Method MulTransposed

multiplies matrix by its transposition from the left or from the right

public static void MulTransposed(InputArray src, OutputArray dst, bool aTa, InputArray delta = default, double scale = 1, int dtype = -1)

src InputArray: The source matrix
dst OutputArray: The destination square matrix
aTa bool: Specifies the multiplication ordering; see the description below
delta InputArray: The optional delta matrix, subtracted from src before the multiplication. When the matrix is empty ( delta=Mat() ), it’s assumed to be zero, i.e. nothing is subtracted, otherwise if it has the same size as src, then it’s simply subtracted, otherwise it is "repeated" to cover the full src and then subtracted. Type of the delta matrix, when it's not empty, must be the same as the type of created destination matrix, see the rtype description
scale double: The optional scale factor for the matrix product
dtype int: When it’s negative, the destination matrix will have the same type as src . Otherwise, it will have type=CV_MAT_DEPTH(rtype), which should be either CV_32F or CV_64F