Added test for checkMasks with UMat train descs

modules/features2d/test/test_matchers_algorithmic.cpp

@@ -565,7 +565,6 @@ TEST(Features2d_DMatch, issue_11855)
                                         1, 1, 1);
     Mat targets = (Mat_<uchar>(2, 3) << 1, 1, 1,
                                         0, 0, 0);
-
     Ptr<BFMatcher> bf = BFMatcher::create(NORM_HAMMING, true);
     vector<vector<DMatch> > match;
     bf->knnMatch(sources, targets, match, 1, noArray(), true);
@@ -577,4 +576,18 @@ TEST(Features2d_DMatch, issue_11855)
     EXPECT_EQ(0.0f, match[0][0].distance);
 }
 
+TEST(Features2d_DMatch, issue_17771)
+{
+    Mat sources = (Mat_<uchar>(2, 3) << 1, 1, 0,
+                                        1, 1, 1);
+    Mat targets = (Mat_<uchar>(2, 3) << 1, 1, 1,
+                                        0, 0, 0);
+    UMat usources = sources.getUMat(ACCESS_READ);
+    UMat utargets = targets.getUMat(ACCESS_READ);
+    vector<vector<DMatch> > match;
+    Ptr<BFMatcher> ubf = BFMatcher::create(NORM_HAMMING);
+    Mat mask = (Mat_<uchar>(2, 2) << 1, 0, 0, 1);
+    EXPECT_NO_THROW(ubf->knnMatch(usources, utargets, match, 1, mask, true));
+}
+
 }} // namespace