PROPOSING A NEW METHOD FOR ENCRYPTING SATELLITE IMAGES BASED ON HASH FUNCTION AND CHAOS PARAMETERS

Abstract. Due to the importance of providing security in satellite imagery and their transmission, in this paper, a new method for encrypting satellite images based on Hash key-based symmetric cryptographic algorithm is proposed which is developed by combining the generated key and chaos mapping parameters. The benefits of this algorithm are high security, high sensitivity and using dynamic encryption blocks. The proposed algorithm consists of three main parts: in the first section, the encryption key is created using the SHA-512 Hash function. In the second section, the initial values and the parameters of the mapping Chaos are determined by the algebraic functions that are related to the primary key. In the third section, with the help of the encryption block, the encrypted image is finally obtained. The purpose of this article is to increase the security of encrypting satellite images by creating an unspecified encryption block to deal with a variety of attacks. In this regard, both aspects of security and performance of the proposed algorithm have been analysed and the results are evaluated.