• Proceedings of the Korea Multimedia Society Conference
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• 2002.11b
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• pp.771-775
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• 2002

멀티미디어 데이터의 효과적인 네트워크 전송에 대한 연구와 투자가 계속적으로 증가하고 있다. 본 논문에서는 실시간 전송 프로토콜인 RTP(Real-time Transfer Protocol)를 기반으로 MPEG 오디오 데이터를 실시간 전송하기 위한 PAD(Packet Assembler/Disassembler) 모듈을 설계, 구현하였다. RTP 기반 MPEG 오디오의 PAD 구현 방법은 MPEG 오디오의 계층에 관계없이 전송하는 방법과 MPEG Layer-3에 특화된 방법 등의 두 가지 방법이 있으며, 본 논문에서는 범용성을 중시하여 전자의 방식을 채택, 구현하였다. 구현한 PAD 모듈은 MPEG-1 및 MPEG-2 오디오 포맷을 지원한다.

• Proceedings of the Korea Multimedia Society Conference
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• 2001.06a
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• pp.57-61
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• 2001

MPEG-4 컨텐츠는 다양한 사용자 상호작용에 의하여 장면과 객체의 재생 시간이 동적으로 변화하는 특징이 있다. 본 논문에서는 MPEG-4 컨텐츠를 저작할 때, 사용자 상호작용에 의하여 변화하는 시간 관계에 대한 제약 조건을 모델링한다. 또한 모델링된 시간 제약 모델에 기반한 MPEG-4 컨텐츠 저작 시스템인 MPEG-4 Studio 에 대하여 기술한다. 이 MPEG-4 Studio는 사용자가 저작한 시간 제약에 딸라 MPEG-4 컨텐츠를 재생하는 중요한 연구이다.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10b
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• pp.502-504
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• 2003

MPEG-4 컨텐츠는 데스크 탑 PC 와 같은 유선 환경은 물론 PDA나 휴대폰 등 다양한 이동 단말기 환경에서도 압축된 MPEG-4 컨텐츠의 QoS를 보장하면서 제공받을 수 있어야 한다. 그러므로 특정 단말기에 적합한 MPEG-4 컨텐츠의 제공을 가능하게 하기 위한 적응성 기술의 개발은 매우 중요한 일이다. 이 논문에서는 PDA의 MPEG-4 재생기에 자동으로 적응하여 MPEG-4 컨텐츠가 재생되도록 적응성을 지원하는 MPEG-4 컨텐츠 저작 기법을 소개한다.

• Journal of KIISE:Computing Practices and Letters
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• v.9 no.5
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• pp.509-520
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• 2003

In this paper, we developed a new and robust algorithm for a practical and very efficient MPEG-4 video coding. The MPEG-4 video group has developed the video Verification Model(VM) which evolved through time by means of core experiments. And in the standardization process, MS-FDAM was developed based on the standard document of ISO/IEC 14496-2 and VM as a reference MPEG-4 coding system. But MS -FDAM has drawbacks in practical MPEG-4 coding and it does not have the VOP extraction functionality. In this research, we implemented a preprocessing system for a real-time input and the VOP extraction for a practical content-based MPEG-4 video coding and also implemented the motion detection to achieve the high compression rate of 180:1.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.6B
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• pp.1060-1067
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• 2000

MPEG-4 visual coding is an object-based system. The current video coding standards, H.261, MPEG-1, and MPEG-2 encode frame by frame. On the other hand, MPEG-4 separately encodes several objects, such as video objects and audio objects, in the same frame. Each transmitted object is decoded and composed in one frame. Shape coding is a process of coding visual objects in a frame. In this paper we present conformance test method for MPEG-4 shape decoders. This paper reviews the basic shape decoding standard, and proposes conformance test methods for BAB type decoder, and CAE decoder for intra and inter VOPs. Our test generates all possible cases of shape motion vector difference and context.

• Journal of Korea Multimedia Society
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• v.10 no.2
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• pp.170-178
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• 2007

In restricted resources based on mobile environment, we can use an embedded database technology for management of MPEG-7 data. At this time, some XML clustering methods can be used. But, to improve the performance efficiency better, a new clustering method is need to store effective MPEG-7 document. In this paper, we have designed and implemented a MPEG-7 document management system to store MPEG-7 document effectively in mobile device such as PDA. The system used the 버클리 DB XML as a native embedded XML database system based on the clustering method of MPEG-7 data.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.47 no.3
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• pp.87-95
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• 2010

Portable multi-media products which can service the highest audio-quality by using lossless audio codec has been released and the international lossless codecs, MPEG-4 audio lossless coding(ALS) and MPEG-4 scalable lossless coding(SLS), were standardized by MPEG in 2006. The simple profile of MPEG-4 ALS, it supports up to stereo, was defined by MPEG in 2009. The lossless audio codec should have low-complexity in stereo to be widely used in portable multi-media products. But the previous researches of MPEG-4 ALS have focused on an improvement of compression ratio, a complexity reduction in multi-channels coding, and a selection of linear prediction coefficients(LPCs) order. In this paper, the complexity and compression ratio of MPEG-4 ALS encoder is analyzed in simple profile of MPEG-4 ALS, the method to reduce a complexity of MPEG-4 ALS encoder is proposed. Based on an analysis of complexity of MPEG-4 ALS encoder, the complexity of short-term prediction filter of MPEG-4 ALS encoder is reduced by using the low-complexity filter that is proposed in previous research to reduce the complexity of MPEG-4 ALS decoder. Also, we propose a joint coding decision method, it reduces the complexity and keeps the compression ratio of MPEG-4 ALS encoder. In proposed method, the operation of joint coding is decided based on the relation between cross-correlation of residual and compression ratio of joint coding. The performance of MPEG-4 ALS encoder that has the method and low-complexity filter is evaluated by using the MPEG-4 ALS conformance test file and normal music files. The complexity of MPEG-4 ALS encoder is reduced by about 24% by comparing with MPEG-4 ALS reference encoder, while the compression ratio by the proposed method is comparable to MPEG-4 ALS reference encoder.

• Journal of the Korea Society of Computer and Information
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• v.12 no.2 s.46
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• pp.9-19
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• 2007

In recent, development of wireless internet technology gradually has increased multimedia application in mobile device. Specially, application of grand capacity multimedia contents has increased in mobile environment gradually. MPEG-7 can search multimedia data using various type. But in restricted grand capacity of multimedia, MPEG-7 is used to be limited in desktop computer system mostly. Therefore, management of grand capacity multimedia data has become very important researching topic in mobile environment, and so embedded DBMS based on MPEG-7 for multimedia data management in client-server environment is needed. The system supports restricted hardware resource for multimedia application in mobile device. In this paper, we propose a method for MPEG-7 data clustering that included MPEG-7 data property. On the base of the clustering result, we also develop the embedded multimedia database management system based on MPEG-7 scheme(EMDS:MPEG-7 Scheme Based Embedded Multimedia Database Management System) in mobile device such as PDA.

• Journal of Broadcast Engineering
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• v.8 no.4
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• pp.365-380
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• 2003

Since MPEG-21 IPMP has been working on International Standardization activity such as one of DRM systems from 1997, the standardization is recently re-started even though the activity was interrupted. According to the MPEG Brisbane meeting, the CfR of MPEG-21 IPMP will be determined on the next Hawaii meeting, therefore they will announce the CfP. However the CfP announced in MPEG Hawaii meeting but the CfR didn't announce because of unfinished requirement document job. Finally. the proposed techniques will be submitted till June 2004. In this paper, we explained the requirement of standardization based on a broadcasting circumstance and implemented the system of MPEG-21 including the architecture and IPMP systems, then we showed all functionality within the other MPEG-21 elements engines. In case of multimedia stream broadcasting system, it is a real-time processing system, the implemented MEPG-21 Architecture can be shown the use of Digital Item In the MPEG-21 terminal and additional MPEG-21 element engines.

• Proceedings of the Korea Multimedia Society Conference
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• 2003.11b
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• pp.998-1001
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• 2003

DMB 단말 시스템에서는 Delivery Layer로 다중화 방식인 MPEG-2 TS 와 MPEG-4 System SL를 이용하도록 제안되었다. 본 논문에서는 DMB 단말 시스템에서 사용되는 MPEG 2 $\square$TS는 H/W로 구현하고 MPEG 4 System S/W로 구현하는데 있어서 효율적인 인터페이스를 제안한다.