cat置乱算法Python
时间: 2023-07-22 21:44:07 浏览: 46
CAT(Cellular Automaton Transform)置乱算法是一种图像加密算法,基于元胞自动机的置乱和扰动。以下是一个简单的Python实现:
```python
from PIL import Image
def cat(image_path, iterations):
# 读取图像
image = Image.open(image_path)
width, height = image.size
# 初始化元胞自动机
rule_num = 30
rule = [(rule_num >> i) & 1 for i in range(8)]
ca = [0] * width
ca[width // 2] = 1
# 迭代置换
for i in range(iterations):
new_image = Image.new('RGB', (width, height))
for x in range(width):
for y in range(height):
# 元胞自动机变换
ca = [rule[(ca[(x - 1) % width] << 2) + (ca[x] << 1) + ca[(x + 1) % width]] for x in range(width)]
# 像素置换
new_x = (x + ca[x]) % width
new_y = (y + ca[new_x]) % height
new_image.putpixel((new_x, new_y), image.getpixel((x, y)))
image = new_image
# 保存加密后的图像
image.save('encrypted.png')
if __name__ == '__main__':
cat('image.png', 10)
```
其中,`image_path`参数为待加密的图像路径,`iterations`参数为迭代次数。该算法通过不断迭代元胞自动机和像素置换来实现加密。