def compute_criterion(I_xx, I_yy, I_xy, sigma):
    """ Compute criterion function

    Args:
        I_xx: (h, w) np.array of 2nd derivatives in x direction
        I_yy: (h, w) np.array of 2nd derivatives in y direction
        I_xy: (h, w) np.array of 2nd derivatives in x-y direction
        sigma: scaling factor

    Returns:
        criterion: (h, w) np.array of scaled determinant of Hessian matrix
    """

    #
    # You code here
    #

    det = I_xx * I_yy - I_xy ** 2
    return sigma ** 4 * det