• Journal of Broadcast Engineering
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• v.16 no.5
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• pp.714-721
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• 2011

MPEG audio uses the masking effect, high frequency component synthesis based on spectral band replication, and channel expansion based on parametric stereo for efficient compression of audio signals. In this paper, we present an overview of the state-of-the-art channel expansion technology in MPEG audio. We also present technical overviews and application examples to broadcasting services for HE-AAC v.2, MPEG Surround, spatial audio object coding (SAOC), and unified speech and audio coding (USAC) which are MPEG audio codecs based on the channel expansion technology.

• ETRI Journal
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• v.38 no.5
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• pp.829-837
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• 2016

In this paper, we introduce extension tools for MPEG Surround, which were recently adopted as MPEG-H 3D Audio tools by the ISO/MPEG standardization group. MPEG-H 3D Audio is a next-generation technology for representing spatial audio in an immersive manner. However, considerably large numbers of input signals can degrade the compression performance during a low bitrate operation. The proposed extension of MPEG Surround was basically designed based on the original MPEG Surround technology, where the limitations of MPEG Surround were revised by adopting a new coding structure. The proposed MPEG-H 3D Audio technologies will play a pivotal role in dramatically improving the sound quality during a lower bitrate operation.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.49-52
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• 2008

This paper briefly introduces the current status of MPEG Audio Subgroup activities for standardizing a new audio coding technologies. Currently MPEG Audio Subgroup focused on spatial audio coding tools for compressing multiple audio objects and unified coding tools for presenting the consistence performance on speech and audio signal at the same time. Also a new MAF (MPEG Application Format) for interactive music was introduced at the 84th MPEG meeting.

• The Journal of the Acoustical Society of Korea
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• v.28 no.7
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• pp.630-639
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• 2009

This paper introduces MPEG SAOC (Spatial Audio Object Coding) that has been standardized in MPEG audio subgroup. MPEG SAOC is a trendy parametric coding technology conceptually similar to PS (Parametric Stereo) and the MPEG Surround. SAOC especially parameterizes and codes the spatial information for the object signals comprising a downmixed audio scene and thus lets users render one's preferred scene in an interactive manner.

• Broadcasting and Media Magazine
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• v.4 no.1
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• pp.62-79
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• 1999

In this survey paper the emerging MPEG-4 audio technology is discribed In the previous MPEG-1 and the MPEG-4 audio words, only the natural audio and the speech coding techniques were the standadization objects But in the MPEG-4 audio standadization, not only the natural audio and the speech coding, but also the structured audio and the synthetic speech techniques are inclued, The purpose of this expansion can be summarized as the preparation for the versatile high-quality multimedia services supposed emerge in the 21st century.

• Journal of Korea Multimedia Society
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• v.10 no.8
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• pp.958-966
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• 2007

In this paper, we implement a sound-enhanced MPEG-1 audio decoder on embedded OS Platform. Low bit rate lossy audio codecs such as MP3, OGG, and AAC for mitigating the problems in storage space and network bandwidth suffer a major common problem such as a loss of high frequency fidelity of audio signal. This high frequency loss will reproduce only a band-limited low-frequency part of audio in the standard CD-quality audio. In order to overcome this problem, we embedded a sound enhancement algorithm into the MPEG-1 audio decoder and then the algorithms optimized according to the characteristic of the MPEG-1 audio layer I, II, III were implemented on an embedded OS platform. From the experimental results with spectrum analysis and listening test, we confirm the superiority of the proposed system compared to the standard MPEG-1 audio decoder.

• The Journal of the Acoustical Society of Korea
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• v.16 no.4
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• pp.64-70
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• 1997

This paper is aimed to propose a new wavelet audio signal coding scheme which reduces the complexity of well-known MPEG(Moving Picture Expert Group)-Audio. The filters of MPEG0audio apply subband technique on the 16-bits PCM audio to aquire bitstream of subband sample using dynamic bit allocation. If we use the wavelet coefficients instead of subband samples and 6 bands which is less than 32 bands of MPEG-audio, the complexity can be reduced. A new audio signal compression algorithm in this paper is based on wavelet transform and the proposed algorithm is compared with MPEG-audio. At the bitrate of 256kbps, the proposed algorithm maintains the CD(Compact-disc) quality. We were able to reduce the about 40% of complexity at encoder and about 70% at decoder.

• Proceedings of the IEEK Conference
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• 2000.06b
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• pp.181-184
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• 2000

In this paper, we described a design of the input buffer system for efficiently dealing with MPEG audio bitstream to demux header and side information, audio data. In order to overcome the limitations of fixed-word manipulation in bitstream demuxing, we proposed a new variable length bit retrieval system with FSM sequencer supporting MPEG audio frame format, and serial buffer demuxing audio stream, FIFO circular buffer including header and side information.

• Electronics and Telecommunications Trends
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• v.37 no.3
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• pp.52-63
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• 2022

Immersive media, also known as spatial media, has become essential with the decrease in face-to-face activities in the COVID-19 pandemic era. Teleconference, metaverse, and digital twin have been developed with high expectations as immersive media services, and the demand for hyper-realistic media is increasing. Under these circumstances, MPEG-I Immersive Media is being standardized as a technologies of navigable virtual reality, which is expected to be launched in the first half of 2024, and the Audio Group is working to standardize the immersive audio technology. Following this trend, this article introduces the trend in MPEG-I immersive audio standardization. Further, it describes the features of the immersive audio rendering technology, focusing on the structure and function of the RM0 base technology, which was chosen after evaluating all the technologies proposed in the January 2022 "MPEG Audio Meeting."

• Journal of Broadcast Engineering
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• v.25 no.5
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• pp.723-733
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• 2020

In this paper, MPEG-I Immersive Audio Standardization and related trends are presented. MPEG-I Immersive Audio, which is under the development of standard documents at the exploration stage, can make a user interact with a virtual scene in 6 DoF manner and perceive sounds realistic and matching the user's spatial audio experience in the real world, in VR/AR environments that are expected as killer applications in hyper-connected environments such as 5G/6G. In order to do this, MPEG Audio Working Group has discussed the system architecture and related requirements for the spatial audio experience in VR/AR, audio evaluation platform (AEP) and encoder input format (EIF) for assessing the performance of submitted proponent technologies, and evaluation procedures.