Improved Synthesis Method of Negative Inter-channel Correlation Parameter Based on Anti-phase Primary Component

Dong-il Hyun; Seok-Pil Lee; Young-cheol Park; Dae Hee Youn

doi:10.7776/ASK.2012.31.6.410

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2012 Vol.31, Issue 6 Preview Page

Improved Synthesis Method of Negative Inter-channel Correlation Parameter Based on Anti-phase Primary Component 반위상 주요성분에 기반을 둔 개선된 음수 채널간 상관도 파라미터 합성 기법

31 August 2012. pp. 410-418

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Abstract

Parametric stereo(PS) and MPEG surround(MPS) are major spatial audio coding(SAC) tools. In this paper, the problem of the inter-channel correlation(ICC) synthesis in the conventional SAC is analyzed. Conventional methods assume that ambient components mixed to two output channels are anti-phased, while the primary components are assumed to be in-phased. This assumption can cause excessive ambient mixing for a negative-valued ICC. As a remedy to this problem, we propose a new ICC synthesis method based on an assumption that the primary components are anti-phased each other for a negative ICC. The proposed method is also applied to the approximation which works in practice. The performance of the proposed method was evaluated by computer simulations and the subjective listening tests verified that the proposed method is effective in not only headphones but also loudspeakers playback.

Keywords

Parametric Stereo

MPEG Surround

Spatial Audio Coding

Inter-Channel Correlation

Anti-Phase

파라메트릭 스테레오와 MPEG 서라운드는 대표적인 공간 오디오 부호화 기법이다. 본 논문에서는 기존의 공간 오디오 부호화 기법에서 채널간 상관도 합성의 문제점을 분석하였다. 기존의 방법에서는 출력신호에 합성되는 주요성분들은 서로 동위상 관계에 있는 반면 잔향성분들은 서로 반위상 관계에 있다고 가정하고 있다. 음수 채널간 상관도에 대해서 이러한 가정은 잔향성분을 과도하게 포함하도록 하는 문제점을 야기할 수 있다. 이에 대한 해결책으로 음수 채널간 상관도를 가지는 경우에 대해서는 주요성분들이 반위상 관계에 있다는 가정을 기반으로 새로운 채널간 상관도 합성 기법을 제안하였다. 제안된 기법은 실제 부호화 및 복호화기에서 동작하는 근사화 과정에도 적용되었다. 컴퓨터 시뮬레이션을 통하여 제안된 기법의 성능을 평가하였으며 주관적 청취 실험을 통하여 제안된 방법이 헤드폰 환경뿐만 아니라 스피커 환경에서도 효과적으로 동작함을 검증하였다.

키워드

파라메트릭 스테레오

MPEG 서라운드

공간 오디오 부호화

채널간 상관도

반위상

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Information

Publisher :The Acoustical Society of Korea
Publisher(Ko) :한국음향학회
Journal Title :The Journal of the Acoustical Society of Korea
Journal Title(Ko) :한국음향학회지
Volume : 31
No :6
Pages :410-418
Received Date : 2012-02-29
Revised Date : 2012-05-09
Accepted Date : 2012-07-11
DOI :https://doi.org/10.7776/ASK.2012.31.6.410

The Journal of the Acoustical Society of KoreaISSN:1225-4428(Print) 2287-3775(Online)한국음향학회

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