Audio Encryption Algorithm Based On Chaotic System

With the rapid development of mobile Internet,cloud computing technology and multimedia applications,information security issues such as national intelligence and personal privacy security have become increasingly prominent.Among them,the chaotic encryption of audio and other multimedia data is one of the effective methods of audio information protection.However,the current research on chaotic audio encryption mostly focuses on the design of chaotic systems,and uses a more novel chaotic system to protect audio,although the generated pseudo-random sequences have passed random tests such as NIST and TestUO1 in randomness.However,the encryption method for audio is still weak,and it is difficult for a single XOR operation to withstand strict cryptographic tests.Secondly,the characteristics of internal randomness and initial value sensitivity of chaotic systems,especially single chaotic maps,have unavoidable chaotic degradation characteristics in digital systems with limited accuracy.That is,with the continuous iteration of digital chaotic systems,the results will be It gradually changes from a random chaotic state to a linear periodic state,which is no longer suitable for application in the encryption process.However,multimedia data such as audio has the characteristics of large information and large amount of redundancy.If the degradation of chaos is not considered in the chaotic cryptographic algorithm,it is difficult to ensure the overall encryption effect of the audio data.In consideration of the above problems,this paper designs a chaotic encryption algorithm for audio from different angles.Firstly,the complex chaotic system is introduced into the audio encryption algorithm.The complex domain expands the dimension and randomness of the chaotic system and the key space of the audio encryption algorithm,making brute force cracking more difficult to achieve.Secondly,the anti-synchronization control method is used in the encryption and decryption process to drive the anti-synchronization effect of the system,improve the robustness of the encryption algorithm and the dependence on the initial value,and reduce the difficulty of key management and key distribution.Finally,an irreversible and highly sensitive hash function(Hash function)is added to the audio algorithm during key generation,and the plaintext audio is compressed into a fixed-length hash value using the Hash function,and then applied to the initial value of the chaotic system In the calculation process,because the hash value and the plain text are highly one-to-one corresponding,even if the attacker can obtain the key,the cipher text cannot be deciphered,and the one-time encryption of the encryption algorithm is guaranteed.On the other hand,considering the degradation of digital chaos,a crosstalk STBCS is proposed based on the Sine-Transform-Based Chaotic System(STBCS).Using LS(Logistic-Sine)mapping with initial value sensitivity and adding small amplitude disturbances,the chaotic state attenuation of the digital system is effectively reduced.In addition,ZUC's stream cryptographic algorithm(ZUC)was added to the encryption process.The initial key was expanded to 512 bits to increase the key space of the algorithm.At the same time,in order to improve the encryption efficiency of audio encryption,the ZUC algorithm was used to generate key words.A round key expansion structure with superimposed XOR is designed to form a ZUC algorithm in the form of block ciphers.