上传内容为基于Arnold变换的图像加密和解密程序，c语言编写。-From the contents of Arnold transform based image encryption and decryption procedures, c language.

本文提出了基于二维混沌映射的数字图像水印算法，混沌具有随机性、似噪声及对初始条件的极端敏感性等特点。将经过二维混沌映射置乱后的数字水印信号嵌入图像小波域的低频系数，实现了数字水印的隐蔽性、保密性和稳固性；利用二维混沌映射Arnold变换对水印信号进行置乱，不仅增强了水印信号保密性，同时有效提高了视觉上抵抗图像剪切攻击的能力。-In this paper, two-dimensional chaotic map based on digital image watermarking algorit

用C++实现对正方形bmp图像的Arnold变换，重复进行多次变换，并观察其周期性-In c++ implementation of the square of BMP image Arnold transform, repeated many times change, and observe its periodicity