• Proceedings of the Korea Information Processing Society Conference
• /
• 2010.11a
• /
• pp.1027-1028
• /
• 2010

현재 인터넷의 구조적 문제점을 해결 하기 위한 미래 인터넷 연구는 컨텐츠 기반의 네트워크를 대상으로 하고 있다. 컨텐츠 중심의 네트워크(CCN)에서는 중계 노드가 컨텐츠 데이터를 저장 하고 있다. 하지만 사용자의 환경에 적합한 컨텐츠를 보내기 위해서는 트랜스코딩 과정이 필요 하다. 우리는 이 과정의 오버헤드를 줄이기 위하여 비디오 컨텐츠를 단계별로 계층화 시킬 수 있는 H.264/SVC 코덱을 사용하여, CCN 의 중계 노드에서 사용자 환경에 맞추어 다른 계층의 비디오 컨텐츠 전송을 가능 하게 하는 기법을 제시한다.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2011.04a
• /
• pp.1116-1119
• /
• 2011

최근 유무선망의 통합과 통방 융합으로 기존의 방송국 사업자들을 통한 일률적이고 획일적인 서비스 제공 및 소비에서 4A(Any-time, Any-where, Any-device, Any-contents)서비스를 위한 차세대 멀티미디어 방송 서비스에 대한 연구가 진행되고 있다. 이러한 차세대 멀티미디어 방송 서비스에 대한 요구를 보장하기 위해서 비디오 압축 부호화 기술뿐만 아니라 이동성, 다양한 디바이스의 연상능력, 사용자 네트워크의 특성 및 성능과 조건 등의 상태, 사용자 선호도 등에 대한 상황인지 기반의 기술연구에 대한 관심이 모아졌다. 본 논문에서는 현재의 인터넷 환경에서 SVC(Scalable Video Coding)부호화를 이용하여 멀티캐스트와 오버레이 멀티캐스트 전송기술을 혼합한 방송 서비스를 설계함으로써 효율적인 상황인지 기반의 SVC 멀티미디어 방송 시스템을 제안한다.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2011.11a
• /
• pp.573-576
• /
• 2011

Research on 4A(Any-time, Any-where, Any-device, Any-contents) services for the next-generation multimedia services is developed with the trend of the integration of wire and wireless networks and the convergence of telecommunications and broadcasting. In this paper we proposed a design of SVC(Scalable Video Coding) overlay multicast mechanism which can provide typical next-generation multimedia services such as SVC streaming. A novel overlay multicast algorithm called ACK-Flow tree optimization algorithm is proposed to guarantee SVC streaming with high efficiency.

• The KIPS Transactions:PartB
• /
• v.18B no.5
• /
• pp.249-254
• /
• 2011

FGS (fine granularity scalability) supporting scalability in MPEG-4 Part 2 is a scalable video coding scheme that provides bit-rate adaptation to varying network bandwidth thereby achieving of its optimal video quality. In this paper, we proposed FGS coding scheme which performs one more bit-plane coding for residue signal occured in the enhancement-layer of the basic FGS coding scheme. The experiment evaluated in terms of video quality scalability of the proposed FGS coding scheme by comparing with FGS coding scheme of the MPEG-4 verification model (VM-FGS). The comparison was conducted by analysis of PSNR values of three tested video sequences. The results showed that when using rate control algorithm VM5+, the proposed FGS coding scheme obtained Y, U, V PSNR of 0.4 dB, 9.4 dB, 9 dB averagely higher and when using fixed QP value 17, obtained Y, U, V PSNR of 4.61 dB, 20.21 dB, 16.56 dB averagely higher than the existing VM-FGS. From results, we found that the proposed FGS coding scheme has higher video quality scalability to be able to achieve video quality from minimum to maximum than VM-FGS.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2010.10a
• /
• pp.643-645
• /
• 2010

The Internet-based multimedia services such as IPTV is being expanded with the development of technology to support the convergence of broadcasting and telecommunications technology for the control seems to be growing larger. Especially for the real-time TV broadcast multicast control technology to support the authentication and resource control, in addition to the technology services that enhance the value of technology for a variety of services in both directions seems to be developed. And, Internet-based transmission system transmit the video content for the video content delivery using RTP(Real Time Transport Protocol). Standardization body, IETF(Internet Engineering Task Force) within the RTP, according to a variety of audio and video formats only transmission format(RTP Payload Format) Establish a separate standard and scalable video content "RTP Payload Format for SVC(Switched Virtual Connection) Video" the standardization is currently processing. In this paper we are improving the quality of broadcasting and telecommunication systems, so that the upper layer by the application can react adaptively to the existing MPEG2-TS and RTP who are provided by a variety of content applied to a variety of devices consumers ETE(End- to-End) QoS(Quality of Service) for enhance the system who was designed and implemented.

• Journal of Digital Contents Society
• /
• v.17 no.3
• /
• pp.135-142
• /
• 2016

When video service is performed in simulation using NS-2(Network Simulation-2), the video replay is performed as the received frame order. In the existing video replay method based on the received frame order, as the frame orders of receiver and transmitter are different, the receiver buffer does not have the effect that the packets between the frames of transmitter buffer holds a regular size and packet dense and sparsity phenomenon in the receiver buffer is made by the irregular packet size due to the unpredictable reversed order of received partial frames. The above dense and sparsity phenomenon increases the probability of buffer overflow and underflow generation. To prevent these problems, the proposed frame receive order relocation method adds an extra replay buffer which rearranges the order of receive frame as the order of transmit frame, so it has the effect that the packets between the transmit frames keeps a regular size. Through the simulation using NS-2 and JSVM(Joint Scalable Video Model), the generation number of buffer overflow and underflow, and PSNR(Required Peak Signal to Noise Ratio) performance between the existing method and proposed method were compared. As a result, it was found that the proposed method would have better performance than the existing method.

• Proceedings of the Korea Contents Association Conference
• /
• 2009.05a
• /
• pp.726-730
• /
• 2009

The proliferation of the web and digital photography has drastically increased multimedia data and has resulted in the need of the high quality internet service based on the moving picture like user generated contents(UGC). The keyword-based search on large scale images and video collections is too expensive and requires much manual intervention. Therefore the web search engine may provide the content-based retrieval on the multimedia data for search accuracy and customer satisfaction. In this paper, we propose a novel distributed index structure based on multiple length signature files according to data distribution. In addition, we describe how our scalable index technique can be used to find the nearest neighbors in the cluster environments.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.34 no.9B
• /
• pp.923-930
• /
• 2009

Digital Rights Management(DRM) is a term that refers technologies for imposing limitations on the use of digital content for protecting media copyright holders. This paper proposes a generic scheme for digital media copy protection that can be applied to any digital media such as audio, video, etc. The scheme will make it very hard to play a copied content on a foreign platform and to guess secret content encryption keys. Unlike other DRM techniques, the scheme uses the stream cipher HC-256 only for encrypting media content and it allows a client to start content playback immediately following its streamed decryption. As to the encryption, it requires to generate several secret keys for each new client(player copy), rather than for each media content, which makes it scalable in terms of managed keys. Also, for simplicity, the scheme supports the popular unlimited-play-after-download policy only, which would eliminate the necessity for deploying separate server or process for licensing.

• Journal of Broadcast Engineering
• /
• v.27 no.3
• /
• pp.295-307
• /
• 2022

In this paper, we propose a novel compression method for scalable Fisher vectors (SCFV) which is used as a global visual feature description of individual video frames in MPEG CDVA standard. CDVA standard has adopted a temporal descriptor redundancy removal technique that takes advantage of the correlation between global feature descriptors for adjacent keyframes. However, due to the variable length property of SCFV, the temporal redundancy removal scheme often results in inferior compression efficiency. It is even worse than the case when the SCFVs are not compressed at all. To enhance the compression efficiency, we propose an asymmetric SCFV difference computation method and a SCFV reconstruction method. Experiments on the FIVR dataset show that the proposed method significantly improves the compression efficiency compared to the original CDVA Experimental Model implementation.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.35 no.3B
• /
• pp.380-389
• /
• 2010

Since the internet is intend to be the best effort service, the system that stream a large amount of high quality medias need a techniques to overcome the network status for implementation. In this paper, we design and implement a method that estimate quickly whether network permits the needed bandwidth of media and a method that control QoS through that. Presented system uses Relative One-Way Delay(ROWD) trend in the case of the former, and leverages temporal encoding among Scalable Video Coding(SVC) that is apt to apply real time comparatively in the case of the latter. The streaming server classifies the medias by real time to several rates and begins transmission from top-level and is reported ROWD trend periodically from the client. In case of the server reported only 'Increase Trend', the sever decides that the current media exceeds the available bandwidth and downgrades the next media level. The system uses probe packet of difference quantity of the target level and the present level for upgrading the media level. In case of the server reported only 'No Increase Trend' by the ROWD trend response of the probe packet from client, the media level is upgraded. The experiment result in a fiber to the home(FTTH) environment shows progress that proposed system adapts faster in change of available bandwidth and shows that quality of service also improves.