diff --git a/modules/stitching/test/test_blenders.cpp b/modules/stitching/test/test_blenders.cpp
index b27af8d867..f511fea4de 100644
--- a/modules/stitching/test/test_blenders.cpp
+++ b/modules/stitching/test/test_blenders.cpp
@@ -73,6 +73,6 @@ TEST(MultiBandBlender, CanBlendTwoImages)
     Mat result; result_s.convertTo(result, CV_8U);
 
     Mat expected = imread(string(cvtest::TS::ptr()->get_data_path()) + "stitching/baboon_lena.png");
-    double rmsErr = norm(expected, result, NORM_L2) / sqrt(expected.size().area());
+    double rmsErr = norm(expected, result, NORM_L2) / sqrt(double(expected.size().area()));
     ASSERT_LT(rmsErr, 1e-3);
 }