From e30bef5dcdf0e788cb2cf89240ec78871afe71f7 Mon Sep 17 00:00:00 2001
From: Mykhailo Bilyi <misha.beliy15@gmail.com>
Date: Thu, 7 Sep 2023 13:36:10 +0200
Subject: [PATCH] Add Match method for BFMatcher

---
 features2d.cpp     | 13 +++++++++++++
 features2d.go      | 12 ++++++++++++
 features2d.h       |  1 +
 features2d_test.go |  5 +++++
 4 files changed, 31 insertions(+)

diff --git a/features2d.cpp b/features2d.cpp
index f7b18e30..0ccce5f8 100644
--- a/features2d.cpp
+++ b/features2d.cpp
@@ -380,6 +380,19 @@ void BFMatcher_Close(BFMatcher b) {
     delete b;
 }
 
+struct DMatches BFMatcher_Match(BFMatcher b, Mat query, Mat train) {
+    std::vector<cv::DMatch> matches;
+    (*b)->match(*query, *train, matches);
+
+    DMatch *dmatches = new DMatch[matches.size()];
+    for (size_t i = 0; i < matches.size(); ++i) {
+        DMatch dmatch = {matches[i].queryIdx, matches[i].trainIdx, matches[i].imgIdx, matches[i].distance};
+        dmatches[i] = dmatch;
+    }
+    DMatches ret = {dmatches, (int) matches.size()};
+    return ret;
+}
+
 struct MultiDMatches BFMatcher_KnnMatch(BFMatcher b, Mat query, Mat train, int k) {
     std::vector< std::vector<cv::DMatch> > matches;
     (*b)->knnMatch(*query, *train, matches, k);
diff --git a/features2d.go b/features2d.go
index 162b604f..4a0fffd7 100644
--- a/features2d.go
+++ b/features2d.go
@@ -679,6 +679,18 @@ func (b *BFMatcher) Close() error {
 	return nil
 }
 
+// Match Finds the best match for each descriptor from a query set.
+//
+// For further details, please see:
+// https://docs.opencv.org/4.x/db/d39/classcv_1_1DescriptorMatcher.html#a0f046f47b68ec7074391e1e85c750cba
+//
+func (b *BFMatcher) Match(query, train Mat) []DMatch {
+	ret := C.BFMatcher_Match((C.BFMatcher)(b.p), query.p, train.p)
+	defer C.DMatches_Close(ret)
+
+	return getDMatches(ret)
+}
+
 // KnnMatch Finds the k best matches for each descriptor from a query set.
 //
 // For further details, please see:
diff --git a/features2d.h b/features2d.h
index b6a9c4fc..4042a0e3 100644
--- a/features2d.h
+++ b/features2d.h
@@ -83,6 +83,7 @@ SimpleBlobDetectorParams SimpleBlobDetectorParams_Create();
 BFMatcher BFMatcher_Create();
 BFMatcher BFMatcher_CreateWithParams(int normType, bool crossCheck);
 void BFMatcher_Close(BFMatcher b);
+struct DMatches BFMatcher_Match(BFMatcher b, Mat query, Mat train);
 struct MultiDMatches BFMatcher_KnnMatch(BFMatcher b, Mat query, Mat train, int k);
 
 FlannBasedMatcher FlannBasedMatcher_Create();
diff --git a/features2d_test.go b/features2d_test.go
index bc16ed25..cc8e8d69 100644
--- a/features2d_test.go
+++ b/features2d_test.go
@@ -420,6 +420,11 @@ func TestBFMatcher(t *testing.T) {
 		}
 	}
 
+	matches := bf.Match(desc1, desc2)
+	if len(matches) != 890 {
+		t.Errorf("Matches was excepted to have 890 elements, but it has %d", len(matches))
+	}
+
 	bfParams := NewBFMatcherWithParams(NormHamming, false)
 	defer bfParams.Close()