Improved VoIP Real-time Speech Hiding Based on Discrete Cosine Transform

• Main Authors: Yuan-Po Shen, 沈遠博
• Other Authors: Jin-Fu Chang
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/97161432407238237242

碩士 === 國立暨南國際大學 === 電機工程學系 === 103 === Abstract Communication is easy to be eavesdropped as it travels on the Internet. Therefore, steganography is a good solution to protect important Voice over Internet Protocol (VoIP ) conversations. By this mechanism, eavesdroppers may only feel there are some noises in a VoIP call, but will not notice an important secret conversation is hidden in that call. In this thesis, we propose a method for voice hiding in a real-time communication system using the G.711 codec. The proposed method applies Discrete Cosine Transform (DCT) to hide a secret conversation into frequency coefficients which could prevent eavesdropping and resist Regular and Singular (RS) steganalysis. Key words: DCT, G.711, RS steganalysis, Steganography, VoIP