message: avoid copyTo(outputarray.getMat()) pattern
  leads to errors due 'const' modifier of getMat() method
  may be non-optimal with non-CPU data storage
diff: @@ -259,7 +259,7 @@ public:
  res_pyr[lvl - 1] += up;
  }
  dst.create(size, CV_32FCC);
  - res_pyr[0].copyTo(dst.getMat());
  + res_pyr[0].copyTo(dst);
  }
  float getContrastWeight() const CV_OVERRIDE { return wcon; }
  