Merge pull request #23688 from cpoerschke:4.x-pr-21959-prep

imgproc: add contour values check to IntelligentScissorsMB tests

Preparation for the #21959 changes as per @asmorkalov's https://github.com/opencv/opencv/pull/21959#issuecomment-1560511500 suggestion.

### Pull Request Readiness Checklist

See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request

- [X] I agree to contribute to the project under Apache 2 License.
- [X] To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
- [X] The PR is proposed to the proper branch
- [ ] There is a reference to the original bug report and related work
- [X] There is accuracy test, performance test and test data in opencv_extra repository, if applicable
      Patch to opencv_extra has the same branch name.
- [ ] The feature is well documented and sample code can be built with the project CMake

modules/imgproc/test/test_intelligent_scissors.cpp

@@ -147,11 +147,72 @@ void show(const Mat& img, const std::vector<Point> pts)
     }
 }
 
+Size estimateContourSize(const std::vector<Point>& pts)
+{
+    Size s(0,0);
+    for (size_t i = 0; i < pts.size(); i++)
+    {
+        if (s.width < pts[i].x)
+            s.width = pts[i].x;
+        if (s.height < pts[i].y)
+            s.height = pts[i].y;
+    }
+    return s;
+}
+
+int contoursAreaPixelsMismatch(const std::vector<Point>& pts, const std::vector<Point>& gt)
+{
+    Size ptsSize = estimateContourSize(pts);
+    Size gtSize = estimateContourSize(gt);
+
+    Size imgSize(std::max(ptsSize.width, gtSize.width)+1, std::max(ptsSize.height, gtSize.height)+1);
+    Mat ptsArea = Mat::zeros(imgSize, CV_8UC1);
+    Mat gtArea = Mat::zeros(imgSize, CV_8UC1);
+
+    std::vector<std::vector<Point>> pts_wrapped = {pts};
+    std::vector<std::vector<Point>> gt_wrapped = {gt};
+    drawContours(ptsArea, pts_wrapped, -1, Scalar(255), FILLED);
+    drawContours(gtArea, gt_wrapped, -1, Scalar(255), FILLED);
+
+    Mat uni = ptsArea | gtArea;
+    Mat intersection = ptsArea & gtArea;
+    bitwise_not(intersection, intersection);
+    Mat delta = uni & intersection;
+
+    return countNonZero(delta);
+}
+
+void checkContour(std::vector<Point>& pts,
+                  const bool backward = false,
+                  int allowed_mismatch = 0)
+{
+    const ::testing::TestInfo* const test_info = ::testing::UnitTest::GetInstance()->current_test_info();
+    CV_Assert(test_info);
+    const std::string name = std::string(cvtest::TS::ptr()->get_data_path() + "imgproc/" + test_info->test_case_name() + "-" + test_info->name() + (backward ? "-backward" : "") + ".xml");
+
+    std::vector<Point> reference_pts;
+#ifdef GENERATE_TEST_DATA
+    {
+        cv::FileStorage fs(name, cv::FileStorage::WRITE);
+        fs << "pts" << pts;
+    }
+    reference_pts = pts;
+#else
+    FileStorage fs(name, FileStorage::READ);
+    read(fs["pts"], reference_pts, std::vector<Point>());
+#endif
+
+    if (!allowed_mismatch)
+        EXPECT_EQ(pts, reference_pts);
+    else
+        EXPECT_LE(contoursAreaPixelsMismatch(pts, reference_pts), allowed_mismatch);
+}
+
 TEST(Imgproc_IntelligentScissorsMB, rect)
 {
     segmentation::IntelligentScissorsMB tool;
-
+    Mat image = getTestImage1();
-    tool.applyImage(getTestImage1());
+    tool.applyImage(image);
 
     Point source_point(50, 30);
     tool.buildMap(source_point);
@@ -159,15 +220,18 @@ TEST(Imgproc_IntelligentScissorsMB, rect)
     Point target_point(100, 30);
     std::vector<Point> pts;
     tool.getContour(target_point, pts);
+    checkContour(pts);
+    show(image, pts);
 
-    tool.applyImage(getTestImage2());
+    Mat image2 = getTestImage2();
+    tool.applyImage(image2);
 
     tool.buildMap(source_point);
 
     std::vector<Point> pts2;
     tool.getContour(target_point, pts2, true/*backward*/);
-
+    checkContour(pts2, true/*backward*/);
-    EXPECT_EQ(pts.size(), pts2.size());
+    show(image2, pts2);
 }
 
 TEST(Imgproc_IntelligentScissorsMB, lines)
@@ -182,8 +246,7 @@ TEST(Imgproc_IntelligentScissorsMB, lines)
     Point target_point(150, 50);
     std::vector<Point> pts;
     tool.getContour(target_point, pts);
-
+    checkContour(pts);
-    EXPECT_EQ((size_t)121, pts.size());
     show(image, pts);
 }
 
@@ -201,8 +264,7 @@ TEST(Imgproc_IntelligentScissorsMB, circles)
     Point target_point(150, 50);
     std::vector<Point> pts;
     tool.getContour(target_point, pts);
-
+    checkContour(pts);
-    EXPECT_EQ((size_t)101, pts.size());
     show(image, pts);
 }
 
@@ -218,13 +280,10 @@ TEST(Imgproc_IntelligentScissorsMB, circles_gradient)
     Point target_point(150, 50);
     std::vector<Point> pts;
     tool.getContour(target_point, pts);
-
+    checkContour(pts);
-    EXPECT_EQ((size_t)101, pts.size());
     show(image, pts);
 }
 
-#define PTS_SIZE_EPS 2
-
 TEST(Imgproc_IntelligentScissorsMB, grayscale)
 {
     segmentation::IntelligentScissorsMB tool;
@@ -238,10 +297,7 @@ TEST(Imgproc_IntelligentScissorsMB, grayscale)
     Point target_point(413, 155);
     std::vector<Point> pts;
     tool.getContour(target_point, pts);
-
+    checkContour(pts, false, 2);
-    size_t gold = 206;
-    EXPECT_GE(pts.size(), gold - PTS_SIZE_EPS);
-    EXPECT_LE(pts.size(), gold + PTS_SIZE_EPS);
     show(image, pts);
 }
 
@@ -260,10 +316,7 @@ TEST(Imgproc_IntelligentScissorsMB, check_features_grayscale_1_0_0_zerro_crossin
     Point target_point(413, 155);
     std::vector<Point> pts;
     tool.getContour(target_point, pts);
-
+    checkContour(pts, false, 11);
-    size_t gold = 207;
-    EXPECT_GE(pts.size(), gold - PTS_SIZE_EPS);
-    EXPECT_LE(pts.size(), gold + PTS_SIZE_EPS);
     show(image, pts);
 }
 
@@ -282,10 +335,7 @@ TEST(Imgproc_IntelligentScissorsMB, check_features_grayscale_1_0_0_canny)
     Point target_point(413, 155);
     std::vector<Point> pts;
     tool.getContour(target_point, pts);
-
+    checkContour(pts, false, 6);
-    size_t gold = 201;
-    EXPECT_GE(pts.size(), gold - PTS_SIZE_EPS);
-    EXPECT_LE(pts.size(), gold + PTS_SIZE_EPS);
     show(image, pts);
 }
 
@@ -303,10 +353,7 @@ TEST(Imgproc_IntelligentScissorsMB, check_features_grayscale_0_1_0)
     Point target_point(413, 155);
     std::vector<Point> pts;
     tool.getContour(target_point, pts);
-
+    checkContour(pts, false, 4);
-    size_t gold = 166;
-    EXPECT_GE(pts.size(), gold - PTS_SIZE_EPS);
-    EXPECT_LE(pts.size(), gold + PTS_SIZE_EPS);
     show(image, pts);
 }
 
@@ -324,10 +371,7 @@ TEST(Imgproc_IntelligentScissorsMB, check_features_grayscale_0_0_1)
     Point target_point(413, 155);
     std::vector<Point> pts;
     tool.getContour(target_point, pts);
-
+    checkContour(pts, false, 2);
-    size_t gold = 197;
-    EXPECT_GE(pts.size(), gold - PTS_SIZE_EPS);
-    EXPECT_LE(pts.size(), gold + PTS_SIZE_EPS);
     show(image, pts);
 }
 
@@ -344,10 +388,7 @@ TEST(Imgproc_IntelligentScissorsMB, color)
     Point target_point(413, 155);
     std::vector<Point> pts;
     tool.getContour(target_point, pts);
-
+    checkContour(pts, false, 2);
-    size_t gold = 205;
-    EXPECT_GE(pts.size(), gold - PTS_SIZE_EPS);
-    EXPECT_LE(pts.size(), gold + PTS_SIZE_EPS);
     show(image, pts);
 }
 
@@ -365,10 +406,7 @@ TEST(Imgproc_IntelligentScissorsMB, color_canny)
     Point target_point(413, 155);
     std::vector<Point> pts;
     tool.getContour(target_point, pts);
-
+    checkContour(pts, false, 2);
-    size_t gold = 200;
-    EXPECT_GE(pts.size(), gold - PTS_SIZE_EPS);
-    EXPECT_LE(pts.size(), gold + PTS_SIZE_EPS);
     show(image, pts);
 }
 
@@ -397,10 +435,7 @@ TEST(Imgproc_IntelligentScissorsMB, color_custom_features_edge)
     Point target_point(413, 155);
     std::vector<Point> pts;
     tool.getContour(target_point, pts);
-
+    checkContour(pts, false, 2);
-    size_t gold = 201;
-    EXPECT_GE(pts.size(), gold - PTS_SIZE_EPS);
-    EXPECT_LE(pts.size(), gold + PTS_SIZE_EPS);
     show(image, pts);
 }
 
@@ -427,10 +462,7 @@ TEST(Imgproc_IntelligentScissorsMB, color_custom_features_all)
     Point target_point(413, 155);
     std::vector<Point> pts;
     tool.getContour(target_point, pts);
-
+    checkContour(pts, false, 9);
-    size_t gold = 201;
-    EXPECT_GE(pts.size(), gold - PTS_SIZE_EPS);
-    EXPECT_LE(pts.size(), gold + PTS_SIZE_EPS);
     show(image, pts);
 }
 
@@ -456,10 +488,7 @@ TEST(Imgproc_IntelligentScissorsMB, color_custom_features_edge_magnitude)
     Point target_point(413, 155);
     std::vector<Point> pts;
     tool.getContour(target_point, pts);
-
+    checkContour(pts, false, 9);
-    size_t gold = 201;
-    EXPECT_GE(pts.size(), gold - PTS_SIZE_EPS);
-    EXPECT_LE(pts.size(), gold + PTS_SIZE_EPS);
     show(image, pts);
 }