Title
Harmonic enhancement in low bitrate audio coding using an efficient long-term predictor
Abstract
This paper proposes audio coding using an efficient long-term prediction method to enhance the perceptual quality of audio codecs to speech input signals at low bit-rates. The MPEG-4 AAC-LTP exploited a similar concept, but its improvement was not significant because of small prediction gain due to long prediction lags and aliased components caused by the transformation with a time-domain aliasing cancelation (TDAC) technique. The proposed algorithm increases the prediction gain by employing a deharmonizing predictor and a long-term compensation filter. The look-back memory elements are first constructed by applying the de-harmonizing predictor to the input signal, then the prediction residual is encoded and decoded by transform audio coding. Finally, the long-term compensation filter is applied to the updated look-back memory of the decoded prediction residual to obtain synthesized signals. Experimental results show that the proposed algorithm has much lower spectral distortion and higher perceptual quality than conventional approaches especially for harmonic signals, such as voiced speech.
Year
DOI
Venue
2010
10.1155/2010/939542
EURASIP Journal on Advances in Signal Processing
Keywords
DocType
Volume
long prediction lag,audio codecs,audio coding,efficient long-term prediction method,efficient long-term predictor,long-term compensation filter,de-harmonizing predictor,prediction gain,harmonic enhancement,decoded prediction,small prediction gain,proposed algorithm,low bitrate audio coding
Journal
2010,
Issue
ISSN
Citations 
1
1687-6180
1
PageRank 
References 
Authors
0.48
8
4
Name
Order
Citations
PageRank
Jeongook Song111.16
Chang-Heon Lee253.38
Hyen-O Oh3276.04
Hong-Goo Kang419048.76