Comments on Test Methods of Encryption and Decryption Speeds of Image Cryptosystems

It is easy to design an image encryption scheme with good security but slow encryption speed. To effectively measure the encryption and decryption speeds of image cryptosystems, some effective methods are suggested to evaluate their processing speeds. Using MATLAB, C#, $\mathbf{C}++$ and Wolfram languages, two image cryptosystems, an AES based system and a unified system, are implemented to compare their processing speeds. Then some remarks for the comparative analysis of encryption and decryption speeds are given. This work provides reference measures for relatively fairly comparing the processing speeds of various image encryption systems, and suggests that the encryption and decryption speeds of image cryptosystem based on AES be used as the benchmark for evaluating the processing speeds of image cryptosystems based on chaos.