Implementation of MS Circle Map in Digital Image Encryption

Digital data protection is important to prevent changes and manipulation of digital data by unauthorized parties. Reliable, secure and fast digital data security techniques are needed. One such technique is the use of cryptography. This paper discusses the implementation of MS Circle Map in cryptography for data security. The object used in this study is a digital image. Encryption algorithms that use chaos functions to secure digital data must have a high key space and fast processing time. This research was conducted by designing an algorithm for encryption and decryption and then implementing it with Python programming. The MS Circle function has six parameters (x0,r, λ, K, Ω, t) to obtain a sufficiently high key space 1.889×101,267 1.889×101,267combination and has a key sensitivity level of 10-16. The MS Circle Map function has high resistance to various attacks. This is evidenced by the results from the key space, initial value sensitivity test, goodness of fit test, entropy, correlation coefficient, NPCR test, UACI test and image quality test. Based on the tests carried out, it was found that the MS Circle Map algorithm successfully resisted brute force, statistical, and differential attacks. The results of image quality tests using MSE and PSNR showed that the digital image decryption stage was successful and the original image could be restored.