def get_total_num_filters(J, L):
    """ Compute the total number of filters

        Parameters:
            J -- scale of the scattering
            L -- number of orientation for the scattering

        Returns:
            num_filters -- the total number of filters
    """
    num_filters = 0
    for j in range(2,J+1):
        num_filters += j *L
    return num_filters