The G.729 Voice Codec On The Dsp Real-time Implementation

The rapidly developing DSP technology has more and more become a powerful tool in the field of speech processing, which makes it possible to implement all kinds of complex algorithms in real time. The G.729 speech codec (encoder and decoder) is an algorithm recommendation for the coding of speech signals at 8kbitls bit rate using Conjugate-Structure Algebraic-Code-Excited Linear-Predication (CS-ACELP), which was approved by 1W (International Telecommunication Union) Study Group 15 on the 19th of March 1996. 1W G.729 has been widely used in the field of multimedia communication. digital cellular communication system, LP network phone and so on. In this paper, the principle of this algorithm and its implementation on a single chip of fixed point TMS320LC549 DSP are studied, including the structure of hardware, software and the key technology in the process of implementation. The main aspects dealt with this paper are structured as follows:1.Introduction on the current speech compression technology and the demand ofimplementation of various kinds of speech compression algorithms in real time using DSP technology.2.Introduction on the digital model of speech signal generation and the principle of the Linear Prediction Analysis-by-Synthesis (LPAS) coding technology which is based on the principle of speech signal generation.3.Studying the algorithm principle of the G.729 vocoder based on the structure ofLPAS.4.Studying the makeup of the hardware platform, the designation of the system software and the software optimization based on the demand of (1.729 algorithm and real time.5.Analyzing and evaluating the performance of the whole system using the Code Composer Studio (CCS) software. The testing result is given.