message: imgproc: sigma2=sigma1 in top-level function of GaussianBlur
diff: @@ -635,6 +635,9 @@ void GaussianBlur(InputArray _src, OutputArray _dst, Size ksize,
  return;
  }
  + if (sigma2 <= 0)
  + sigma2 = sigma1;
  +
  bool useOpenCL = ocl::isOpenCLActivated() && _dst.isUMat() && _src.dims() <= 2 &&
  _src.rows() >= ksize.height && _src.cols() >= ksize.width &&
  ksize.width > 1 && ksize.height > 1;
  