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http://dx.doi.org/10.7776/ASK.2009.28.2.148

Enhancement of SBR for Speech Signal Using Adaptive Noise Floor Level  

Lee, Se-Won (광운대학교 전자공학과)
Oh, Seoung-Jun (광운대학교 전자공학과)
Ahn, Chang-Beom (광운대학교 전자공학과)
Lee, Tae-Jin (한국전자통신연구원 방통미디어연구부)
Kang, Kyoung-Ok (한국전자통신연구원 방통미디어연구부)
Park, Ho-Chong (광운대학교 전자공학과)
Publication Information
The Journal of the Acoustical Society of Korea / v.28, no.2, 2009 , pp. 148-154 More about this Journal
Abstract
In audio coding, SBR technology synthesizes the high-bands using patched time-frequency information from low-bands and the correction parameters, Since SBR transmits only correction parameters for high-bands, it provides a low-rate coding of high-bands, and is used as a core module of MPEG-4 HE-AAC, SBR was originally designed for audio signal and its performance for speech signal tends to decrease, and the major reason is an excessive noise floor in high-bands which is caused by incorrect tonality computation, In this paper, a new method to determine noise floor level in an adaptive fashion according to the speech characteristics is proposed in order to solve the problem of SBR for speech signal, The proposed method maintains the compatibility with the standard SBR, and the subjective performance evaluation shows that the proposed method improves the SBR performance especially for male speech signal compared with the standard SBR.
Keywords
SBR; HE-AAC; Noise floor level; Pitch frequency; Linear prediction;
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  • Reference
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