G.728 speech codec is a low delay ITU standard codec which could provide toll quality speech in 16kb/s. It is specially designed for delay-sensitive applications like satellite telephony, Internet, and mobile networks.
In this thesis, real-time implementation of full duplex G.728 encoder and decoder on TMS320C5402 is presented. Using a combinatorial technique for TMS programming, the programming time and complexity have been decreased to 30% compared with traditional assembly programming. First, a fixed point simulation of the codec algorithm has been programmed in C and it is compiled to assembly using CCS (Code Composer Studio) and manually optimized. Then some of the critical functions regarding MIPS, have been programmed in assembly for achieving real-time implementation. Finally, implementation results have been presented.
Keywords: Speech Coding & Compression, Real Time Implementation, DSP,
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