Image Encryption Algorithm Through Hill Cipher, Shift 128 Cipher, and Logistic Map Using Python

Abstract

One of the cryptographic approaches is the Hill Cipher. A square key matrix must have an inverse modulo in the Hill Cipher algorithm. The unimodular matrix is one of the special matrices that has an inverse. In the encryption process, a unimodular matrix can be utilized as a key matrix. The goal of this study is to demonstrate a safe digital image data alternative. Symmetric cryptography is the type of encryption utilized. The described approach uses a Logistic Map to construct a unimodular matrix. To begin, we employ an identity matrix to obtain a unimodular matrix. The encryption mechanism in this study is modulo matrix multiplication. Because an incomplete partition may arise as a result of a file, we must apply Shift Cipher 128 encryption in the next step. We utilize Shift Cipher 128 to encrypt the imperfect partition, especially if the size is a large enough prime integer. The results reveal that the photos are well encrypted and difficult for third parties to decrypt. This encryption methods also assures that the encrypted and decrypted file sizes are identical to the original file sizes. As a result, the Hill cipher works well with the combination of these techniques for encrypting digital images.