• 전자공학회논문지 IE
• /
• v.43 no.4
• /
• pp.37-42
• /
• 2006

This paper proposes a adaptive video watermarking algorithm according to bitrate and motion vector size in MPEG2 system. The watermark strength in the I-frames is adapted for quantization step size and the strength in the P-B-frames is adapted for quantization step size and motion vector of macroblock to make the watermark more robust against the accompanying degradation due to aggressively compression. A realtime watermark extraction is done directly in the DCT domain during MPEG decoding without full decoding of MPEG video. The experimental simulations show that the video quality results almost invisible difference between the watermarked frames and the original frames and the watermark is resistant to frame dropping, MPEG compression, GoP conversion and low pass filter attacks.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.5 no.5
• /
• pp.465-470
• /
• 2010

This paper proposes an adaptive video watermarking algorithm according to bit detection rate of watermark in MPEG2 system. The watermark strength is adaptively applied as BER(bit error rate) of watermark extracted from decoded frame for motion compensation. Watermark insertion uses a frequency spread spectrum method. A realtime watermark extraction is done directly in the DCT domain during MPEG decoding. The experimental simulations show that PSNR(peak signal to noise ratio) results 31.5dB for a fixed watermark strength and 33.dB for an adaptive watermark strength. Also average BER is 0.126 and less than 0.2 avaliable value.

• 한국HCI학회:학술대회논문집
• /
• 2008.02a
• /
• pp.218-223
• /
• 2008

In this paper, we implement several methods to improve an audio collaboration system over IP networks, and then evaluate the performance of the implemented methods. In general, speech and audio quality degrades depending on the characteristics of IP networks such as jitter and packet loss. In order to reduce this quality degradation, we propose a lower bit rate audio delivery scheme using the MPEG-2 AAC (Advanced Audio Coding) audio codec in a viewpoint that a packet loss rate could be reduced by a smaller packet size. In addition, iLBC (Internet Low-Bitrate Codec) and the G.711 packet loss concealment algorithm defined by IEFT and ITU-T, respectively, are applied to a audio collaboration system. RAT (Robust-Audio Tool)[7] is used as a baseline platform for the implementation of the proposed methods. It is shown from the implementation that the implemented MPEG-2 AAC audio codec with a bitrate of 256 kbit/s performs as similar as the uncompressed audio quality with a bitrate of 512 kbit/s, and that iLBC and the G.711 packet loss concealment algorithm can improve speech quality when a packet loss rate is 2~10%.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2000.10b
• /
• pp.1321-1324
• /
• 2000

본 논문에서는 한국전자통신연구원 VR 연구센터에서 개발한 비선형 MPEG-2 편질 시스템인 "솔거(Solger2001)" 에 사용되는 스트림 형식 변환기를 소개한다. 기존 솔거의 단점으로 여겨져 왔던 다양한 입력 스트림을 지원하지 않는 문제점을 해결하고자 기존의 많은 비선형 편집기에서 입력 포맷으로 사용되고 있는 AVI를 지원하도록 하여 솔거의 활용 범위를 넓혔다.

• Proceedings of the IEEK Conference
• /
• 1999.11a
• /
• pp.1123-1126
• /
• 1999

In this paper, we propose a real-time implementation of the MPEG-1 layer III and MPEG-2 layer III LSF audio decoding system based on OAK DSP Core. In order to solve the problem of resolution, the system has been used floating-point operation and double precision in dequantization module. The size of ROM is reduced by using the Run-length algorithm of reordered index. The subband synthesis filter module is optimized to have low computational complexity in terms of the size of ROM or RAM. To construct a efficient system, we used both the DSP Core and Parser-Huffman decoder which is implemented with VHDL.

• Journal of Broadcast Engineering
• /
• v.9 no.2
• /
• pp.151-163
• /
• 2004

In this paper, we propose a content-based video indexing and retrieval system using MPEG-7 standard to retrieve and manage videos efficiently. The proposed system consists of video indexing module for a video DB and video retrieval module to allow various query methods on a web environment. Video indexing module stores metadata such as manually typed in keywords, automatically recognized character names, and MPEG-7 visual descriptors extracted by indexing module into a DB in a sever side. A user can access to retrieval module by a web and retrieve desired videos through various query methods like keywords, faces, example and sketch. For this retrieval system, we propose ATC(Adaptive Twin Comparison) as a cut detection method for efficient video indexing and QBME(Query By Modified Example) as an improved content-based query method for the convenience of users. Experimental results show that the proposed ATC method detects cuts well and the proposed QBME method provides the conveniences better than existing query methods such as QBE(Query By Example) and QBS(Query By Sketch).

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2004.11a
• /
• pp.43-46
• /
• 2004

MPEG-21 is an on-progress project of the Moving Picture Expert Group (MPEG) that has been started in many independent parts such as part for standardizing the declaration of a digital item (MPEG-21 Part 2: Digital Item Declaration), right expression language (MPEG-21 Part S: Rights Expression Language), way to process the digital item (MPEG-21 Part 10: Digital Item Processing), etc. All this part is intended to form a framework to enable transparent and augmented use of multimedia resources across a wide range of networks and devices (1). In this paper, we show our research initiative to develop a web-based application that utilized many parts of MPEG-21 technology. The implemented concept uses a digital item and license providers in the server side while the MPEG-21 Conformant application is implemented as a plug-in application that will be downloaded to the user terminal when user accesses the webpage for the frist time. The result of this research shows that with some combination of MPEG-21 parts, we can develop an authorized multimedia delivery and consumption application.

• Proceedings of the Korean Information Science Society Conference
• /
• 2006.10a
• /
• pp.203-208
• /
• 2006

본 논문에서는 MPEG-21 프레임워크를 Peer-to-Peer Network 상에서 구동시킬 때의 문제점을 해결하면서, P2P의 장점을 최대한 이용할 수 있도록 하는 P2P 방식의 디지털 권한 관리 시스템(P2PDRMEngine)을 설계한다. MPEG-21 프레임워크의 여러 구성 요소들 중 IPMP(Intellectual Property Management and Protection components), DI(Digital Item), Multimedia Contents 등의 구조에 몇 가지 요소를 추가하여 P2PDRMEngine과 MPEG-21 프레임워크가 서로 유기적인 동작을 할 수 있도록 설계하고 또한, DI를 생산, 배포, 사용할 때 사용자에게 편리성을 제공 해주는 기능도 고려한다. P2PDRMEngine은 기존의 MPEG-21 프레임워크의 수행에 지장을 주지 않으면서 보안적인 측면과 요소 간의 기능을 강화하는 데 초점을 맞추어 설계한 시스템이다.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2003.11a
• /
• pp.583-586
• /
• 2003

다양해진 디지털 미디어와 디지틀 컨텐츠의 유통이 점차 대용량화에 따른 변화와 콘텐츠 서비스 환경 구축의 개발이 본격화되고있다. 또한 다룰 수 있는 사용자 단말기의 다양화로 인해, 자원을 식별하고 검색하기 위한 식별기호의 중요성이 인식되어져 왔다. 이러한 물리적 콘텐츠와 디지털 콘텐츠의 통합 서비스의 방안으로 정보자원에 대한 효율적인 접근과 저작권 보호를 위한 필요성에 의해 2차원 바코드 기술을 이용한 MPEG21 DII의 디지털컨텐츠 식별체제의 운영 방안을 검토한다.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.56 no.5
• /
• pp.987-989
• /
• 2007

This paper describes a digital convergence platform(DCP) which is implemented based on the MPEG-21 multimedia framework. DCP is a newly proposed solution in this research for the convergence service of future home multimedia environment. DCP is a common platform designed to have the feature of reconfigurability, by means of S/W. which supports to run diverse digital multimedia services. A distributed peer to peer service and transaction model is also a new feature realized in DCP using the MPEG-21 multimedia framework. A prototype DCP is implemented to verify its functions of multimedia service and transactions. The developed DCPs are networked with IP clustering storage systems for the distributed service of multimedia. Successful streaming services of the MPEG-2/4 video and audio are verified with the implemented test-bed system of DCP.