def _get_perspective_coeffs(startpoints, endpoints):
    """
    """
    matrix = []

    for p1, p2 in zip(endpoints, startpoints):
        matrix.append([p1[0], p1[1], 1, 0, 0, 0, -p2[0] * p1[0], -p2[0] * p1[1]])
        matrix.append([0, 0, 0, p1[0], p1[1], 1, -p2[1] * p1[0], -p2[1] * p1[1]])

    A = torch.tensor(matrix, dtype=torch.float)
    B = torch.tensor(startpoints, dtype=torch.float).view(8)
    res = torch.gels(B, A)[0]
    return res.squeeze_(1).tolist()