Assembly and C Code of thesis (Real Time Implementation of G.728 Speech Codec using TMS320C5402)





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,





references :

1- Panos E. Papamichalis, “Practical Approaches to Speech Coding “, Prentice-Hall Inc. ,1987.

2-B.S. Atal & R.Remde “A new model of LPC excited for producing natural-sounding speech at low bit rates”, Proc.ICASSP pp.614-617  1982.

3-Jason P. Woodard , “Digital Speech Coding” , Mini-Thesis ,  Department of  Electronics & Computer Science, University of Southampton, Jun 1994.

4-J.Makhoul “Linear Prediction: A Tutorial Review ” Proc. IEEE,vol 63, No.4,pp.561-580  Apr 1975.

5- Kondoz A.M,” Digital Speech , Coding of low bit rate communication Systems”,Chichester Wiley 2000

6- Chen,Cox & Lin,”A Low-Delay CELP Coder for the CCITT 16 kb/s Speech Coding Standard”,IEEE Jour. On Selected Area in Comm.,vol.10,no.5 ,June 92.

7- L.Hanzo,A.Somerville & Jason P. Woodard, “Voice Compression and Communication”,IEEE series on Digital & Mobile,2001

8- Schroeder & Atal ,”Code-Excited linear Prediction (CELP):High quality speech at very low bit rates”,IEEE,ICASSP,pp.937-940,1985.

9- ITU,”Coding of Speech at 16 kbps using Low-Delay Code Excited Linear Prediction “, ITU (CCITT) Recommendation G.728, 1992.

10- ITU,” G.728 Annex G , 16 kbps Fixed Point specification “, 11/94.

11- TI, “TMS320C54x Assembly language tools user guide “,    June 2001.

12- TI, ” TMS320C54x DSP reference set, volume 1: CPU”, spru131,

13- TI, ” TMS320C54x DSP reference set, volume 2: Mnemonic instruction set”,   spru172, .

14- TI, “Code Composer user guide”,spru 328,

15- TI, “C5402 DSK user guide” ,

16- TI,” DSP product tree” ,

17- TCTS Lab,” The LD-CELP at 16kb/s (ITU-T G.728)”, Coding research group homepage,

18- ITU,”G.728 Annex H:variable bit rate LD-CELP operation mainly for DCME at rates less than 16 kb/s”,5/99.

19- DCS G.728 C54x Vocoder,                                                                                            algorithm,       EAB728D36C3C916E862569F200542A92.



There are no reviews yet.

Be the first to review “Assembly and C Code of thesis (Real Time Implementation of G.728 Speech Codec using TMS320C5402)”