Secure steganography in audio using inactive frames of VoIP streams

摘要

Steganography is a data hiding process in which information is secured, while transferring data from sender to receiver. In audio steganography, encoding process is carried out through inactive frames of low bit rate audio streams by performing iLBC (Internet Loy Bit rate Codec). This methodology can be used in applications such as VoIP(Voice Over Internet Protocol), streaming audio archival and messaging. Traditionally data embedding is carried out in the inactive frames rather than the active frame of streams; that is inactive frame has large embedding capacity. In addition VAD (Voice Activity Detection) algorithm is used for detecting inactive frames. The concealment of analysis is encoded by iLBC that supports two basic frame lengths giving a bit-rate of 13.3 kbps with an encoding frame length of 30 ms and 15.2 kbps with an encoding frame length of 20 ms. To enhance security in steganography PCC (Parabolic Curve Cryptography) algorithm is implemented.