CCM-PRNG: Pseudo-random bit generator based on cross-over chaotic map and its application in image encryption

Random numbers are the critical components of most security algorithms. Generating random numbers from a natural source or any deterministic algorithm suffers from shorter periods, inefficient energy consumption, smaller keyspace, etc. This work proposes a technique to generate random numbers with reduced complexity while increasing the keyspace and period of the random numbers. This work presents a novel method of cross-over operation on two chaotic maps to design a new hybrid chaotic map. The Pseudorandom Number Generator (PRNG) is constructed from the newly designed chaotic map, and the bit sequences are analyzed to justify their security strength. It is then applied to encrypt the images, and their properties are investigated. The proposed system is measured to have a 21.9% increase in keyspace and stronger key sensitivity. The correlation coefficient and entropy of ciphered images were shown to have a uniform distribution of pixel values. The average number of pixels change rate (NPCR) in ciphered images is calculated to be 99.4694%. The unified average changing intensity (UACI) is averaged at 33.4211%. The experimental analysis validates the competence of the proposed chaotic system for cryptography.