• Title/Summary/Keyword: 새로운 역할

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Science Trends

  • Hyeon, Won-Bok
    • The Science & Technology
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    • no.11 s.414
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    • pp.110-111
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    • 2003
  • 홍콩과학기술대학, 홍콩중국대학과의 통합 갈등/ 균류의 새로운 역할 발견/ '화학 공장'으로 바뀐 WTC 건물/ UN, 서태평양 연어 보존사업 착수

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Efficient Codebook Search Method for AMR Wideband Speech Codec (광대역 AMR 음성 압축기를 위한 효율적인 코드북 검색 방법)

  • 김윤희;박호종
    • The Journal of the Acoustical Society of Korea
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    • v.22 no.4
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    • pp.308-314
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    • 2003
  • Wideband speech communications with 7㎑ bandwidth can provide high-quality speech services that are almost impossible with current narrow-band speech communications with 3.4 ㎑ bandwidth, and AMR wideband codec was recently developed for these services. The performance of AMR wideband codec is excellent due to its wideband information and partially to ACELP structure, but it requires high computational complexity especially in codebook search. In this paper, to solve this problem, an efficient codebook search method for AMR wideband codec is proposed. The proposed method first determines the coarse initial codevector, then improves the performance of codevector by replacing a poor pulse in codevector with better one iteratively. Simulations show that AMR wideband codec with proposed codebook search method has higher performance with much less computational cost than conventional AMR wideband codec.