numpy 去除多张图片共同背景

import cv2
import numpy as np
#计算多张相似图片的共同背景
img1st = cv2.imread('24.png')
H,W, chanels = img1st.shape
cv2.imshow("1st image", cv2.resize(img1st ,(int(0.3*W),int(0.3*H)))) #原图像素高，缩小了了好显示
p = np.ones(img1st.shape)
for i in range(25,31): #加上第1张图，共7张图
    imgNew = cv2.imread('%d.png' % i)
    delta = imgNew == img1st #比较异同
    p *= delta # 逻辑与，全部图中相同的
cv2.imshow("background", cv2.resize(p*img1st ,(int(0.3*W),int(0.3*H)))) # 背景图

#p_any = p.sum(axis =2).astype("Bool") #逻辑或。任一通道为真则为真
#p_any = p_any.repeat(3).reshape(H,W,3)
#cv2.imshow("without background1", cv2.resize(img1st - p_any*img1st ,(int(0.3*W),int(0.3*H))))

p_all = p.prod(axis =2).astype("Bool") #求乘积（逻辑与）。任一通道为真则为真。更严，三通道都同的才算背景
p_all = p_all.repeat(3).reshape(H,W,3)
cv2.imshow("background removed", cv2.resize(img1st - p_all*img1st ,(int(0.3*W),int(0.3*H))))
cv2.waitKey()
cv2.destroyAllWindows()