Merge pull request #27582 from MaximSmolskiy:take_into_account_overflow_for_connected_components

Take into account overflow for connected components #27582

### Pull Request Readiness Checklist

Fix #27568 

The problem was caused by a label type overflow (`debug_example.npy` contains `92103` labels, that doesn't fit in the `CV_16U` (`unsigned short`) type). If pass `CV_32S` instead of `CV_16U` as `ltype` - everything will be calculated successfully

Added overflow detection to throw exception with a clear error message instead of strange segfault/assertion error

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
- [x] 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.
- [x] The feature is well documented and sample code can be built with the project CMake

modules/imgproc/test/test_connectedcomponents.cpp

@@ -798,7 +798,47 @@ TEST(Imgproc_ConnectedComponents, 4conn_regression_21366)
     }
 }
 
+TEST(Imgproc_ConnectedComponents, regression_27568)
+{
+    Mat image = Mat::zeros(Size(512, 512), CV_8UC1);
+    for (int row = 0; row < image.rows; row += 2)
+    {
+        for (int col = 0; col < image.cols; col += 2)
+        {
+            image.at<uint8_t>(row, col) = 1;
+        }
+    }
 
+    for (const int connectivity : {4, 8})
+    {
+        for (const int ccltype : {CCL_DEFAULT, CCL_WU, CCL_GRANA, CCL_BOLELLI, CCL_SAUF, CCL_BBDT, CCL_SPAGHETTI})
+        {
+            {
+                Mat labels, stats, centroids;
+                try
+                {
+                    connectedComponentsWithStats(
+                        image, labels, stats, centroids, connectivity, CV_16U, ccltype);
+                    ADD_FAILURE();
+                }
+                catch (const Exception& exception)
+                {
+                    EXPECT_TRUE(
+                        strstr(
+                            exception.what(),
+                            "Total number of labels overflowed label type. Try using CV_32S instead of CV_16U as ltype"));
+                }
+            }
+
+            {
+                Mat labels, stats, centroids;
+                EXPECT_NO_THROW(
+                    connectedComponentsWithStats(
+                        image, labels, stats, centroids, connectivity, CV_32S, ccltype));
+            }
+        }
+    }
+}
 
 }
 } // namespace