dnn: add an accuracy test for NMS

modules/dnn/src/layers/detection_output_layer.cpp

@@ -45,7 +45,7 @@
 #include <float.h>
 #include <string>
 #include <caffe.pb.h>
-#include <opencv2/dnn/nms.inl.hpp>
+#include "../nms.inl.hpp"
 
 namespace cv
 {

modules/dnn/src/nms.cpp

@@ -6,7 +6,7 @@
 // Third party copyrights are property of their respective owners.
 
 #include "precomp.hpp"
-#include <opencv2/dnn/nms.inl.hpp>
+#include <nms.inl.hpp>
 
 namespace cv
 {

modules/dnn/test/test_nms.cpp

@@ -0,0 +1,41 @@
+// 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.
+//
+// Copyright (C) 2017, Intel Corporation, all rights reserved.
+// Third party copyrights are property of their respective owners.
+
+#include "test_precomp.hpp"
+
+namespace cvtest
+{
+
+TEST(NMS, Accuracy)
+{
+    //reference results obtained using tf.image.non_max_suppression with iou_threshold=0.5
+    std::string dataPath = findDataFile("dnn/nms_reference.yml");
+    FileStorage fs(dataPath, FileStorage::READ);
+
+    std::vector<Rect> bboxes;
+    std::vector<float> scores;
+    std::vector<int> ref_indices;
+
+    fs["boxes"] >> bboxes;
+    fs["probs"] >> scores;
+    fs["output"] >> ref_indices;
+
+    const float nms_thresh = .5f;
+    const float score_thresh = .01f;
+    std::vector<int> indices;
+    cv::dnn::NMSBoxes(bboxes, scores, score_thresh, nms_thresh, indices);
+
+    ASSERT_EQ(ref_indices.size(), indices.size());
+
+    std::sort(indices.begin(), indices.end());
+    std::sort(ref_indices.begin(), ref_indices.end());
+
+    for(size_t i = 0; i < indices.size(); i++)
+        ASSERT_EQ(indices[i], ref_indices[i]);
+}
+
+}//cvtest