如何读取PNG并将数据从tiff文件添加到其中，并将其保存为另一个tiff？

import numpy as np
import cv2
from PIL import Image

png_image = cv2.imread('input.png', cv2.IMREAD_UNCHANGED)

tiff_image = Image.open('input.tiff')
tiff_data = np.array(tiff_image)

png_image[..., :3] = tiff_data[..., :3]

cv2.imwrite('output.tiff', png_image)