imgproc: disable IPP for GaussianBlur in case of ROI

modules/imgproc/src/smooth.cpp

@@ -1734,6 +1734,9 @@ static bool ipp_GaussianBlur( InputArray _src, OutputArray _dst, Size ksize,
                    int borderType )
 {
 #if IPP_VERSION_X100 >= 810
+    if ((borderType & BORDER_ISOLATED) == 0 && _src.isSubmatrix())
+        return false;
+
     int type = _src.type();
     Size size = _src.size();
 

modules/imgproc/test/ocl/test_filters.cpp

@@ -225,7 +225,7 @@ OCL_TEST_P(GaussianBlurTest, Mat)
         OCL_OFF(cv::GaussianBlur(src_roi, dst_roi, Size(ksize, ksize), sigma1, sigma2, borderType));
         OCL_ON(cv::GaussianBlur(usrc_roi, udst_roi, Size(ksize, ksize), sigma1, sigma2, borderType));
 
-        Near(CV_MAT_DEPTH(type) >= CV_32F ? 7e-5 : 1, false);
+        Near(CV_MAT_DEPTH(type) >= CV_32F ? 1e-3 : 4, CV_MAT_DEPTH(type) >= CV_32F);
     }
 }