Python+openCV：模拟数字水印的嵌入和提取

最近在学习OpenCV，看的是微信读书里的《OpenCV轻松入门：面向Python》，根据书上的例题，做了一些小程序

参考来源

《OpenCV轻松入门：面向Python》例3.15

加载原始图片

我从网上找了一张上海的图片，加载成了黑白照片

原始图

oriImg = cv2.imread("shanghai.jpg", 0)  # 0表示将图片转为黑白
r ,c = oriImg.shape
cv2.namedWindow("origin",cv2.WINDOW_NORMAL)  # 设置窗口尺寸，避免图片太大，显示不全
cv2.imshow("origin", oriImg)  # 显示图像
cv2.imwrite('OriginImg.png',oriImg)  # 保存图像

加载水印图片

水印图

水印照片的处理比原图复杂一点，主要是分为几步
1）因为我找个这个图有点小，所以我把图片放大了一点

watermark = cv2.imread("watermark.jpg", 0)
r1 ,c1 = watermark.shape
watermark = cv2.resize(watermark,(r1*6,c1*4))

2）图片处理一下，把图片转成0和1两个值

w1 = watermark[:,:]>200
watermark[w1] = 0
w2 = watermark[:,:]>200
watermark[w2] = 1

3）把水印图和原图做的一样大，方便后续处理

watermarkImg = np.zeros((r,c), dtype=np.uint8)
r1 ,c1 = watermark.shape
watermarkImg[600:600+r1,2000:2000+c1] = watermark
cv2.namedWindow("watermark",cv2.WINDOW_NORMAL)
cv2.imshow("watermark", watermarkImg)
cv2.imwrite('WatermarkImg.png',watermarkImg)

黑白水印图

水印嵌入

t254 = np.ones((r,c), dtype=np.uint8)*254 
imgH7 = cv2.bitwise_and(oriImg, t254)
resultImg = cv2.bitwise_or(imgH7, watermarkImg)
cv2.namedWindow("result",cv2.WINDOW_NORMAL)
cv2.imshow("result",resultImg)
cv2.imwrite('ResultImg.png',resultImg)

加入水印

水印解码

t1 = np.ones((r,c), dtype=np.uint8)
delImg = cv2.bitwise_and(resultImg, t1)
w3 = delImg[:,:]>0
delImg[w3] = 255
cv2.namedWindow("delete",cv2.WINDOW_NORMAL)
cv2.imshow("delete",delImg)
cv2.imwrite('DeleteImg.png',delImg)

提取水印

完整代码

import cv2
import numpy as np

# 加载原始图片
oriImg = cv2.imread("shanghai.jpg", 0)
r ,c = oriImg.shape
cv2.namedWindow("origin",cv2.WINDOW_NORMAL)  # 设置窗口尺寸
cv2.imshow("origin", oriImg)
cv2.imwrite('OriginImg.png',oriImg)

# 加载水印图片
watermark = cv2.imread("watermark.jpg", 0)
r1 ,c1 = watermark.shape
watermark = cv2.resize(watermark,(r1*6,c1*4))
w1 = watermark[:,:]>200
watermark[w1] = 0
w2 = watermark[:,:]>200
watermark[w2] = 1
watermarkImg = np.zeros((r,c), dtype=np.uint8)
r1 ,c1 = watermark.shape
watermarkImg[600:600+r1,2000:2000+c1] = watermark
cv2.namedWindow("watermark",cv2.WINDOW_NORMAL)
cv2.imshow("watermark", watermarkImg)
cv2.imwrite('WatermarkImg.png',watermarkImg)

# 水印嵌入
t254 = np.ones((r,c), dtype=np.uint8)*254 
imgH7 = cv2.bitwise_and(oriImg, t254)
resultImg = cv2.bitwise_or(imgH7, watermarkImg)
cv2.namedWindow("result",cv2.WINDOW_NORMAL)
cv2.imshow("result",resultImg)
cv2.imwrite('ResultImg.png',resultImg)

# 水印解码
t1 = np.ones((r,c), dtype=np.uint8)
delImg = cv2.bitwise_and(resultImg, t1)
w3 = delImg[:,:]>0
delImg[w3] = 255
cv2.namedWindow("delete",cv2.WINDOW_NORMAL)
cv2.imshow("delete",delImg)
cv2.imwrite('DeleteImg.png',delImg)

cv2.waitKey()
cv2.destroyAllWindows()