normalized_transforms.py 文件源码

def old_get_perspective_transform_normalized(p1,p2):
    """
    A small wrapper around cv2.getPerspectiveTransform, with normalization of
    point locations.

    """

    return cv2.getPerspectiveTransform(p1,p2)

    mu1 = p1.mean(axis=0)
    std1 = p1.std(axis=0)
    mu2 = p2.mean(axis=0)
    std2 = p2.std(axis=0)

    p1_ = (p1 - mu1) / std1
    p2_ = (p2 - mu2) / std2

    H_ = cv2.getPerspectiveTransform(p1_,p2_)
    A1 = np.array([[1.0/std1[0], 0.0, -mu1[0]/std1[0]],
                   [0, 1.0/std1[1], -mu1[1]/std1[1]],
                   [0,0,1.0]])
    A2inv = np.array([[std2[0], 0.0, mu2[0]],
                   [0, std2[1], mu2[1]],
                   [0,0,1.0]])
    H = A2inv.dot(H_).dot(A1)
    return H