Merge remote-tracking branch 'upstream/3.4' into merge-3.4

modules/features2d/test/test_blobdetector.cpp

@@ -0,0 +1,21 @@
+// This file is part of OpenCV project.
+// It is subject to the license terms in the LICENSE file found in the top-level directory
+// of this distribution and at http://opencv.org/license.html.
+
+#include "test_precomp.hpp"
+
+namespace opencv_test { namespace {
+TEST(Features2d_BlobDetector, bug_6667)
+{
+    cv::Mat image = cv::Mat(cv::Size(100, 100), CV_8UC1, cv::Scalar(255, 255, 255));
+    cv::circle(image, Point(50, 50), 20, cv::Scalar(0), -1);
+    SimpleBlobDetector::Params params;
+    params.minThreshold = 250;
+    params.maxThreshold = 260;
+    std::vector<KeyPoint> keypoints;
+
+    Ptr<SimpleBlobDetector> detector = SimpleBlobDetector::create(params);
+    detector->detect(image, keypoints);
+    ASSERT_NE((int) keypoints.size(), 0);
+}
+}} // namespace