Data Hiding for Audio Signals That Are Robust with Respect to Air Transmission and a Speech Codec
Akira Nishimura · 2008
A technique for hiding data in audio signals using subband amplitude modulation was evaluated by a computer simulation in terms of robustness with respect to cascaded disturbances of reverberations, background noises, and the speech codec. Speech signals from 22 speakers and signals from 100 pieces of music in various genres were served to the host audio data. Computer simulation showed that the speech and music signals with background noise and reverberations were able to transmit at least 80% of embedded data at 8 bps after encoding and decoding using the AMR speech codec at a bitrate of 12.2 kbps. Objective measurement of sound quality degradation induced by data hiding was performed by PESQ and PEAQ algorithms. The average PESQ score for speech signals approximately corresponded to the subjective evaluation of 'fair'. The average PEAQ score for the music signals was slightly degraded from the subjective difference grade of 'slightly annoying'.