Split Multi-Stage Vector Quantization Based Steganography for Secure Wideband Speech Coder

摘要

Speech steganography is a technique of covert communication which conveys secret speechhidden in cover digital speech signal in such a way that the existence of the secret speech isconcealed. In this paper, we develop a steganographic speech coding system based on embeddingcoded secret speech into host public speech coded by the AMR-WB (ITU-T G.722.2) speech coder.For the compression of the secret speech signal, we used the 2.4 kbits/s MELP speech coder. Theembedding process of the secret bit stream is carried out into the split-multistage vectorquantization (S-MSVQ) indices of G.722.2 immittance spectral frequencies (ISF) by modifying themechanism of the S-MSVQ second stage.