• Title/Summary/Keyword: view selection

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Efficient Top-k Query Processing Algorithm Using Grid Index-based View Selection Method (그리드 인덱스 기반 뷰 선택 기법을 이용한 효율적인 Top-k 질의처리 알고리즘)

  • Hong, Seungtae;Youn, Deulnyeok;Chang, Jae Woo
    • KIISE Transactions on Computing Practices
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    • v.21 no.1
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    • pp.76-81
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    • 2015
  • Research on top-k query processing algorithms for analyzing big data have been spotlighted recently. However, because existing top-k query processing algorithms do not provide an efficient index structure, they incur high query processing costs and cannot support various types of queries. To solve these problems, we propose a top-k query processing algorithm using a view selection method based on a grid index. The proposed algorithm reduces the query processing time by retrieving the minimum number of grid cells for the query range, by using a grid index-based view selection method. Finally, we show from our performance analysis that the proposed scheme outperforms an existing scheme, in terms of both query processing time and query result accuracy.

Quantization Parameter Selection Method For H.264-based Multi-view Video Coding (H.264 기반 다시점 비디오 부호화를 위한 양자화 계수 결정 방법)

  • Park, Pil-Kyu;Ho, Yo-Sung
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.6C
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    • pp.579-584
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    • 2007
  • Recently various prediction structures have been proposed to exploit inter-view correlation among multi-view video sequences. In this paper, we propose a QP(quantization parameter) selection method for the B frame inserted in the first frames of each GOP(group of pictures), where we change QP for the B frame adaptively to achieve uniform picture quality and overall coding gain. Each B frame is coded with reference to two frames in its adjacent views. We calculate QP for the B frame based on the correlation between the two reference frames, calculated using their rate-distortion costs. By applying the proposed method to the MVC reference prediction structure, we have improved the coding gain by 0.09$\sim$0.16 dB.

Behrens-Fisher Problem from a Model Selection Point of View

  • Jeon, Jong-Woo;Lee, Kee-Won
    • Journal of the Korean Statistical Society
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    • v.20 no.2
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    • pp.99-107
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    • 1991
  • Behrens-Fisher problem is viewed from a model selection approach. Normal distribution is regarded as an approximating model, A criterion, called TIC, is derived and is compared with selection criteria such as AIC and a bootstrap estimator. Stochastic approximation is used since no closed form expression is available for the bootstrap estimator.

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Fast and Accurate Visual Place Recognition Using Street-View Images

  • Lee, Keundong;Lee, Seungjae;Jung, Won Jo;Kim, Kee Tae
    • ETRI Journal
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    • v.39 no.1
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    • pp.97-107
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    • 2017
  • A fast and accurate building-level visual place recognition method built on an image-retrieval scheme using street-view images is proposed. Reference images generated from street-view images usually depict multiple buildings and confusing regions, such as roads, sky, and vehicles, which degrades retrieval accuracy and causes matching ambiguity. The proposed practical database refinement method uses informative reference image and keypoint selection. For database refinement, the method uses a spatial layout of the buildings in the reference image, specifically a building-identification mask image, which is obtained from a prebuilt three-dimensional model of the site. A global-positioning-system-aware retrieval structure is incorporated in it. To evaluate the method, we constructed a dataset over an area of $0.26km^2$. It was comprised of 38,700 reference images and corresponding building-identification mask images. The proposed method removed 25% of the database images using informative reference image selection. It achieved 85.6% recall of the top five candidates in 1.25 s of full processing. The method thus achieved high accuracy at a low computational complexity.

A Study on the Site Selection and Orientation of Western House in Cheongju (청주(淸州) 탑동양관(塔洞洋館)의 입지선정(立地選定) 및 좌향(坐向)에 관한 연구(硏究))

  • Seo, Hyang-Soon;Lee, Min-Kyoung;Kim, Tai-Young
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2008.04a
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    • pp.197-202
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    • 2008
  • The purpose of this study is to clarify the site selection and orientation which have affected the western missionaries in construction of the first western house in Cheongju area. The results of this study are as follows; In the site selection, they chose Tap-Dong hill, by finding the higher position and taking a fine view of all natural elements, because the alters like the tomb of Confucius, the existing settlement Godang village, Dang Mt. are already located around this area. And also it was that they could easily go into Tap-Dong hill through the existing alleys, These alleys, generated near the original road of Tap-Dong hill, are developed to modern road system. These alleys affect western house's entrance and orientation. In deciding the orientation of house, korean people prefer to south and east by considering Feng-shui theory; otherwise western house, specially the first house has a southwestern aspect, because the western missionaries have a preference for the topography, entry, and view than a house facing south.

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Comparisons Between Model Selection Criteria

  • Choongrak Kim;Hyoungsoon Kim;Meeseon Jeong
    • Communications for Statistical Applications and Methods
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    • v.4 no.1
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    • pp.11-19
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    • 1997
  • One of the most important issues in regression is variable selection problem. Recently several methods have been proposed to overcome the overparameterization property of Mallow's $C_p$. In this paper we compare these model selection criteria in view of the performance of selecting true model by simulation study.

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Integrating Multi-view Stereoscopic Transmission System into MPEG-21 DIA (Digital Item Adaptation)

  • Lee, Seung-Won;Kim, Man-Bae;Byun, Hye-Ran;Park, Il-Kwon
    • Journal of Broadcast Engineering
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    • v.12 no.4
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    • pp.342-349
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    • 2007
  • In general multi-view system, all the view sequences acquired at the server are transmitted to the client. However, this kind of system requires high processing power of the server as well as the client, thus it is posing a difficulty in practical applications. To overcome this problem, a relatively simple method is to transmit only two view-sequences requested by the client in order to deliver a stereoscopic video. In this system, effective communication between the server and the client is one of important aspects. Therefore, we propose an efficient multi-view system that transmits two view-sequences according to user's request. The view selection process is integrated into MPEG-21 DIA (Digital Item Adaptation) so that our system is compatible to MPEG-21 multimedia framework. Furthermore, multi-view descriptors related to multi-view camera and systems are newly introduced. The syntax of the descriptions and their elements is represented in XML (extensible Markup Language) schema. Intermediate view reconstruction (IVR) is used to reduce such discomfort with excessive disparity. Furthermore, IVR is useful for smooth transition between two stereoscopic view sequences. Finally, through the implementation of testbed, we can show the valuables and possibilities of our system.

User-created multi-view video generation with portable camera in mobile environment (모바일 환경의 이동형 카메라를 이용한 사용자 저작 다시점 동영상의 제안)

  • Sung, Bo Kyung;Park, Jun Hyoung;Yeo, Ji Hye;Ko, Il Ju
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.8 no.1
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    • pp.157-170
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    • 2012
  • Recently, user-created video shows high increasing in production and consumption. Among these, videos records an identical subject in limited space with multi-view are coming out. Occurring main reason of this kind of video is popularization of portable camera and mobile web environment. Multi-view has studied in visually representation technique fields for point of view. Definition of multi-view has been expanded and applied to various contents authoring lately. To make user-created videos into multi-view contents can be a kind of suggestion as a user experience for new form of video consumption. In this paper, we show the possibility to make user-created videos into multi-view video content through analyzing multi-view video contents even there exist attribute differentiations. To understanding definition and attribution of multi-view classified and analyzed existing multi-view contents. To solve time axis arranging problem occurred in multi-view processing proposed audio matching method. Audio matching method organize feature extracting and comparing. To extract features is proposed MFCC that is most universally used. Comparing is proposed n by n. We proposed multi-view video contents that can consume arranged user-created video by user selection.

A Hybrid Method for Improvement of Evolutionary Computation (진화 연산의 성능 개선을 위한 하이브리드 방법)

  • Chung, Jin-Ki;Oh, Se-Young
    • Journal of the Korean Institute of Intelligent Systems
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    • v.12 no.4
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    • pp.317-322
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    • 2002
  • The major operations of Evolutionary Computation include crossover, mutation, competition and selection. Although selection does not create new individuals like crossover or mutation, a poor selection mechanism may lead to problems such as taking a long time to reach an optimal solution or even not finding it at all. In view of this, this paper proposes a hybrid Evolutionary Programming (EP) algorithm that exhibits a strong capability to move toward the global optimum even when stuck at a local minimum using a synergistic combination of the following three basic ideas. First, a "local selection" technique is used in conjunction with the normal tournament selection to help escape from a local minimum. Second, the mutation step has been improved with respect to the Fast Evolutionary Programming technique previously developed in our research group. Finally, the crossover and mutation operations of the Genetic Algorithm have been added as a parallel independent branch of the search operation of an EP to enhance search diversity.

A Synchronized Multiplexing Scheme for Multi-view HD Video Transport System over IP Networks (실시간 다시점 고화질 비디오 전송 시스템을 위한 동기화된 다중화 기법)

  • Kim, Jong-Ryool;Kim, Jong-Won
    • Journal of Broadcast Engineering
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    • v.13 no.6
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    • pp.930-940
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    • 2008
  • This paper proposes a prototype realization of multi-view HD video transport system with synchronized multiplexing over IP networks. The proposed synchronized multiplexing considers the synchronization during video acquisition and the multiplexing for the interactive view-selection during transport. For the synchronized acquisition from multiple HDV camcorders through IEEE 1394 interface, we estimate the timeline differences among MPEG-2 compressed video streams by using global time of network between the cameras and a server and correct timelines of video streams by changing the time stamp of the MPEG-2 system stream. Also, we multiplex a selected number of acquired HD views at the MPEG-2 TS (transport stream) level for the interactive view-selection during transport. Thus, with the proposed synchronized multiplexing scheme, we can display synchronized HD view.