Enhancement of Speech Quality in Telephony Communications by Steganography

Abstract

Steganography can transmit supplementary data without changing conventional data formats. The concept of high value-added communications is drawn from this advantage of steganography. As a specific application of the concept, this chapter describes two topics about the enhancement of the speech quality in telephony communications by steganography. A packet loss concealment technique and a band extension technique are explained. These techniques employ steganography for transmitting side information for improving the performance of signal processing. In addition, this chapter describes an efficient steganography technique devised for G.711, the most common codec for telephony speech standardized by ITU-T. The proposed technique, named selective LSB replacement technique, outperforms the conventional one in order to decrease the degradation caused by embedding side information into speech data by steganography.