flip函数

CV_EXPORTS_W void flip(InputArray src, OutputArray dst, int flipCode);

enum RotateFlags {
ROTATE_90_CLOCKWISE = 0, //Rotate 90 degrees clockwise
ROTATE_180 = 1, //Rotate 180 degrees clockwise
ROTATE_90_COUNTERCLOCKWISE = 2, //Rotate 270 degrees clockwise
};

 0 顺时针旋转90度
 1 顺时针旋转180度
 2 顺时针旋转270度
};