DOI QR코드

DOI QR Code

An Algorithm on Improving a Pitch Searching by Energy Compensation in a Frame for Vocoder

보코더에서 프레임별 에너지 보상에 의한 피치검색 성능 개선에 관한 연구

  • Baek, Geum-Ran (Dept. of Information and Telecommunication, Soongsil University) ;
  • Min, So-Yeon (Dept. of Information&Communication Seoil University) ;
  • Bae, Myung-Jin (Dept. of Information and Telecommunication, Soongsil University)
  • 백금란 (숭실대학교 정보통신학과) ;
  • 민소연 (서일대학교 정보통신과) ;
  • 배명진 (숭실대학교 정보통신학과)
  • Received : 2012.05.29
  • Accepted : 2012.07.12
  • Published : 2012.07.31

Abstract

It is important to search a pitch for vocoder. The major drawback to vocoders is their large computational requirements in searching a pitch and a codebook. In this paper, a simple method is proposed to improve the pitch searching process in the pitch filter almost without degradation of quality. The period of speech signal is emphasized by using Dual Pulse technique, the same type of autocorrelation method, in pitch search. Sometimes the incorrect pitch can be obtained by halving, doubling and trifling, To solve it, before searching a pitch, we estimate energy rate in a frame and compensate envelop of signal with it. By using the proposed algorithm in pitch search, its required computation are reduced and searching pitch is improved.

Keywords

Pitch search;Autocorrelation;Dual pulse technique

References

  1. M. J. Bae, Digital Speech Coding, p17-29, p30-48, pp49-68 Dongyoung, 1996.
  2. J. S. Han, Speech Processing, Osung Media, pp.5- pp7, pp103. 2003년.
  3. M. J. Bae, S. H. Lee, Digital Speech Analysis, p123- Dongyoung, 1996.
  4. L. R. Rabiner, R. W. Schafer, Digital Processing of Speech Signal, pp.131-149.
  5. M. J. Bae, "On a Performance Comparison of Pitch Search Algorithms by using a Correlation Properties for the CELP Vocoder", In ASK, the proceeding Vol. 11, pp. 165-171, 2004.
  6. J. K. Kim and M. J. Bae, "A study of pitch extraction method by using harmonics peak-fitting in speech spectrum", In ASK, Proceedings of ICSP 2001, Vol, 1, pp. 617-622, 2001.
  7. A. M. Kondoz, Digital Speech coding for low bit rate communications systems, John Wiley & Sons, new York, 2004.
  8. JooHun Lee, MyungJin Bae, SouGil Ann, "A Fast Pitch Searching Algorithm Using Correlation Characteristics in CELP Vocoder", The Journal of ASK, Vol. 13. No. 2E, 1994.
  9. Wang-Rae Jo, Seong-Young Choi, MyungJin Bae, "A Study on Pitch Search Time Reduction of G.723.1 Vocoder by Improved Hybrid Domain Cross-correlation" Trans.KIEE.Vol.59,No.12,DEC,2010.
  10. JaeOk Bae, KiChun Han, JinJong Cha and MyungJin Bae, "On a Fast Searching of the Random Codebook using the Searching Technique of the Regular Pulse Excitation," International Conference on Speech Processing, Proceedings of ICSP'97, pp.281-286, August 26-28, 1997.