The invention discloses an image
encryption method based on L-F
cascade chaos and 3D bit scrambling. Image
encryption is mainly divided into two steps: (1) 3D bit scrambling
encryption and (2)
diffusion operation. A novel L-F
cascade chaos is constructed, the problem that a blank window exists due to uneven distribution of Logistic is solved while the
rapidity of the Logistic is guaranteed, the chaos interval and number of parameters are increased, the secret
key space is increased, and the exhaustion
attack resistance of the
system is improved. According to the method, the randomness of scrambled
ciphertext is improved by adopting a 3D
cyclic shift bit scrambling mode, and the problem that a bit scrambling sequence is insensitive is solved. According to the method, high-order informationcontaining a large amount of
plaintext information and low-order information containing a small amount of
plaintext information are separately scrambled, so that the
noise attack resistance of the
system is improved. According to the
encryption system, the
plaintext SHA-256 is used for carrying out strong association on the
chaotic key, so that the plaintext sensitivity and the capability of resisting the
attack of the selected plaintext are effectively improved.