摘自opencv 源代码

 

void rotate(InputArray _src, OutputArray _dst, int rotateMode){    CV_Assert(_src.dims() <= 2);    CV_OCL_RUN(_dst.isUMat(), ocl_rotate(_src, _dst, rotateMode))    switch (rotateMode)    {    case ROTATE_90_CLOCKWISE:        transpose(_src, _dst);        flip(_dst, _dst, 1);        break;    case ROTATE_180:        flip(_src, _dst, -1);        break;    case ROTATE_90_COUNTERCLOCKWISE:        transpose(_src, _dst);        flip(_dst, _dst, 0);        break;    default:        break;    }}