隨著網路時代的來臨與進步，越來越多人利用網路去傳輸他們的資料或檔案，然而，忽略去保護資料的安全變成人們常犯的錯誤，這種疏忽給了有心人士去竊取你的檔案、重要資料，造成受害者蒙受重大損失。因此，資訊安全成為現今人們最重要的課題之一，越來越多人從事關於資訊安全的相關研究。在本篇論文中，我們嘗試將訊息先轉成二進制碼，然後透過互斥或進行加密，最後再利用最低有效位元演算法將加密過後的訊息藏匿到圖片中。實驗證實在絕大多數的情況下，人眼無法輕易分辨哪些圖片是有暗藏傳送者真正想傳送的訊息，且因為訊息在先前已用互斥或加密過，即便資料被有心人士盜取，他們也會因為沒有密鑰而無法將加密過後的訊息進行解密，從而達到保障資訊安全的目標。此外，我們所提出的方法並不會因為不同的檔案格式而受到限制。

With the advent and advancement of the Internet age, more and more people use the Internet to transmit their data or files. However, ignoring data security has become a common mistake. This negligence gives chances to hackers or intruders to steal their data or private information and makes the victims suffer from heavy losses. Therefore, information security has become one of the top issues today, more and more people are engaged in related research on information security. In this thesis, we try to convert the secret message into binary code, then encrypt it by adopting the exclusive-or cipher, and finally, we use the least significant bit algorithm to embed the ciphertext into the cover image. Experiments have confirmed that in most cases, the human visual systems cannot easily distinguish which images have been hidden the messages the sender really wants to send. Because the messages have been encrypted previously, even if they are stolen by hackers or intruders, it will also make them impossible to decrypt because they do not have the key, thereby achieving the goal of protecting information security. In addition, our proposed method can work for various file formats such as plain text, word, portable file format and etc.

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https://commons.wikimedia.org/wiki/File:Ascii-codes-table.png
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