PhD student from Computer Science Department at the University of Technology Sondos Ibrahim Mahdi designed a proposed method to encrypt speech.
She mentioned in her thesis that this method covers two parts encryption and decryption code. The encryption process is achieved through four key phases of mixing and staggers to the voice signal time domain and frequency domain through the secret keys. The stages are: retail, generate the key, change locations, change values.
she showed that the overlap technique is a technique that was used to segment the audio signal into overlapping sections to increase the strength of encryption. And that the proposed method is based on the generation of secret keys in order to confuse and confuse the original audio signal to produce a signal in noise and unintelligible. The technique used to generate keys based on the use of Hybrid Maps chaos unilateral dimensional chaos with two-dimensional maps.
And encryption keyshave high sensitivity to change very slightly on the value of the key which produced encrypted signal totally different and the system has a large area of the keys, making them impractical attack.
In addition, the proposed method succeeded encoding audio signal in short time where it takes of encryption process / decryption code 40000 for a sample is 0.0219 seconds and compared with the previous work demonstrated that the recent study is 3.84 times fast.