Real-time Implementation of Variable Transmission Bit Rate Vocoder Integrating G.729A Vocoder and Reduction of the Computational Amount SOLA-B Algorithm Using the TMS320C5416

TMS320C5416을 이용한 G.729A 보코더와 계산량 감소된 SOLA-B 알고리즘을 통합한 가변 전송율 보코더의 실시간 구현

  • 함명규 (숭실대학교 정보통신공학과) ;
  • 배명진 (숭실대학교 정보통신공학과)
  • Published : 2003.11.01

Abstract

In this paper, we real-time implemented to the TMS320C5416 the vocoder of variable bit rate applied the SOLA-B algorithm by Henja to the ITU-T G.729A vocoder of 8kbps transmission rate. This proposed method using the SOLA-B algorithm is that it is reduced the duration of the speech in encoding and is played at the speed of normal by extending the duration of the speech in decoding. At this time, we bandied that the interval of cross correlation function if skipped every 3 sample for decreasing the computational amount of SOLA-B algorithm. The real-time implemented vocoder of C.729A and SOLA-B algorithm is represented the complexity of maximum that is 10.2MIPS in encoder and 2.8MIPS in decoder of 8kbps transmission rate. Also, it is represented the complexity of maximum that is 18.5MIPS in encoder and 13.1MIPS in decoder of 6kbps, it is 18.5MIPS in encoder and 13.1MIPS in decoder of 4kbps. The used memory is about program ROM 9.7kwords, table ROM 4.5kwords, RAM 5.1 kwords. The waveform of output is showed by the result of C simulator and Bit Exact. Also, for evaluation of speech quality of the vocoder of real-time implemented variable bit rate, it is estimated the MOS score of 3.69 in 4kbps.

References

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