message: Do not use = 0 for a cv::Mat.
  There are several operator= overloads and some compilers can be confused.
diff: @@ -3924,7 +3924,7 @@ bool findChessboardCornersSB(cv::InputArray image_, cv::Size pattern_size,
  {
  meta_.create(int(board.rowCount()),int(board.colCount()),CV_8UC1);
  cv::Mat meta = meta_.getMat();
  - meta = 0;
  + meta.setTo(cv::Scalar::all(0));
  for(int row =0;row < meta.rows-1;++row)
  {
  for(int col=0;col< meta.cols-1;++col)
  