Chaotic image encryption system using phase-magnitude transformation and pixel substitution

摘要: We proposed an algorithm to encrypt image in hybrid domain, frequency and time domains. The method is a private key encryption system with two main units, chaotic phase-magnitude transformation unit pixel substitution unit. Chaotic works domain 2-D DFT performed on the plain change domain. A function, tent map, used generate pseudo random image, which are combined Bernoulli map applied produce another that mixing encrypted nonlinearly. performance of analysed using computer simulation. distribution histogram uniform. Chi-square value for our considerably low. MSE big enough. correlation coefficients all three directions sufficiently small. total length large enough resist against any brute-force attack. scheme robust chosen plaintext attacks too. system, together, more secure than most single systems.