Earticle

Online video services are responsible for a large amount of global data traffic, which is why wireless video caching has become a major focus in order to deal with the increasing amount of data. While conventional caching methods have been successful in reducing file transmission latency and data traffic on the core network, there is still a lot of potential to improve wireless caching for streaming users’ satisfaction, especially as video streaming technology continues to improve. To improve caching, it is important to consider the distinct characteristics of a video file, video encoding, dynamic video streaming, and even 3D video services such as virtual reality (VR) and augmented reality (AR). This paper investigates the distinct video features that can be used to design video caching policies. Additionally, recent studies on wireless video caching and delivery are surveyed, with a focus on four key characteristics: (1) partitioning a video file, (2) encoding a video file into multiple quality versions, (3) recognizing that video file popularity is dynamic and heterogeneous, and (4) understanding that video recommendation affects a series of user requests.

The vision of space exploration includes missions to deep space that produce significant amounts of video data and require reliable video streaming back to the Earth. The Internet of Deep Space Things (IoDST) is envisioned to provide communication services for video data streaming for the mission spacecrafts. Ensuring reliable communications in IoDST requires Transmission Control Protocol (TCP) layer functionalities. However, current TCP Congestion Control (CC) protocols provide poor performance in IoDST communications primarily owing to the dependence on pre-defined rules to determine the transmission rate in a single path TCP flow. This paper proposes a Multi-Path TCP (MPTCP) CC design for data streaming transmission in IoDST. We utilized Scalable Video Coding (SVC)-based streaming to overcome the Head-of-Line (HoL) blocking and proposed an intelligent CC scheme based on Q-learning and Deep Q-Network (DQN) to solve the problems of challenging link conditions in IoDST. Our proposed CC scheme determines the optimal congestion window for data transmission in IoDST communications to maximize the TCP throughput performance and streaming data playback. Simulation results show that our proposed CC scheme achieves TCP throughput performance by up to approximately 257.14% and 73.08% compared to TCP CUBIC and TCP Westwood. In addition, video streaming playback by up to approximately 164.86%, 104.17%, 75%, 157.89% and 66% compared to TCP CUBIC, TCP BBR, TCP Westwood, DRL-TCP and QLE-DS, respectively. Finally the total streaming data transfer time by up to approximately 61%, 20%, 63%, 21% and 19% compared to TCP CUBIC, TCP BBR, TCP Westwood, DRL-TCP and QLE-DS, respectively.

In the rapidly evolving metaverse ecosystem, video streaming plays a vital role, offering immersive, on-demand experiences and engaging users in dynamic 3D virtual environments. Point cloud video streaming enables detailed 3D representations for applications like 3D scanning, AR, and VR. However, high data demands and complex encoding pose challenges, requiring efficient resource and latency management. As a result, user experience (UX) is critical in the metaverse, where metrics like real-time feedback, Quality of Experience (QoE), and adaptive UX design are essential for sustaining engagement in immersive 3D environments. Therefore, this paper closely examines the latest developments in point cloud video streaming, specifically focusing on user-centric, AI-driven, and low-latency techniques, transcending traditional video streaming methods. We investigate a variety of techniques, pinpoint obstacles, and chart prospective routes for elevating both the quality and depth of immersive experiences. Furthermore, our work includes a detailed qualitative comparison of these streaming paradigms. We also shed light on pivotal metaverse enhancers, such as Mobile Edge Computing (MEC), Visible Light Communication (VLC), advanced network coding techniques, and the integration of the Data Plane Development Kit (DPDK). These enablers?particularly when combined with DPDK’s capabilities in efficient data packet processing?have the potential to optimize resource allocation, strengthen reliability, reduce latency, and improve the sustainability of point cloud video streaming. Our study, therefore, offers a holistic overview of the advancing area of point cloud video streaming and outlines paths for future research and development.

최근의 모바일 장치에서의 진보는 사용자들로 하여금 영상 스트리밍 서비스를 보다 중요한 것으로 만들고 있다. 하지만 지형적 특성에 의한 음영지역의 존재는 이를 어렵게 하고 있다. 이러한 문제점을 극복하기 위해서 음영지역을 위해 콘텐츠를 버퍼링하는 수단이 필요하다. 본 논문에서는 음영지역에서도 끊임없는 영상 스트리밍 서비스를 제공하기 위해 화질 절충 기법을 포함한 방송 시스템을 제안한다. 이 시스템에서는 GPS 신호와 전자지도를 이용한 길안내 시스템을 사용하여 모바일 장치가 음영지역을 예측하여 콘텐츠를 미리 내려받으며 화질의 절충을 통해 음영지역까지 남은 시간 내에 필요한 재생 시간을 확보한다. 결과적으로 사용자는 끊이지 않는 영상을 시청할 수 있다. 시뮬레이션 결과는 이러한 화질 절충 방법이 충분히 적용 가능함을 보여준다.

Recent advance in mobile devices makes seamless video streaming service important for mobile users. However, a user is hard to get contents in the shaded area because of the geographical reasons. To realize the seamless streaming service, a user need to buffer video contents to play before the user enters the shaded area. In this paper, we propose a simple broadcasting system including a quality negotiation scheme of streaming video to provide seamless service even in the shaded area. With the aid of the GPS signal and the digital map, the mobile device predicts a user’s entrance to the shaded area and requests download of contents before the user enters the area. In addition, a negotiation scheme of the video quality and the contents play time makes the mobile device download enough contents to play within the shaded area even the remaining time to download is short. Consequently, the mobile users can seamlessly watch whole stories wherever they are. Simulation results show that our negotiation scheme is adaptable because of the contents’ acceptable quality.

Live video streaming becomes one of the most popular internet activities in the recent years. Along with its popularity, the problems such as scalability, availability and low-latency are still the main drawbacks of the peer-to-peer (P2P) live video streaming. The DHT-aided chunk-driven overlay (DCO) [3] tried to overcome these problems by using the Distributed Hash Table (DHT) in live video streaming. Even the performance of DCO is better than other traditional works such as tree-based system, in terms of vulnerability to churn, and mesh-based system, in terms of high delay and message overhead, there are some problems in DCO which need to be solved. The coordinator is easy to get overloaded by many requests because one coordinator is responsible for storing the chunk index of several segments. Moreover, the number of nodes that the video server is responsible for sending the video segment to are not clearly defined. To solve these problems, in this paper, a more efficient approach of using the coordinator nodes is proposed. Furthermore, the threshold is carefully calculated in order to use the server capacity efficiently. The server is only responsible for sending the video segment to the threshold nodes. After that, the video segment will be shared among nodes in the network until every node receives the video segment. The performance evaluation results show that our work is more efficient than DCO, and the server capacity can be used efficiently if the threshold is careful defined.

뉴 미디어의 발전으로 인해 사람들의 정보 습득 방식에 커다란 변화가 생기고 있다. 글이나 사진보다 콘텐츠 내용을 더 입체적인 전달할 수 있는 영상콘텐츠 활용이 그 변화다. 2016년 이후 실시간 라이브 방송 콘텐츠는 제공자 와 사용자 모두 증가하는 추세이다. 본 논문은 Youtube Live 또는 DouyuTV를 플렛폼으로 하는 개인의 실시간 라이 브 방송 콘텐츠를 연구 대상으로 하였다. 개인의 실시간 라이브 방송 사례에 수록된 디지털화된 정보 내용의 특징 또는 필요성을 분석하였다. 2020년에 코로나19로 인한 온라인 생활의 변화는 실시간 라이브 방송을 더 다양한 분야로 확대 될 수 있음을 보여주었다. 디지털 첨단기술을 용합한 실시간 라이브 방송은 내용적인 측면 뿐만 아니라 영상콘텐츠를 소비하는 대중들의 영상 소비 문화에도 다양성을 제공하여 더 많은 사회적 가치를 만들 것으로 예측된다. 그러므로 향후 실시간 라이브 방송콘텐츠의 사회적 책임에 관한 심도 있는 연구가 필요하다고 생각한다.

With the development of new media, great changes are taking place in the way people get information. The change is the use of video content that can deliver content in a more three-dimensional way than words or photos. After 2016, the number of live video streaming content providers and users has increased. In this paper the write takes the 1 personal live video streaming content as the research object. And the write takes live video streaming content on YouTube live or Douyu TV as a research example. In this paper, the writer analyzes the digital information content in the live video streaming case. And the writer expounds the necessity of these visual information and the characteristics of real-time live video streaming content. Especially since 2020, because of the influence of the COVID-19, the live video streaming industry has begun to combine with the traditional industry. It is expected that the integration of digital cutting-edge technology and live video streaming will not only provide diversity in the content, but also create more social value for the video content consumption culture. Therefore, The writer thinks it is necessary to conduct in-depth research on the social responsibility of real-time live content in the future.

A new trend has been emerging in recent years, with video game live streaming becoming a meeting ground for gamers, as well as a marketing strategy for game developers. In line with this trend, the emergence of the “Let’s Play” culture has significantly changed the manner in which people enjoyed video games. In order to academically explore this new experience, this study seeks to answer the following research questions: (1) Does engaging in video game streaming offer the same feeling as playing the game? (2) If so, what are the factors that affect the feeling of telepresence from viewers’ perspective? and (3) How does the feeling of telepresence affect viewers’ learning experience of the streamed game? We generated and empirically tested a comprehensive research model based on the telepresence and consumer learning theories. The research findings revealed that the authenticity and pleasantness of the streamer and the interaction of viewers positively affect telepresence, which in turn is positively associated with the gained knowledge and a positive attitude toward the streamed game. Based on the research findings, various practical implications are discussed for game developers as well as platform providers.

In this paper, we propose a method for replaying game streaming video using informations of input-key and object states. Up to the present, the played game contents have been just recorded and replayed for game streaming video recording function provided by the game company, this required a large volume of storage device. By the proposed method, it is more efficient for sharing the game informations between the users and game companies, and between the users and other users because it need much less storage device than the present method. And also the game user can handle the additional game informations.

기존의 클라이언트/서버 구조 기반 클라우드 시스템에서의 높은 설치 및 유지비용 문제를 해결하기 위해 P2P 클라 우드 스토리지가 등장하게 되었다. 하지만 현재까지 P2P 클라우드 스토리지에 대한 연구는 주로 데이터 가용성을 보장하는 기술에 초점을 맞추었고 실시간 제약 조건이 있는 비디오의 안정적인 재생에 대한 연구는 거의 진행되지 않았다. 따라서 본 논문에서는 P2P 클라우드 스토리지에서 데이터 가용성뿐만 아니라 효율적인 비디오 전송을 지 원할 수 있도록 복제 기법과 erasure coding 기법의 장점을 동시에 활용하는 하이브리드 데이터 중복 기법을 제안 한다.

To solve the problems caused by such high installation and maintenance cost in the conventional cloud 1)systems based on client/server architectures, P2P cloud storages have been emerged. However, recent research on P2P cloud storages has focused on the technology to guarantee data availability but there have been little research on supporting stable playback of video data with real-time constraints. In this paper, we therefore propose a hybrid data redundancy scheme that takes advantages of both replication and erasure coding simultaneously to support efficient video transmission as well as data availability in P2P cloud storages.

This study empirically examines how the linguistic and non-linguistic behaviors of live-streaming hosts shape interactions with viewers and their effects. The analysis identified the following key interactions: (A) Hosts’ framing statements enhance viewers’ anticipation and engagement, fostering a shared live-streaming experience. (B) Detailed information from hosts captures interest, encourages participation, and facilitates opinion-sharing. (C) Emotional expressions and evaluations elicit empathy, promote personal storytelling, and strengthen emotional bonds. (D) Prompts for specific actions deepen solidarity between hosts and viewers while reinforcing viewer-to-viewer connections. (E) Visual and auditory effects evoke reactions, enhancing presence and a sense of unity. (F) Hosts’ feedback on viewer comments increases engagement and reduces psychological distance. These findings confirm that interactions in live-streaming platforms occur in diverse forms and have various effects on both the host and viewers.

동적 적응 스트리밍 (Dynamic Adaptive Streaming over HTTP (DASH)) 서버는 트랜스코딩된 다양한 비트 율의 비디오 세그먼트를 저장해야 하기 때문에, 스토리지 요구량을 줄이는 것이 매우 중요하다. 본 논문에서는 비디 오 스트리밍 서버에서의 유전 알고리즘을 활용한 사용자 인기도 기반 데이터 배치 기법을 제안한다. 우리는 트랜스 코딩된 다양한 버전의 비디오 세그먼트들 중에서 어떤 버전을 저장하고, 어떻게 세그먼트를 디스크들에 분산시킬 지 에 대한 문제를 정의하고, 유전 알고리즘을 이용한 시뮬레이션 모델을 개발하였다. 이를 위해서 유전 알고리즘의 개 체군의 크기, 선택 비율, 교배 비율, 돌연변이 비율을 설정하기 위한 실험을 진행하였으며, 유전 알고리즘의 결과와 최적값을 비교하여 본 기법의 신뢰성을 확인했다.

It is important to reduce the growing storage requirements of dynamic adaptive streaming over HTTP(DASH) servers that need to store transcoded video segments of various bit rates. In this paper, we propose a new genetic algorithm techniques for popularity-aware data placement in video streaming servers. We defined the popularity-aware data placement problem that chooses and places video segments on each disk. We designed and implemented a simulation model to solve this problem using a genetic algorithm. Experiments were carried out to set the population size, selection rate, crossover rate and mutation rate. We compared the results of the genetic algorithm with the optimum value to confirm the reliability of this technique.

최근 5G의 등장에 따라 국내 스트리밍 시장에서는 360 VR(Virtual Reality) 서비스가 주목받고 있다. 하지만 기존 IPTV(Internet Protocol Television)의 360 VR 영상 서비스에서 사용자가 고품질로 느끼기 위해서는 8K 이상 의 영상이 요구 되지만 현재는 4K 정도의 영상이 서비스되어 사용자의 만족도가 높지 않다. 8K 이상의 영상의 경우 비트율(bitrate)이 하나의 QAM 채널로 전송할 수 있는 38.8107mbps 이상이다. 때문에, 현재 IPTV 방송 케이블망 환경에서 8K 이상의 영상을 스트리밍 하는 것은 불가능 하다. 이에 본 논문에서는 8K이상의 360 VR 서비스를 위해 다수의 QAM 채널을 사용하여 영상을 분리 분산하여 전송하는 방식을 제안하고 설계 하였다. 그리고 IPTV 방송 수신기 에서 댁내의 디스플레이 장치로 저지연 스트리밍을 할 수 있는 엣지 스트리밍 방식을 제안하고 구현하였다. 그리고 실험 을 통해 100mbps 미만의 네트워크 대역폭을 사용하여 500ms 미만의 뷰포트(Viewport) 전환 지연 시간을 갖는 360 VR스트리밍을 할 수 있음을 확인하였다.

360 Virtual Reality(VR) service is getting attention in the domestic streaming market as 5G era is upcoming. However, existing IPTV-based 360 VR video services use upto 4K 360 VR video which is not enough to satisfy customers. It is generally required that over 8K resolution is necessary to meet users' satisfaction level. The bit rate of 8K resolution video exceeds the bandwidth of single QAM channel(38.817mbps), which means that it is impossible to provide 8K resolution video via the IPTV broadcast network environment. Therefore, we suggest and implement the edge streaming system for low-latency streaming to the display devices in the local network. We conducted experiments and confirmed that 360 VR streaming with a viewport switching delay less than 500ms can be achieved while using less than 100mbps of the network bandwidth.

본 연구에서는 스트리밍 기술에 대한 연구를 통해 각 플랫폼에서의 게임 영상의 특징과 기능을 정리했다. 게임 영상은 게임을 소재로 하여 마케팅과 게임플레이 방법 전파 등의 목적으로 게임콘텐츠 자체와 관계성이 높다. 영상 길이가 짧고 전파도 간편하다. 게임 영상 내용의 주된 유형은 게임 해설, 게임전략, 웃기기, 모방하기, 뮤직비디 오, 게임 정보. 게임홍보동영상 기능 등으로 게임에 대한 직․간접적 홍보로서 제작자와 이용자에게 각각의 이유로 활용되어진다. 이 글은 게임 영상의 제작 주체와 제작 조건 등을 제작과정 중심으로 분석하였다. 제작 주체는 직업 창작자, 비 직업 창작자와 일반 사용자로 나뉘며, 게임 동영상 제작 동기는 주로 경제적 실리를 얻기 위해, 게임 영상 제작 방식은 게임 중 무작위로 생성되는 것과 사전 기획 후 촬영하는 것 두 가지다. 게임 동영상에 대한 실례를 통해 제작 과정을 추출 제시하였다.

This paper summarizes the features and functions of game video on each platform through a study on streaming technology. Game videos have a high relationship with game content itself for the purpose of marketing and disseminating game play methods using games as the subject matter. The video length is short and it is easy to spread. The main types of game video content are game commentary, game strategy, funny, imitative, music video, and game information. As a game promotion video function, etc., it is used as a direct or indirect publicity for the game by the producer and the user for each reason. This article analyzed the production subject and production conditions of game videos, focusing on the production process. The production subject is divided into professional creators, non-professional creators, and general users. The motive for producing game videos is mainly to obtain economic benefits. The production process was extracted and presented through examples of game videos.

비디오 트랜스코딩 서버는 응답시간 지연 및 네트워크 부하 문제를 효과적으로 해결하기 위해서 가변 비트레이트 스트리밍 기술을 활용한다. 하지만, 무분별한 비트레이트 변환은 사용자가 느끼는 비디오 화질수준을 저하시킬 여지가있으므로 사용자의 주관적 화질평가 결과를 추정할 수 있는 객관적 화질측정기법을 활용하기 위한 시도가 계속되고있다. 그 중, Structural SIMilarity (SSIM) index 는 이미 잘 알려진 객관적 화질평가도구이다. 그러나 SSIM 은 많은 연산부하를 요구하기 때문에 실시간 환경에서 보다 적합한 객관적 화질측정 도구가 필요하다. 본 논문에서는 객관적 화질평가도구를 활용하는 가변 비트레이트 스트리밍 모델에서 명암도 변화량 측정 기법이 SSIM을 대체할 수 있는 효율적인 도구임을 실험을 통해 제안한다. 명암도 변화량 측정기법의 측정값은 SSIM index와 높은 상관관계를 나타내며 장르, 해상도, 비트레이트에 관계없이 SSIM index를 추정할 수 있다. 이 영상처리기법은 연산부하 측면에서 SSIM 보다 효율적이며 수행시간 실험에서 약 21.2배의 성능차이를 보였다.

Video transcoding server solves the problem such as delay of response time and network overlord of Server by variable bitrate(VBR) streaming techniques. However, indiscreet bitrate conversion must be degrading video quality for end-users. Because of its, an attempt has been continued for estimating subjective quality evaluation score using objective quality assessment. Among them, Structural SIMilarity(SSIM) is already well-known objective quality assessment method. But, because of much requirement about computation resource by SSIM, more suitable objective quality assessment tool than SSIM is necessary for real time environment. In this paper, we will propose through our experiment that pixel intensity variation is more efficient than SSIM in VBR streaming system using video quality assessment tool. Intensity variation has highly correlation to the SSIM-index and estimates scores in regardless of resolution, bitrate and the kinds of video contents. This image processing method is more efficient than SSIM-index in terms of computation lord and show 21.2 times faster than SSIM-index in performance test.

최근 영상 장비와 기술이 발전함에 따라 우리 군에서도 작전지역에 대한 정보를 획득하고, 효율적인 지휘통제에 활용하기 위해 수많은 영상정보가 생산되어 활용되고 있다. 이때 현재 군내에서 활용하고 있는 영상 재생장비는 저성능의 전술용 다기 능 단말기(TMFT)로부터 고성능의 영상서버에 이르기까지 매우 다양하고, 영상이 전송되는 네트워크 또한 저속의 전술정보통 신체계(TICN)로부터 초고속의 국방광대역통합망(M-BcN)에 이르기까지 다양하다. 따라서 이기종(異機種) 통신장비 및 네트 워크 환경에서 국방 영상정보를 효율적으로 전송할 수 있는 스트리밍 기법이 필요하다. 이 문제를 해결하기 위해 본 논문에서 는 확장비디오코딩(SVC) 및 균형선택 알고리즘 기반의 피투피(P2P) 스트리밍 기법을 제안한다. 비토렌트 기반의 시뮬레이터 를 활용한 성능분석결과 우리가 제안하는 균형선택 알고리즘 기반의 스트리밍 기법은 순차선택이나 희소선택 알고리즘에 비해 우수한 성능을 보였다.

Recently, with the rapid development of video equipment and technology, tremendous video information is produced and utilized in military domain to acquire battlefield information or for effective command control. Note that the video playback devices currently used in the military domain ranges from low-performance tactical multi-functional terminals (TMFT) to high-performance video servers and the networks where the video information is transmitted also range from the low speed tactical information and communication network (TICN) to ultra-high speed defense broadband converged networks such as M-BcN. Therefore, there is a need for an efficient streaming technique that can efficiently transmit defense video information in heterogeneous communication equipment and network environments. To solve the problem, this paper proposes a Scalable Video Coding (SVC) and balanced selection algorithm based Peer-to-Peer (P2P) streaming technique and the feasibility of the proposed technique is verified by simulations. The simulation results based on our BitTorrent simulator show that the proposed balanced selection scheme outperforms the sequential or rarest selection algorithm.