• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2013년도 춘계학술대회
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• pp.830-832
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• 2013

휴대폰은 이제 단순한 통화 기능 이외에 PC와 함께 동영상 콘텐츠를 시청할 수 있는 효과적인 멀티미디어 기기로 발전하고 있다. 따라서 동영상 콘텐츠의 실효성은 스마트폰으로 스트리밍(Streaming)할 수 있는지 여부와 목적한 내용을 효과적으로 전달 할 수 있는지 여부에 의해 결정된다. 여기서 목적한 내용을 효과적으로 전달 할 수 있는지 여부란 교재 영상과 발언자의 영상이 함께 제공되어야만 효과적인 내용 전달이 됨을 의미한다. 본 논문은 위 두 가지 요건을 충족하는 동영상 콘텐츠 인코딩(encoding) 시스템으로 멀티소스(Multi-Source)의 오디오-비디오를 입력받아 인터넷 상에 실시간 및 VOD 서비스 할 수 있는 비디오 통합 관리 시스템을 제안하였다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권11호
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• pp.4519-4533
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• 2015

Hypertext Transfer Protocol (HTTP) adaptive streaming has become a new trend in video delivery. An HTTP adaptive streaming client needs to effectively estimate resource availability and demand. However, due to the bitrate of the video encoded in variable bitrate (VBR) mode, a bitrate mismatch problem occurs. With the rising demand for mobile devices, the likelihood of cases where two or more HTTP adaptive streaming clients share the same network bottleneck and competing for available bandwidth will increase. These mismatch and competition issues lead to network congestion, which adversely affects the Quality of Experience (QoE). To solve these problem, we propose a video rate adaptation scheme for the HTTP video streaming to guarantee and optimize the QoE. The proposed scheme estimates the available bandwidth according to the bitrate of each segment and also schedules the segment request time to expedite the response to the bandwidth variation. We used a multi-client simulation to prove that our scheme can effectively cope with drastic changes in the connection throughput and video bitrate.

• 한국정보통신학회논문지
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• 제19권4호
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• pp.825-840
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• 2015

적응 비트 레이트 (ABR) 스트리밍은, 이를 사용하는 넷플릭스나 아마존과 같은 콘텐츠 제공자와 더불어 대역폭 효율을 증가시키고, 채널 상태가 좋지 않은 경우에서도 최고의 사용자 실감을 제공한다는 측면에서, 많은 멀티미디어 전달 시스템 중에서 매우 중요한 기능이 되었다. 이러한 시스템에 의하여 대역폭 이용 효율의 개선이 이루어지는 분야는, 실시간 영상전송을 위한 인지형 폐루프 제어가 가능한 비디오 인코딩 분야이다. 본 연구에서는, 지능적으로 해상도를 결정하기 위하여, 사용자 선호도를 학습함으로써, 공간 및 시간적으로 채널 상태에 적응된 비디오 스트림을 제공하는 스트리밍 카메라 시스템을 제시한다. 제시된 시스템은 비디오 압축을 위하여 하드웨어 H.264 / AVC 인코더를 사용한다. 대역폭이 변동할 때 인코딩 매개변수는 사용자 또는 사용자를 대신할 수 있는 인지형 시스템에 의해 구성될 수 있다. 본 연구에서 개발된 인지형 비디오 클라이언트는, 시간이 지남에 따라 프레임 전송률 대비 비디오 크기와 같은 사용자 선호도를 학습하고, 채널 상태가 변동할 때 지능적으로 인코딩 매개변수를 적응 구성하게 된다. 개발된 인지형 해상도 결정 시스템에서는, 공간 및 시간적 해상도를 적절히 선택하여 비디오 대역폭을 제어할 수 있을 뿐만 아니라, 학습을 통하여 그 해상도를 적응적으로 결정할 수 있다는 것을 실험을 통하여 입증하였다.

• International journal of advanced smart convergence
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• 제8권3호
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• pp.167-176
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• 2019

Building skins are expanding even beyond theirfunctions as a simple boundary between the exterior and interior and into the realm of linguistic functions thanks to the development of media art. LED has been used as material on outer walls following the advancement of building materials, so the outerskins of large buildings are evolving into a messenger of language capable of communication. In big cities, buildings send out video images to enable communication between people and architecture, which plays a huge role in determining the identity of a building beyond simple advertising. Such media fa?ade technologies can be understood based on the concept of outerskin change, which refers to the idea that animals change the colors or textures of their skins to show their various states. In addition, various message delivery functions in human clothes should be included in such a discussion. We need to research on the possibilities of seeing media facades for their information delivery function and expanding them into information delivery between buildings as well as just between buildings and people.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제7권10호
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• pp.2430-2447
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• 2013

In recent years, HTTP adaptive streaming (HAS) has attracted considerable attention as the state-of-the-art technology for video transport. HAS dynamically adjusts the quality of video streaming according to the network bandwidth and device capability of users. Content-Centric Networking (CCN) has also emerged as a future Internet architecture, which is a novel communication paradigm that integrates content delivery as a native network primitive. These trends have led to the new research issue of harmonizing HAS with the in-network caching provided by CCN routers. Previous research has shown that the performance of HAS can be improved by using the H.264/SVC(scalable video codec) in the in-network caching environments. However, the previous study did not address the misbehavior that causes video freeze when overestimating the available network bandwidth, which is attributable to the high cache hit rate. Thus, we propose a new SVC-based adaptation algorithm that utilizes a drop timer. Our approach aims to stop the downloading of additional enhancement layers that are not cached in the local CCN routers in a timely manner, thereby preventing excessive consumption of the video buffer. We implemented our algorithm in the SVC-HAS client and deployed a testbed that could run Smooth-Streaming, which is one of the most popular HAS solutions, over CCNx, which is the reference implementation of CCN. Our experimental results showed that the proposed scheme (SLA) could avoid video freeze in an effective manner, but without reducing the high hit rate on the CCN routers or affecting the high video quality on the SVC-HAS client.

• 한국통신학회논문지
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• 제35권11B호
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• pp.1732-1737
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• 2010

현재 군에서 무인기를 운용하는 주목적 중 하나는 적에 대한 감시/정찰이다. 이를 위해 무인기는 정보감시/정찰(ISR) 장비들을 탑재하여, 감시/정찰 대상에 대한 영상 데이터를 획득한 후 지상통제소로 전송한다. 지상통제소는 전송된 영상 데이터를 수신한 후, 다양한 사용자에게 배포하게 되는 데, 이 때 품질 보장을 유지하는 것이 중요하다. 본 논문에서는 DDS 표준 프로토콜을 사용하여 무인기의 영상전송 및 품질보장을 관리하는 방안을 제시하였다. 이에 대해 H.264 및 JPEG2000 영상 데이터를 이용하여 영상전송 실험결과 DDS 표준이 UAS 운용에 활용 가능함을 보였다.

• International Journal of Internet, Broadcasting and Communication
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• 제7권1호
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• pp.10-14
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• 2015

Video Content owners seek to squeeze the maximum amount of revenue from their assets via distribution into more territories. Digital Cinema Package(DCP), trusted solution to distribute protected content to theaters, caters to relatively small user base, which limits revenue. With the growth of the Internet & other digital media, the economics of media content has changed dramatically. Security remains main concern to deliver content to millions of consumers using intelligent digital display devices like Tablets, Smartphones, Smart TVs, Desktop & Laptop. By making the video content available to this segment securely, content owners will benefit from increased revenue. Through this paper we propose Open Source HomeDCP model to distribute the content to home users for offline viewing. We propose to include other open source CODEC than JPEG2000/MPEG2, which are specifically designed for theatrical performance. Final image size will be further reduced considering the display device resolution where video will be finally played. Key Delivery Message(KDM) system to be altered to suit new devices. This will be a big boost to Content Economy as content owners would be able to distribute the content securely to the wider audience & ensure more revenue.

• International Journal of Contents
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• 제16권4호
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• pp.84-97
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• 2020

Since national image video advertisements are a means of public relations with wide delivery and major repercussions at home and abroad, this study performs a comparative analysis of video advertisements aired by previous governments as reported by Daejung Kim, Moohyun Roh, Myungbak Lee, and Geunhye Park. The characteristics of the previous governments, whether or not social trends were reflected, and the importance of traditional and modern elements were examined. As we describe, there are clear differences in video advertisements by government regime, and while messages expressing traditional values of Eastern culture have gradually decreased, reflecting the trends of the times, the messages emphasizing the modern values of the West have gradually increased. Our research confirmed that traditional elements such as 'Samulnori' and 'Taekwondo' are gradually disappearing. In addition, it was confirmed that the collective values, traditional values, and humanism represented by the 'large crowd' and 'traditional elements' in the Kim Dae-jung and Roh Moo-hyun administration changed in the Lee Myung-bak and Park Geun-hye administrations to more individualistic, materialistic, Western values. This study is meaningful in that it analyzed the components and characteristics of national image advertisements by governments in the past, how social trends were reflected, and the weight difference between traditional and modern elements. Based on this research, the significance of the current Moon Jae-in government's groundwork for follow-up research should not be understated.

• Journal of Information Processing Systems
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• 제18권1호
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• pp.1-11
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• 2022

Online video telephony systems have been increasingly used in several industrial areas because of coronavirus disease 2019 (COVID-19) spread. The existing session initiation protocol (SIP)-based video call system is being usefully utilized, however, there is a limitation that it is very inconvenient for users to transmit additional information during conversation to the other party in real time. To overcome this problem, an enhanced scheme is presented based on augmented real-time reality (AR). In this scheme, augmented information is automatically searched from the Internet and displayed on the user's device during video telephony. The proposed approach was qualitatively evaluated by comparing it with other conferencing systems. Furthermore, to evaluate the feasibility of the approach, we implemented a simple network application that can generate SIP call requests and answer with AR object pre-fetching. Using this application, the call setup time was measured and compared between the original SIP and pre-fetching schemes. The advantage of this approach is that it can increase the convenience of a user's mobile phone by providing a way to automatically deliver the required text or images to the receiving side.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅳ
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• pp.1843-1846
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• 2003

In MPEG-21 Multimedia Framework, Digital Item (DI) is the minimum unit fur processing and delivering the multimedia contents. So how to process, manipulate and represent DI is a very important problem in the standpoint of interoperability for each terminal and provide., and Digital Item Processing (DIP) regarding this issue. This paper suggests technologies which are concerning how DIP should interact with other parts of MPEG-21 (Digital Item Adaptation (DIA), Intellectual Property Management and Protection (IPMP), etc.). For this concept, this paper uses the video summary contents which can describe the hierarchical structures of original multimedia contents. In MPEG-21 environment, the usage of this summary video is very useful delivery and consumption way in view of network burden, efficient accessing to contents.