Performance Evaluation of Some Selected Image Encryption Algorithms

Abstract

Context: A medical image contains sensitive information critical to patient’s diagnosis by medical personnel hence, requires privacy and optimum security to preserve for future use. Encryption algorithms are known to be used to secure medical data such as images but their performance varies. Most encryption algorithms are characterised by high computational time, high memory usage and image lossy problem after encryption. Objective: This research addresses some of these problems by comparing the performance of four encryption algorithms: Advanced Encryption Standard (AES), CAST, Blowfish, and Enhanced Data Encryption Standard (E-DES) algorithms when applied on medical images. Method: The evaluation was conducted using five image samples of varying sizes, and several metrics were observed, including encryption time, decryption time, output byte, memory usage, mean square error (MSE), and peak signal-to-noise ratio (PSNR). Results: The experimental findings indicated that E-DES demonstrated superior performance in encryption time compared to other encryption algorithms, with an execution time of 4.08, 3.93, 3.16, 3.89 and 4.00seconds for Image A, Image B, Image C, Image D and Image E respectively while AES has the lowest memory usage. Conclusions: The findings of the comparison has added to the understanding of the effectiveness of specific image encryption algorithms and which can assist in resolving image security issues more quickly.