Enhanced Spectral Envelope Coding Scheme Using Inter-frame Correlation for G.729.1

G.729.1 코더에서 프레임 간의 상호상관 관계를 이용한 개선된 스펙트럼 포락 코딩 방법

  • 조근석 (한국과학기술원 전기 및 전자공학과) ;
  • 성종모 (한국전자통신연구원 광대역통신망연구단) ;
  • 한민수 (한국과학기술원 전기및전자공학과) ;
  • 김영일 (경상대학교 공학연구원) ;
  • 정상배 (경상대학교 공학연구원)
  • Published : 2009.12.30

Abstract

This paper describes a new algorithm for encoding spectral envelope in the time domain alias cancellation (TDAC) part of G.729.1. The spectral envelope and modified discrete cosine transform (MDCT) coefficients of the weighted code-excited linear predictive (CELP) coding error in lower-band and the higher-band input signal are encoded in the TDAC part. In order to reduce allocation bits for spectral envelope coding, a new algorithm using sub-band correlation between adjacent frames is proposed. In addition, to improve the quality of decoded signals, two bit allocation strategies using reduced bits from the proposed algorithm are proposed. The performance of the proposed algorithm is evaluated in terms of objective quality and bit reduction rates. Experimental results show that the proposed algorithm increases the quality of sounds significantly.

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