Speech encryption using two dimensional chaotic maps

Speech encryption is used to convert clear speech into unintelligible signal in order to avoid eavesdropping for this purpose, cryptographic techniques and chaotic maps can be applicable. In this paper, a speech cryptosystem based on substitution and permutation is presented. The speech signal has been processed using different discrete transforms. Then the system has been developed using different chaotic maps like 2D Logistic map, Henon map, and Baker. Different objective quality measures for speech have been used to measure the quality of encrypted and decrypted speech signals.