Research And Implementation Of Audio Encryption Technology For Mobile Terminal In IOS System

Digital audio is increasingly used in offline scenes in life.Digital audio is stored in binary.As an information carrier,it is easy to copy and edit.It can carry a lot of private information,and even some audio contains important state secrets.Information,if tampered with,can pose a serious threat to national security.The encryption protection of audio files at home and abroad is mainly through some encryption and decryption algorithms,but these encryption and decryption algorithms have problems such as poor security and slow encryption speed when processing massive file data.Based on this,for the commonly used audio formats WAV and AMR,a content association key algorithm combined with interval algorithms is proposed to encrypt the voice data.The first is the encryption of WAV audio data.Because WAV audio files are a kind of low-entropy data,extracting the content association key algorithm combined with the interval algorithm directly cannot convert WAV audio files into high-entropy data.After the key information of the audio data,the SM4 algorithm of the national security algorithm is firstly used to perform lossless block encryption processing on the key data,and then the content association key algorithm processing combined with the interval algorithm is performed to complete the encryption operation and generate corresponding Key structural unit;for AMR audio data,first parse the file header,determine the audio data specifications,locate the start and end points of the audio data to the key position,and then perform content correlation key algorithm processing combined with the interval algorithm and generate the corresponding secret Key unit structure.Finally,the audio encryption and decryption module is implemented on the i OS system.Files can be obtained in the local sandbox,or converted into WAV or AMR audio files through Audio Record recording,and then multi-threaded encryption operations are performed on WAV audio and AMR audio files.The encrypted key is uploaded to the corresponding key server,and the ciphertext is stored in the local database.The decryption operation of the WAV audio file and the AMR audio file is the reverse process of the encryption operation.The experimental test mainly tests the encryption and decryption algorithm and the function of the encryption and decryption module.The encryption algorithm test includes the subjective scoring test MOS average opinion method.The objective test analysis is performed through S4 BAudio Studio and Audacity to illustrate the good encryption effect of the encryption algorithm.