diff --git a/modules/imgproc/include/opencv2/imgproc/hal/interface.h b/modules/imgproc/include/opencv2/imgproc/hal/interface.h
index 23eb0baa40..f8dbcfe791 100644
--- a/modules/imgproc/include/opencv2/imgproc/hal/interface.h
+++ b/modules/imgproc/include/opencv2/imgproc/hal/interface.h
@@ -21,6 +21,26 @@
 #define CV_HAL_MORPH_DILATE 1
 //! @}
 
+//! @name Threshold types
+//! @sa cv::ThresholdTypes
+//! @{
+#define CV_HAL_THRESH_BINARY      0
+#define CV_HAL_THRESH_BINARY_INV  1
+#define CV_HAL_THRESH_TRUNC       2
+#define CV_HAL_THRESH_TOZERO      3
+#define CV_HAL_THRESH_TOZERO_INV  4
+#define CV_HAL_THRESH_MASK        7
+#define CV_HAL_THRESH_OTSU        8
+#define CV_HAL_THRESH_TRIANGLE    16
+//! @}
+
+//! @name Adaptive threshold algorithm
+//! @sa cv::AdaptiveThresholdTypes
+//! @{
+#define CV_HAL_ADAPTIVE_THRESH_MEAN_C     0
+#define CV_HAL_ADAPTIVE_THRESH_GAUSSIAN_C 1
+//! @}
+
 //! @}
 
 #endif
diff --git a/modules/imgproc/src/thresh.cpp b/modules/imgproc/src/thresh.cpp
index 5a802b915f..b87f48e67c 100644
--- a/modules/imgproc/src/thresh.cpp
+++ b/modules/imgproc/src/thresh.cpp
@@ -1549,7 +1549,7 @@ void cv::adaptiveThreshold( InputArray _src, OutputArray _dst, double maxValue,
         Mat srcfloat,meanfloat;
         src.convertTo(srcfloat,CV_32F);
         meanfloat=srcfloat;
-        GaussianBlur(srcfloat, meanfloat, Size(blockSize, blockSize), 0, 0, BORDER_REPLICATE);
+        GaussianBlur(srcfloat, meanfloat, Size(blockSize, blockSize), 0, 0, BORDER_REPLICATE|BORDER_ISOLATED);
         meanfloat.convertTo(mean, src.type());
     }
     else