Secure speech communication has been of great significance in civil, commercial and particularly in military communication systems. Speech scramblers play a major role in these systems. Transform-domain, specially, DCT (Discrete Cosine Transform) based encryption of speech signals has often been a preferable choice for researchers. In such systems, besides security, removal of redundant information and execution speed of the algorithms have also been main focus of research and exploration. In this book, these three attributes, redundancy, speed and security are envisaged by exploiting ITU-T...