Hybrid Speech Steganography System using SS-RDWT with IPDP-MLE approach

Abstract

Generally, defence applications need the high secured communication over the channel. Most of the defence-based communications are performed through the audio and speech signals in the secured environment. To provide security to these digital media and speech signals, considerably advanced technologies are implementing in the last two decades. However, digital media transmission over the secured and unsecured channels creating several big problems in defence data transfer applications due to equivalence of works, plasticity, ease of replication and unauthorized use in the digital format of data. The possible solution is to secure digital media by cover writing the speech signals by using speech steganography, so the digital media effectively hid over the speech. To overcome these problems, this article is mainly focussing on securing the speech and message through the hybrid speech steganography approach. This system is implemented with the spread spectrum-based redundant discrete wavelet transform (SS-RDWT) with additional pause removal properties. The input cover speech signal contains a larger size, and system requires the higher power usage, computational time and extra storage capacity. Thus, an intelligent pause detection protocol (IPDP) is implemented to remove the pauses and reduces the size of the speech signal. The performance of the IPDP protocol is improved by the maximum likelihood estimation (MLE) procedure. Finally, SS-RDWT speech steganography is implemented along with the IPDP-MLE-based pause removal mechanism. The simulation results show that the proposed method gives better performance against various noise attacks and improved the robustness, imperceptibility and security as compared to the conventional approaches.