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压缩包的内容
里面有secret.txt文件，用ARCHPR工具套上字典，爆破压缩包密码。密码为pavilion
解压得到原图，并且有了加密后的图片，根据代码里的key和参数直接运行脚本解密水印图片：
import cv2
import numpy as np
import pywtclass WaterMarkDWT:def __init__(self, origin: str, watermark: str, key: int, weight: list):self.key = keyself.img = cv2.imread(origin)self.mark = cv2.imread(watermark)self.coef = weightdef arnold(self, img):r, c = img.shapep = np.zeros((r, c), np.uint8)a, b = 1, 1for k in range(self.key):for i in range(r):for j in range(c):x = (i + b * j) % ry = (a * i + (a * b + 1) * j) % cp[x, y] = img[i, j]return pdef deArnold(self, img):r, c = img.shapep = np.zeros((r, c), np.uint8)a, b = 1, 1for k in range(self.key):for i in range(r):for j in range(c):x = ((a * b + 1) * i - b * j) % ry = (-a * i + j) % cp[x, y] = img[i, j]return pdef get(self, size: tuple = (1200, 1200), flag: int = None):img = cv2.resize(self.img, size)img1 = cv2.cvtColor(img, cv2.COLOR_RGB2GRAY)img2 = cv2.cvtColor(self.mark, cv2.COLOR_RGB2GRAY)c = pywt.wavedec2(img2, 'db2', level=3)[cl, (cH3, cV3, cD3), (cH2, cV2, cD2), (cH1, cV1, cD1)] = cd = pywt.wavedec2(img1, 'db2', level=3)[dl, (dH3, dV3, dD3), (dH2, dV2, dD2), (dH1, dV1, dD1)] = da1, a2, a3, a4 = self.coefca1 = (cl - dl) * a1ch1 = (cH3 - dH3) * a2cv1 = (cV3 - dV3) * a3cd1 = (cD3 - dD3) * a4# Ensure all coefficients have the same shapeca1 = cv2.resize(ca1, (cD3.shape[1], cD3.shape[0]))waterImg = pywt.waverec2([ca1, (ch1, cv1, cd1)], 'db2')waterImg = np.array(waterImg, np.uint8)waterImg = self.deArnold(waterImg)kernel = np.ones((3, 3), np.uint8)if flag == 0:waterImg = cv2.erode(waterImg, kernel)elif flag == 1:waterImg = cv2.dilate(waterImg, kernel)return waterImgif __name__ == '__main__':img = 'a.png'watermark = 'newImg.png'k = 20xs = [0.2, 0.2, 0.5, 0.4]W1 = WaterMarkDWT(img, watermark, k, xs)extracted_watermark = W1.get()cv2.imwrite('提取出的水印.png', extracted_watermark) 
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