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


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.


Pitch search;Autocorrelation;Dual pulse technique


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