September 22-25, 1997
The human auditory system is insensitive to phase information of the speech signal. By taking advantage of this fact data such as the transcript, some keywords, and copyright information can be embedded into the speech signal by altering the phase in a predefined manner. In this paper, an all-pass filtering based data embedding scheme is developed for speech signals. Since all-pass filters modify only the phase without effecting the magnitude response they are employed to diffuse data into the speech signal by filtering different portions of the speech signal with different all-pass filters. The embedded data can be retrieved by tracking the zeros of the all-pass filters.
Bibliographic reference. Yardimci, Yasemin / Cetin, A. Enis / Ansari, Rashid (1997): "Data hiding in speech using phase coding", In EUROSPEECH-1997, 1679-1682.