• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제16권4호
• /
• pp.1249-1265
• /
• 2022

Video streaming has become one of the most popular applications for mobile devices. The network bandwidth required for video streaming continues to exponentially increase as video quality increases and the user base grows. Multi-Path TCP (MPTCP), which allows devices to communicate simultaneously through multiple network interfaces, is one of the solutions for providing robust and reliable streaming of such high-definition video. However, mobile video streaming over MPTCP raises new concerns, e.g., power consumption and cellular data usage, since mobile device resources are constrained, and users prefer to minimize such costs. In this work, we propose a mobile video streaming framework over MPTCP (mDASH) to reduce the costs of energy and cellular data usage while preserving feasible streaming quality. Our evaluation results show that by utilizing knowledge about video behavior, mDASH can reduce energy consumption by up to around 20%, and cellular usage by 15% points, with minimal quality degradation.

• Educational Technology International
• /
• 제23권2호
• /
• pp.129-155
• /
• 2022

This study sought to design and develop an interactive video player (IVP) capable of promoting student engagement through the use of online video content. We designed features built upon interactive, constructive, active, passive (ICAP), and crowd learning frameworks. In the development stage of this study, we integrated numerous interactive features into the IVP intended to help learners shift from passive to interactive learning activities. We then explored the effectiveness and usability of the developed IVP by conducting an experiment in which we evaluated students' exam scores after using either our IVP or a conventional video player. There were 158 college students who participated in the study; 76 students in the treatment group used the IVP and 82 students in the control group used a conventional video player. Results indicate that the participants in the experiment group demonstrated better achievement than the participants in the control group. We further discuss the implications of this study based on an additional survey that was administered to disclose how usable the participants perceived the IVP to be.

• 한국방송∙미디어공학회:학술대회논문집
• /
• 한국방송∙미디어공학회 2022년도 추계학술대회
• /
• pp.171-174
• /
• 2022

Weakly-supervised learning is a widely adopted approach in video anomaly detection whereby only video labels are utilized instead of expensive frame-level annotations. Since the success of multi-instance learning (MIL), almost all recent approaches are based on maximizing the margin between the set of abnormal video snippets and those of normal video snippets. In this work, we present a simple contrastive approach for weakly supervised video anomaly detection (WS-VAD) with aims to enhance the performance of existing models. The method is generic in nature and introduces a loss function to encourage attraction of output features from the same video class and repel those from different video classes. Experimental results demonstrate our method can be applied to existing algorithms to improve detection accuracy in public video anomaly dataset.

• 한국정보처리학회:학술대회논문집
• /
• 한국정보처리학회 2011년도 춘계학술발표대회
• /
• pp.1024-1027
• /
• 2011

본 논문은 HD (High-definition) video, SD (Standard-definition) video, low quality video, handset video, 4 가지 Imaging Device 에 대한 프로파일 분석을 통해 비디오 프레임 상에 나타나는 위 변조를 검사하는 방법을 제안한다. High-definition video, Standard-definition video, low quality video, handset video 에 대한 분석을 하고 각 영상의 특이 점을 파악 하여 분류한 클래스에 대한 프로파일검사를 통해 EM Algorithm 을 이용하여 영상의 위 변조를 검사 하고 영상의 신뢰성을 높인다.

• 한국컴퓨터정보학회논문지
• /
• 제14권6호
• /
• pp.117-123
• /
• 2009

본 논문에서는 일반적인 2차원 비디오 프레임을 패러럴 스테레오 카메라로 촬영한 듯한 3차원 입체 비디오 프레임으로 변환하는 알고리즘을 제안하였다. 동영상의 연속하는 프레임 사이의 픽셀 변위를 구하고 이 변위 정보를 기반으로 입체영상을 합성한다. 픽셀 변위를 구하기 위하여 기존 수렴 반복법을 개선 보완하여 사용하였으며 픽셀변위 정보로부터 입체영상을 합성하는 방법을 제안하였다. 본 연구에서 제안한 알고리즘은 동영상의 어떤 유형이라도 일관성 있는 방법에 의하여 합성영상을 만들어 내므로 기존의 영상 유형 분류에 의한 합성 방법의 문제점을 개선하였다.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
• /
• pp.3306-3311
• /
• 2011

Last Subway video surveillance system consists of a network device that is used. Through the network to transmit video data to digital conversion of analog video via a process server or a PC video to a split-screen in various forms is expressed. In recent years, multi-monitor video cameras from the same pop-up or more, such as history, structure expressed on a variety of video is required by express. The problem with these systems, video compression and transmission of many cameras, and this image data received from the server or PC to take out all the images you want to watch to occur when in order to express all of the images because of the need to decode most of the program per limit of number of channels is positioned. This limited number of channels to have a video that nothing forced, but it is likely to do so in the future performance of the hardware evolves gradually channeled images available number of channels will increase proportionately. However, as the development of hardware required for a single screen video channel will be more gradual capital. The hardware rather than relying solely on the performance of the decoded video data on the screen in order to express a more efficient utilization of shared memory for video surveillance software will provide the operating plan.

• 한국콘텐츠학회논문지
• /
• 제14권4호
• /
• pp.9-18
• /
• 2014

최근에 무선 비디오 감사, 무선 비디오 센서 네트워크 그리고 무선 모바일 비디오와 같은 다시점 비디오 서비스에 대한 연구가 활발히 진행되고 있다. 다시점 비디오 신호처리에서 다수 개의 다른 카메라에서 획득되는 영상 사이에 존재하는 높은 상관성을 이용하는 것은 매우 핵심적인 기술이다. 본 논문에서는 카메라들 사이에 상호작용을 요구하지 않고, 다시점 분산 비디오 부호화에 효과적으로 사용할 수 있는 적응적인 다시점 보간 기법을 제안한다. 제안한 방법은 비선형적인 블록 예측, 시차 보상 시점 예측 그리고 비신뢰 블록에 대한 채우기 기법 등으로 구성된다. 모의실험을 통하여 제안한 방식은 기존의 방식에 비해 우수한 성능을 보인다.

• ETRI Journal
• /
• 제36권2호
• /
• pp.242-252
• /
• 2014

Since July of 2012, the 3D video extension of H.264/AVC has been under development to support the multi-view video plus depth format. In 3D video applications such as multi-view and free-view point applications, synthesized views are generated using coded texture video and coded depth video. Such synthesized views can be distorted by quantization noise and inaccuracy of 3D wrapping positions, thus it is important to improve their quality where possible. To achieve this, the relationship among the depth video, texture video, and synthesized view is investigated herein. Based on this investigation, an edge noise suppression filtering process to preserve the edges of the depth video and a method based on a total variation approach to maximum a posteriori probability estimates for reducing the quantization noise of the coded texture video. The experiment results show that the proposed methods improve the peak signal-to-noise ratio and visual quality of a synthesized view compared to a synthesized view without post processing methods.

• ETRI Journal
• /
• 제36권2호
• /
• pp.253-263
• /
• 2014

In the near future, traditional narrow and fixed viewpoint video services will be replaced by high-quality panorama video services. This paper proposes a visual-attention-aware progressive region of interest (RoI) trick mode streaming service (VA-PRTS) that prioritizes video data to transmit according to the visual attention and transmits prioritized video data progressively. VA-PRTS enables the receiver to speed up the time to display without degrading the perceptual quality. For the proposed VA-PRTS, this paper defines a cutoff visual attention metric algorithm to determine the quality of the encoded video slice based on the capability of visual attention and the progressive streaming method based on the priority of RoI video data. Compared to conventional methods, VA-PRTS increases the bitrate saving by over 57% and decreases the interactive delay by over 66%, while maintaining a level of perceptual video quality. The experiment results show that the proposed VA-PRTS improves the quality of the viewer experience for interactive panoramic video streaming services. The development results show that the VA-PRTS has highly practical real-field feasibility.

• 한국멀티미디어학회논문지
• /
• 제23권6호
• /
• pp.792-801
• /
• 2020

Today, the media environment has changed dramatically with the development of Internet transmission technology, computer performance, and various media production technologies. In particular, video content is widely used every day through mobile device or computer connected to the Internet. In addition, the ability to produce video content today is more important than ever, as the use of video content is also increasing in the area of information delivery and communication over the Internet. In this study, it was developed a liberal education curriculum in universities for the production of video content. The developed curriculum was composed of a combination of an online curriculum for theory and an offline curriculum for practicum. In the online curriculum, a 54 DOOR contents were developed to allow students to learn the theoretical knowledge and basic making techniques related to the production of video content. In an offline 15-week practicum curriculum, it covered the practical training contents of video content production that should be acquired every week. This developed liberal education curriculum aims to give non-major students in universities the opportunity to learn the technology of producing video content and to foster the ability to communicate in the media environment by using the video content produced.