下面的例子是将img2作为水印打到bg上，注意：img2是一个背景透明的png
import cv2
from PIL import Image
def merge_image(bg, img2, top_left):
# 打开背景
bg = Image.fromarray(bg.astype('uint8')).convert('RGB')
# 创建底图
target = Image.new('RGBA', (bg.size[0], bg.size[1]), (0, 0, 0, 0))
# 打开水印
img2_scale = img2.copy()
# img2_scale = cv2.resize(img2_scale, (w2, h2))
img2_scale = Image.fromarray(img2_scale.astype('uint8')).convert('RGBA')
# 分离透明通道
r, g, b, a = img2_scale.split()
# 将背景贴到底图
bg.convert("RGBA")
target.paste(bg, (0, 0))
# 将水印贴到底图
img2_scale.convert("RGBA")
startX = top_left[0]
startY = top_left[1]
target.paste(img2_scale, (startX, startY), mask=a)
target = np.array(target)
return target
bg = cv2.imread(r'bg.jpg')
img2 = cv2.imread(r'logo.png', cv2.IMREAD_UNCHANGED)
top_left = (10, 10)
res = merge_image(bg, img2, top_left)
cv2.imshow('1', res)
cv2.waitKey(100000)
