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http://dx.doi.org/10.7776/ASK.2010.29.1.062

Enhanced Adjustment Strategy of Masking Threshold for Speech Signals in Low Bit-Rate Audio Coding  

Lee, Chang-Heon (연세대학교 전기전자공학과)
Kang, Hong-Goo (연세대학교 전기전자공학과)
Publication Information
The Journal of the Acoustical Society of Korea / v.29, no.1, 2010 , pp. 62-68 More about this Journal
Abstract
This paper proposes a new masking threshold adjustment strategy to improve the performance for speech signals in low bit-rate audio coding. After determining formant regions, the masking threshold is adjusted by using the energy ratio of each sub-band to the average energy of each formant. More quantization noises are added to the bands that have relatively large energy, but less distortion is allowed in spectral valley regions by allocating more bits, which reflects the concept of perceptual weighting widely used in speech coding. From the results of objective speech quality measure, we verified that the proposed method improves quality for the speech input signals compared to the conventional one.
Keywords
Enhanced AacPlus; HE-AAC; Psychoacoustic Model; Masking Threshold; Perceptual Weighting; Audio Coding; Speech Coding;
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