• Title/Summary/Keyword: Video Rate

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Spatial Correlation Based Fast Coding Depth Decision and Reference Frame Selection in HEVC (HEVC의 공간적 상관성 기반 고속 부호화 깊이 및 참조영상 결정 방법)

  • Lee, Sang-Yong;Kim, Dong-Hyun;Kim, Jae-Gon;Choi, Hae-Chul;Kim, Jin-Soo;Choi, Jin-Soo
    • Journal of Broadcast Engineering
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    • v.17 no.5
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    • pp.716-724
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    • 2012
  • In this paper, we propose a fast decision method of maximum coding depth decision and reference frame selection in HEVC. To reduce computational complexity and encoding time of HEVC, two methods are proposed. In the first method, the maximum depth of each coding unit (CU) in a largest CU (LCU) is constrained by using the maximum coding depth used by adjacent LCUs based on the assumption that the spatial correlation is very high and rate-distortion (R-D) cost. And we constrain the number of reference pictures for prediction unit (PU) performing motion estimation by using the motion information of the upper depth PU. The proposed methods reduce computational complexity of the HEVC encoder by constraining the maximum coding depth and the reference frame. We could achieve about 39% computational complexity reduction with marginal bitrate increase of 1.2% in the comparison with HM6.1 HEVC reference software.

A Study on the Development of Electronic Resource Management System in a University Library (대학도서관 전자자원관리시스템(ERMS) 구축에 관한 연구)

  • Kim, Yong;Cho, Su-Kyeong
    • Journal of the Korean Society for Library and Information Science
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    • v.44 no.4
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    • pp.249-276
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    • 2010
  • With the rapid growth and development of information technology and the Internet, the amount of information published in electronic formats such as video, audio, digitalized text, etc. and the number of users accessing information online to satisfy their information needs are growing at a tremendous rate. This study analyzes standardized components to construct ERMS and proposes a model of ERMS based on the result of the analysis. The main functions of ERMS in university libraries are: 1) ERMS can manage and control access information to various electronic resources, metadata, holdings, user resources. Also, ERMS can be compatible with an existing library system such as IR(Information Retrieval) system, linking system, or proxy system. 2) ERMS should completely be compatible with acquisition and cataloging systems for effective management and control of integrated information organization and library budget. 3) ERMS should systematically and effectively manage license information on electronic resources. 4) ERMS should provide ideal and effective environment for use and access control of electronic resources in a library and integrated tool to manage and control all of electronic resources. Additionally, this study points out the need to organize committee groups to establish standardized rules and collaborative management of electronic resources among university libraries like DLF ERMI and redesign organizations in a library and a librarian's job description.

Security of Ethernet in Automotive Electric/Electronic Architectures (차량 전자/전기 아키텍쳐에 이더넷 적용을 위한 보안 기술에 대한 연구)

  • Lee, Ho-Yong;Lee, Dong-Hoon
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.16 no.5
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    • pp.39-48
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    • 2016
  • One of the major trends of automotive networking architecture is the introduction of automotive Ethernet. Ethernet is already used in single automotive applications (e.g. to connect high-data-rate sources as video cameras), it is expected that the ongoing standardization at IEEE (IEEE802.3bw - 100BASE-T1, respectively IEEE P802.3bp - 1000BASE-T1) will lead to a much broader adoption in future. Those applications will not be limited to simple point-to-point connections, but may affect Electric/Electronic(EE) Architectures as a whole. It is agreed that IP based traffic via Ethernet could be secured by application of well-established IP security protocols (e.g., IPSec, TLS) combined with additional components like, e.g., automotive firewall or IDS. In the case of safety and real-time related applications on resource constraint devices, the IP based communication is not the favorite option to be used with complicated and performance demanding TLS or IPSec. Those applications will be foreseeable incorporate Layer-2 based communication protocols as, e.g., currently standardized at IEEE[13]. The present paper reflects the state-of-the-art communication concepts with respect to security and identifies architectural challenges and potential solutions for future Ethernet Switch-based EE-Architectures. It also gives an overview and provide insights into the ongoing security relevant standardization activities concerning automotive Ethernet. Furthermore, the properties of non-automotive Ethernet security mechanisms as, e.g., IEEE 802.1AE aka. MACsec or 802.1X Port-based Network Access Control, will be evaluated and the applicability for automotive applications will be assessed.

A Hybrid Approach of Efficient Facial Feature Detection and Tracking for Real-time Face Direction Estimation (실시간 얼굴 방향성 추정을 위한 효율적인 얼굴 특성 검출과 추적의 결합방법)

  • Kim, Woonggi;Chun, Junchul
    • Journal of Internet Computing and Services
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    • v.14 no.6
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    • pp.117-124
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    • 2013
  • In this paper, we present a new method which efficiently estimates a face direction from a sequences of input video images in real time fashion. For this work, the proposed method performs detecting the facial region and major facial features such as both eyes, nose and mouth by using the Haar-like feature, which is relatively not sensitive against light variation, from the detected facial area. Then, it becomes able to track the feature points from every frame using optical flow in real time fashion, and determine the direction of the face based on the feature points tracked. Further, in order to prevent the erroneously recognizing the false positions of the facial features when if the coordinates of the features are lost during the tracking by using optical flow, the proposed method determines the validity of locations of the facial features using the template matching of detected facial features in real time. Depending on the correlation rate of re-considering the detection of the features by the template matching, the face direction estimation process is divided into detecting the facial features again or tracking features while determining the direction of the face. The template matching initially saves the location information of 4 facial features such as the left and right eye, the end of nose and mouse in facial feature detection phase and reevaluated these information when the similarity measure between the stored information and the traced facial information by optical flow is exceed a certain level of threshold by detecting the new facial features from the input image. The proposed approach automatically combines the phase of detecting facial features and the phase of tracking features reciprocally and enables to estimate face pose stably in a real-time fashion. From the experiment, we can prove that the proposed method efficiently estimates face direction.

Lane Change Behavior of Manual Vehicles in Automated Vehicle Platooning Environments (군집주행 환경에서 비자율차의 차로변경행태 분석)

  • LEE, Seol Young;OH, Cheol
    • Journal of Korean Society of Transportation
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    • v.35 no.4
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    • pp.332-347
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    • 2017
  • Analysis of the interaction between the automated vehicles and manual vehicles is very important in analyzing the performance of automated cooperative driving environments. In particular, the automated vehicle platooning can affect the driving behavior of adjacent manual vehicles. The purpose of this study is to analyze the lane change behavior of the manual vehicles in automated vehicle platonning environment and to conduct the experiment and questionnaire surveys in three stages. In the first stage, a video questionnaire survey was conducted, and responsive behaviors of manual vehicles were investigated. In second stage, the driving simulator experiments were conducted to investigate the lane change behaviors of in automated vehicle platonning environments. To analyze the lane change behavior of the manual vehicles, lane change durations and acceleration noise, which are indicators of traffic flow stability, were used. The driving behavior of manual vehicles were compared across different market penetration rates (MPR) of automated vehicles and human factors. Lastly, NASA-TLX (NASA Task Load Index) was used to evaluate the workload of the manual vehicle drivers. As a result of the analysis, it was identified that manual vehicle drivers had psychological burdens while driving in automated vehicle platonning environments. Lane change durations were longer when the MPR of the automated vehicles increased, and acceleration noise were increased in the case of 30-40 years old or female drivers. The results from this study can be used as a fundamental for more realistic traffic simulations reflecting the interaction between the automated vehicles and manual vehicles. It is also expected to effectively support the establishment of valuable transportation management strategy in automated vehicle environments.

A Study on Behaviour of Giant Pacific Octopus, Parotopus dofleini to Single Line Hook for Hook Design (외줄낚시에 대한 대문어의 행동과 낚시형상 설계)

  • Park, Seong-Wook;Lee, Jeong-Woo;Yang, Yong-Su;Seo, Du-Ok
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.40 no.1
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    • pp.1-8
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    • 2004
  • The single line hook fishery for giant pacific octopus, Parotopus dofleini is one of the important in coastal Kangwon-do of Korea, where was caught an average of 4,000 ton during the period of 1996~2000. The fishing gear is consisted of a single buoy line, a buoy and a hook. In this study, the responses of giant pacific octopus to single line hook gear were examined in an experimental tank using a video camera in order to know hooking mechanism and improve hook. Giant pacific octopus tend to envelop the bait with their arms by rush or slowly swimming towards it. When they rush to the bait, they show much feeding behaviour as withdrawing after enveloping the bait using two arms. But when they approach with slowly swimming to bait, they show feeding behaviour as stopping after enveloping the bait using one arm. and then, the highly hooking rate appeared more often in the case of latter then former. The average feeding time on a sardine, giant pacific octopus and pork fat showed the range of 1 to 30 min, 10 to 50 min, and 50 min to over 1 hour, respectively. This indicates that it takes longer time for giant pacific octopus to eat the tough meat than the soft meat. The performance concerned with hooking showed that the 'B' type hook with a short shank was more favorable than the 'A' type hook with a long shank. However, the 'A' type hook has the advantage of easy dropping out caught octopus, compared to the 'B' type.

A LDPC Decoder for DVB-S2 Standard Supporting Multiple Code Rates (DVB-S2 기반에서 다양한 부호화 율을 지원하는 LCPC 복호기)

  • Ryu, Hye-Jin;Lee, Jong-Yeol
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.45 no.2
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    • pp.118-124
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    • 2008
  • For forward error correction, DVB-S2, which is the digital video broadcasting forward error coding and modulation standard for satellite television, uses a system based the concatenation of BCH with LDPC inner coding. In DVB-S2 the LDPC codes are defined for 11 different code rates, which means that a DVB-S2 LDPC decoder should support multiple code rates. Seven of the 11 code rates, 3/5, 2/3, 3/4, 4/5, 5/6, 8/9, and 9/10, are regular and the rest four code rates, 1/4, 1/3, 2/5, and 1/2, are irregular. In this paper we propose a flexible decoder for the regular LDPC codes. We combined the partially parallel decoding architecture that has the advantages in the chip size, the memory efficiency, and the processing rate with Benes network to implement a DVB-S2 LDPC decoder that can support multiple code rates with a block size of 64,800 and can configure the interconnection between the variable nodes and the check nodes according to the parity-check matrix. The proposed decoder runs correctly at the frequency of 200MHz enabling 193.2Mbps decoding throughput. The area of the proposed decoder is $16.261m^2$ and the power dissipation is 198mW at a power supply voltage of 1.5V.

Low-Complexity H.264/AVC Deblocking Filter based on Variable Block Sizes (가변블록 기반 저복잡도 H.264/AVC 디블록킹 필터)

  • Shin, Seung-Ho;Doh, Nam-Keum;Kim, Tae-Yong
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.45 no.4
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    • pp.41-49
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    • 2008
  • H.264/AVC supports variable block motion compensation, multiple reference images, 1/4-pixel motion vector accuracy, and in-loop deblocking filter, compared with the existing compression technologies. While these coding technologies are major functions of compression rate improvement, they lead to high complexity at the same time. For the H.264 video coding technology to be actually applied on low-end / low-bit rates terminals more extensively, it is essential to improve tile coding speed. Currently the deblocking filter that can improve the moving picture's subjective image quality to a certain degree is used on low-end terminals to a limited extent due to computational complexity. In this paper, a performance improvement method of the deblocking filter that efficiently reduces the blocking artifacts occurred during the compression of low-bit rates digital motion pictures is suggested. In the method proposed in this paper, the image's spatial correlational characteristics are extracted by using the variable block information of motion compensation; the filtering is divided into 4 modes according to the characteristics, and adaptive filtering is executed in the divided regions. The proposed deblocking method reduces the blocking artifacts, prevents excessive blurring effects, and improves the performance about $30{\sim}40%$ compared with the existing method.

Fast Intra Prediction Mode Decision using Most Probable Mode for H.264/AVC (H.264/AVC에서의 최고 확률 모드를 이용한 고속 화면 내 예측 모드 결정)

  • Kim, Dae-Yeon;Kim, Jeong-Pil;Lee, Yung-Lyul
    • Journal of Broadcast Engineering
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    • v.15 no.3
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    • pp.380-390
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    • 2010
  • The most recent standard video codec, H.264/AVC achieves significant coding efficiency by using a rate-distortion optimization(RDO). The RDO is a measurement for selecting the best mode which minimizes the Lagrangian cost among several modes. As a result, the computational complexity is increased drastically in encoder. In this paper, a method for fast intra prediction mode decision is proposed to reduce the RDO complexity. To speed up Intra$4{\times}4$ and Chroma Intra encoding, the proposed method decides the case that MPM (Most Probable Mode) is the best prediction mode. In this case, the RDO process is skipped, and only MPM is used for encoding the block in Intra$4{\times}4$. And the proposed method is also applied to the chroma Intra prediction mode in a similar way to the Intra$4{\times}4$. The experimental results show that the proposed method achieves an average encoding time saving of about 63% with negligible loss of PSNR (Peak Signal-to-Noise Ratio).

Characteristics of Flames Propagating Through Combustible Particles Concentration in a Vertical Duct (수직 배관 내의 농도변화에 따른 분진폭발 특성)

  • Han, Ou-Sup;Han, In-Soo;Choi, Yi-Rac;Lee, Jung-Suk;Lee, Su-Hee
    • Korean Chemical Engineering Research
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    • v.49 no.1
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    • pp.41-46
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    • 2011
  • We investigated experimentally the properties of dust explosion through lycopodium particle clouds in a duct to provide the fundamental knowledge. Propagating dust flames in the vertical duct of 120 cm height and 12 cm square cross-section were observed by digital video camera and flame front is visualized using by PIV(Particle Image Velocimetry) system. As the result, when the same average dust concentration existed in the vertical duct, downward flame propagation was faster than the upward flame propagation, its rate increased with dust concentration in 300g/$m^3$. Post flames were caused by the ignition of unburned particles which flowed into the rear region of flame from passage between flame and duct wall, and they generated regardless of duct condition. Also, it was found that appearance frequency of post flames during dust flame propagations increased with the increase of dust concentration.