From 75374e108145c889c99c2e8061643a71b6a63032 Mon Sep 17 00:00:00 2001
From: Monika Kairaityte <monika@kibit.lt>
Date: Mon, 8 Aug 2022 13:59:47 +0300
Subject: [PATCH] [featureMatching] Extract filterMatchesByMin2DMotion()

---
 src/aliceVision/matching/matchesFiltering.cpp | 49 +++++++++++++++++++
 src/aliceVision/matching/matchesFiltering.hpp |  5 ++
 .../pipeline/main_featureMatching.cpp         | 45 +----------------
 3 files changed, 55 insertions(+), 44 deletions(-)

diff --git a/src/aliceVision/matching/matchesFiltering.cpp b/src/aliceVision/matching/matchesFiltering.cpp
index cb1d17aeed..f550002668 100644
--- a/src/aliceVision/matching/matchesFiltering.cpp
+++ b/src/aliceVision/matching/matchesFiltering.cpp
@@ -139,5 +139,54 @@ void matchesGridFiltering(const aliceVision::feature::Regions& lRegions,
     outMatches.swap(finalMatches);
 }
 
+void filterMatchesByMin2DMotion(PairwiseMatches& mapPutativesMatches,
+                                const feature::RegionsPerView& regionPerView,
+                                double minRequired2DMotion)
+{
+    if (minRequired2DMotion < 0.0f)
+        return;
+
+    //For each image pair
+    for (auto& imgPair: mapPutativesMatches)
+    {
+        const Pair viewPair = imgPair.first;
+        IndexT viewI = viewPair.first;
+        IndexT viewJ = viewPair.second;
+
+        //For each descriptors in this image
+        for (auto& descType: imgPair.second)
+        {
+            const feature::EImageDescriberType type = descType.first;
+
+            const feature::Regions & regions_I = regionPerView.getRegions(viewI, type);
+            const feature::Regions & regions_J = regionPerView.getRegions(viewJ, type);
+
+            const auto & features_I = regions_I.Features();
+            const auto & features_J = regions_J.Features();
+
+            IndMatches & matches = descType.second;
+            IndMatches updated_matches;
+
+            for (auto & match : matches)
+            {
+                Vec2f pi = features_I[match._i].coords();
+                Vec2f pj = features_J[match._j].coords();
+
+                float scale = std::max(features_I[match._i].scale(), features_J[match._j].scale());
+                float coeff = pow(2, scale);
+
+                if ((pi - pj).norm() < (minRequired2DMotion * coeff))
+                {
+                    continue;
+                }
+
+                updated_matches.push_back(match);
+            }
+
+            matches = updated_matches;
+        }
+    }
+}
+
 } // namespace sfm
 } // namespace aliceVision
diff --git a/src/aliceVision/matching/matchesFiltering.hpp b/src/aliceVision/matching/matchesFiltering.hpp
index 9c9e593fba..2898167bc9 100644
--- a/src/aliceVision/matching/matchesFiltering.hpp
+++ b/src/aliceVision/matching/matchesFiltering.hpp
@@ -8,6 +8,7 @@
 
 #include <aliceVision/sfmData/SfMData.hpp>
 #include <aliceVision/feature/Regions.hpp>
+#include <aliceVision/feature/RegionsPerView.hpp>
 #include <aliceVision/feature/feature.hpp>
 #include <aliceVision/matching/IndMatch.hpp>
 
@@ -66,5 +67,9 @@ void matchesGridFiltering(const aliceVision::feature::Regions& lRegions,
                           const aliceVision::Pair& indexImagePair,
                           aliceVision::matching::IndMatches& outMatches, size_t gridSize = 3);
 
+void filterMatchesByMin2DMotion(PairwiseMatches& mapPutativesMatches,
+                                const feature::RegionsPerView& regionPerView,
+                                double minRequired2DMotion);
+
 } // namespace sfm
 } // namespace aliceVision
diff --git a/src/software/pipeline/main_featureMatching.cpp b/src/software/pipeline/main_featureMatching.cpp
index 375f513079..ff97d32acd 100644
--- a/src/software/pipeline/main_featureMatching.cpp
+++ b/src/software/pipeline/main_featureMatching.cpp
@@ -383,50 +383,7 @@ int aliceVision_main(int argc, char **argv)
 
   }
 
-  if (minRequired2DMotion >= 0.0f)
-  {
-    //For each image pair
-    for (auto& imgPair: mapPutativesMatches)
-    {
-      const Pair viewPair = imgPair.first;
-      IndexT viewI = viewPair.first;
-      IndexT viewJ = viewPair.second;
-
-      //For each descriptors in this image
-      for (auto& descType: imgPair.second)
-      {
-        const feature::EImageDescriberType type = descType.first;
-
-        const feature::Regions & regions_I = regionPerView.getRegions(viewI, type);
-        const feature::Regions & regions_J = regionPerView.getRegions(viewJ, type);
-
-        const auto & features_I = regions_I.Features();        
-        const auto & features_J = regions_J.Features();        
-        
-        IndMatches & matches = descType.second;
-        IndMatches updated_matches;
-
-        for (auto & match : matches)
-        {
-          
-          Vec2f pi = features_I[match._i].coords();
-          Vec2f pj = features_J[match._j].coords();
-
-          float scale = std::max(features_I[match._i].scale(), features_J[match._j].scale());
-          float coeff = pow(2, scale);
-
-          if ((pi - pj).norm() < (minRequired2DMotion * coeff))
-          {
-            continue;
-          }
-
-          updated_matches.push_back(match);
-        }
-
-        matches = updated_matches;
-      }
-    }
-  }
+  filterMatchesByMin2DMotion(mapPutativesMatches, regionPerView, minRequired2DMotion);
 
   if(mapPutativesMatches.empty())
   {