Secure image cryptosystem with unique key streams via hyper-chaotic system

- Cryptanalyzing Norouzi et al.'s scheme to demonstrate its security weaknesses.
- Developing an attack scenario to break the Norouzi et al.'s cipher.
- Proposing an advanced version of Norouzi et al.'s scheme to remedy its security weakness.
- The proposed scheme resists several attacks such as known/chosen-plain-image attacks.
- Results assure the effectiveness of the proposed image encryption scheme.

This paper cryptanalyses the hyper-chaotic image encryption scheme developed by Norouzi et al. and presents a chosen-plain-image attack scenario to reveal its generated key stream. The recovered key stream can be used to decrypt any future related cipher-image without having the secret key. In addition, the paper introduces an advanced version of the underlying image encryption scheme to overcome its security shortcomings. Specifically, the proposed cipher generates a unique key stream for each distinct plain-image based on its fingerprint. This thwarts the chosen-plain-image attacks and enhances the security level of the proposed scheme. Finally, the experimental results confirm the robustness of the proposed image cipher against different types of attacks.