Look-up table based chaotic encryption of audio files

This paper proposes a novel look-up table based chaotic encryption scheme suitable for securing audio signals using a simple two dimensional nonlinear map. In the proposed method, we use a single chaotic trajectory whose period is equal to 65536. The iterated solutions of the chosen map are sorted in ascending order and indexed to create a look-up table. The initial conditions are treated as keys. The captured analog audio signal is digitized using sampling and quantization technique. The quantized binary data are grouped into 16-bit blocks and the corresponding decimal number times the chosen chaotic trajectory is iterated and the associated index value is referred from the look-up table. The process is repeated for all 16-bit blocks of our audio Me, to generate the encrypted audio file. The advantage of the proposed method is that the size of the encrypted file size is same as that of the original Me.