Superwideband Bandwidth Extension Using Normalized MDCT Coefficients for Scalable Speech and Audio Coding

A bandwidth extension (BWE) algorithm from wideband to superwideband (SWB) is proposed for a scalable speech/audio codec that uses modified discrete cosine transform (MDCT) coefficients as spectral parameters. The superwideband is first split into several subbands that are represented as gain parame...

Full description

Saved in:
Bibliographic Details
Main Authors: Young Han Lee, Seung Ho Choi
Format: Article
Language:English
Published: Wiley 2013-01-01
Series:Advances in Multimedia
Online Access:http://dx.doi.org/10.1155/2013/909124
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850121028507795456
author Young Han Lee
Seung Ho Choi
author_facet Young Han Lee
Seung Ho Choi
author_sort Young Han Lee
collection DOAJ
description A bandwidth extension (BWE) algorithm from wideband to superwideband (SWB) is proposed for a scalable speech/audio codec that uses modified discrete cosine transform (MDCT) coefficients as spectral parameters. The superwideband is first split into several subbands that are represented as gain parameters and normalized MDCT coefficients in the proposed BWE algorithm. We then estimate normalized MDCT coefficients of the wideband to be fetched for the superwideband and quantize the fetch indices. After that, we quantize gain parameters by using relative ratios between adjacent subbands. The proposed BWE algorithm is embedded into a standard superwideband codec, the SWB extension of G.729.1 Annex E, and its bitrate and quality are compared with those of the BWE algorithm already employed in the standard superwideband codec. It is shown from the comparison that the proposed BWE algorithm relatively reduces the bitrate by around 19% with better quality, compared to the BWE algorithm in the SWB extension of G.729.1 Annex E.
format Article
id doaj-art-6250465e0f944d69a2e5fa3e7b44de49
institution OA Journals
issn 1687-5680
1687-5699
language English
publishDate 2013-01-01
publisher Wiley
record_format Article
series Advances in Multimedia
spelling doaj-art-6250465e0f944d69a2e5fa3e7b44de492025-08-20T02:35:12ZengWileyAdvances in Multimedia1687-56801687-56992013-01-01201310.1155/2013/909124909124Superwideband Bandwidth Extension Using Normalized MDCT Coefficients for Scalable Speech and Audio CodingYoung Han Lee0Seung Ho Choi1Speech Team, Future IT Convergence Laboratory, LG Advanced Research Institute, Seoul 137-724, Republic of KoreaDepartment of Electronic and IT Media Engineering, Seoul National University of Science and Technology, Seoul 139-743, Republic of KoreaA bandwidth extension (BWE) algorithm from wideband to superwideband (SWB) is proposed for a scalable speech/audio codec that uses modified discrete cosine transform (MDCT) coefficients as spectral parameters. The superwideband is first split into several subbands that are represented as gain parameters and normalized MDCT coefficients in the proposed BWE algorithm. We then estimate normalized MDCT coefficients of the wideband to be fetched for the superwideband and quantize the fetch indices. After that, we quantize gain parameters by using relative ratios between adjacent subbands. The proposed BWE algorithm is embedded into a standard superwideband codec, the SWB extension of G.729.1 Annex E, and its bitrate and quality are compared with those of the BWE algorithm already employed in the standard superwideband codec. It is shown from the comparison that the proposed BWE algorithm relatively reduces the bitrate by around 19% with better quality, compared to the BWE algorithm in the SWB extension of G.729.1 Annex E.http://dx.doi.org/10.1155/2013/909124
spellingShingle Young Han Lee
Seung Ho Choi
Superwideband Bandwidth Extension Using Normalized MDCT Coefficients for Scalable Speech and Audio Coding
Advances in Multimedia
title Superwideband Bandwidth Extension Using Normalized MDCT Coefficients for Scalable Speech and Audio Coding
title_full Superwideband Bandwidth Extension Using Normalized MDCT Coefficients for Scalable Speech and Audio Coding
title_fullStr Superwideband Bandwidth Extension Using Normalized MDCT Coefficients for Scalable Speech and Audio Coding
title_full_unstemmed Superwideband Bandwidth Extension Using Normalized MDCT Coefficients for Scalable Speech and Audio Coding
title_short Superwideband Bandwidth Extension Using Normalized MDCT Coefficients for Scalable Speech and Audio Coding
title_sort superwideband bandwidth extension using normalized mdct coefficients for scalable speech and audio coding
url http://dx.doi.org/10.1155/2013/909124
work_keys_str_mv AT younghanlee superwidebandbandwidthextensionusingnormalizedmdctcoefficientsforscalablespeechandaudiocoding
AT seunghochoi superwidebandbandwidthextensionusingnormalizedmdctcoefficientsforscalablespeechandaudiocoding