Decimation-Whitening Filter in Spectral Band Replication

作者：Hsu Han Wen^*; Liu Chi Min

来源：IEEE Transactions on Audio Speech and Language Processing, 2011, 19(8): 2304-2313.

DOI：10.1109/TASL.2011.2131130

• analytic signal
• bandwidth extension
• high-frequency (HF) reconstruction
• linear prediction
• spectral band replication (SBR)
• whitening

MPEG-4 High-Efficiency Advanced Audio Coding (HE-AAC) has adopted spectral band replication (SBR) to efficiently compress the high-frequency part of the audio. In SBR, linear prediction is applied to low-frequency subbands to suppress tonal components and smooth the associated spectra for replicating to high-frequency bands. Such a tone-suppressing process is referred to as whitening filtering. In SBR, to avoid the alias artifact incurred by spectral adjustment, a complex filterbank instead of real filterbank is adopted. For QMF subbands, this paper demonstrates that the linear prediction defined in the SBR standard results in a predictive bias. A new whitening filter, called the decimation-whitening filter, is proposed to eliminate the predictive bias and provide advantages in terms of noise-to-signal ratio measure, frequency resolution, energy leakage, and computational complexity for SBR.

• 出版日期2011-11