@ -103,7 +103,8 @@ struct MatchingDebugInfo
     }
 
     void set_viterbi(const std::vector<std::vector<double>> &viterbi,
-                     const std::vector<std::vector<bool>> &pruned)
+                     const std::vector<std::vector<bool>> &pruned,
+                     const std::vector<std::vector<bool>> &suspicious)
     {
         // json logger not enabled
         if (!logger)
@@ -119,6 +120,8 @@ struct MatchingDebugInfo
                     osrm::json::clamp_float(viterbi[t][s_prime]);
                 osrm::json::get(*object, "states", t, s_prime, "pruned") =
                     static_cast<unsigned>(pruned[t][s_prime]);
+                osrm::json::get(*object, "states", t, s_prime, "suspicious") =
+                    static_cast<unsigned>(suspicious[t][s_prime]);
             }
         }
     }