• Title/Summary/Keyword: Frames

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An Improved key Frame Selection Algorithm Based on Histogram Difference Between Frames (프레임간 히스토그램 차이를 이용한 개선된 대표프레임 추출 알고리즘)

  • 정지현;전승철;박성한
    • Proceedings of the IEEK Conference
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    • 2000.11c
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    • pp.137-140
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    • 2000
  • In this paper, we propose as new algorithm for the selection of key frames in a given video. For the selected key frames to be well defined, the selected key frames need to spread out on the whole temporal domain of the given video and guaranteed not to be duplicate. For this purpose, we take the first frame of each shot of the video as the candidate key frame to represent the video. To reduce the overall processing time, we eliminate some candidate key frames which are visually indistinct in the histogram difference. The key frames are then selected using a clustering processing based on the singly linked hierarchical tree. To make the selected key frames be distributed evenly on the whole video, the deviation and time difference between the selected key frames are used. The simulation results demonstrate that our method provides the better performance compared with previous methods.

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Key Frame Extraction using Shot Coverage and Distortion (샷 기여도와 왜곡률을 고려한 키 프레임 추출 알고리즘)

  • 이중용;문영식
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.40 no.3
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    • pp.137-143
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    • 2003
  • Key frame extraction has been recognized as one of tile important research issues in video information retrieval. Although progress has been made in key frame extraction, the existing approaches do not evaluate the importance of extracted frame Quantitatively, and Dey are computationally expensive or ineffective. In this Paper, we introduce a new 미해rithm for key frame extraction using shot coverage and distortion. The algorithm finds significant key frames from candidate key frames. When selecting the candidate frames, the coverage rate to the total frames from each frame is computed by using the difference between the adjacent frames in tile shot. The frames within 10$\%$ from the top are selected as the candidates. Then, by comfuting the distortion rate of the candidates against all frames, pick the frames which arc most representative are selected. The performance of the proposed algorithm has been verified by a statistical test. Experiments show that more than 13-50$\%$ improvement has been obtained by the proposed algorithm compared to the existing methods.

A New Framework for Automatic Extraction of Key Frames Using DC Image Activity

  • Kim, Kang-Wook
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.12
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    • pp.4533-4551
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    • 2014
  • The effective extraction of key frames from a video stream is an essential task for summarizing and representing the content of a video. Accordingly, this paper proposes a new and fast method for extracting key frames from a compressed video. In the proposed approach, after the entire video sequence has been segmented into elementary content units, called shots, key frame extraction is performed by first assigning the number of key frames to each shot, and then distributing the key frames over the shot using a probabilistic approach to locate the optimal position of the key frames. Moreover, we implement our proposed framework in Android to confirm the validity, availability and usefulness. The main advantage of the proposed method is that no time-consuming computations are needed for distributing the key frames within the shots and the procedure for key frame extraction is completely automatic. Furthermore, the set of key frames is independent of any subjective thresholds or manually set parameters.

The beneficial effects of beam web opening in seismic behavior of steel moment frames

  • Erfani, Saeed;Naseri, Ata Babazadeh;Akrami, Vahid
    • Steel and Composite Structures
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    • v.13 no.1
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    • pp.35-46
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    • 2012
  • Implementation of openings in beams web has been introduced as an innovative method for improving seismic performance of steel moment frames. In this paper, several steel moment frames have been studied in order to evaluate the effect of openings in beams web. The beam sections with web opening have been modeled as a simplified super-element to be used in designing frames and to determine opening configurations. Finite element models of designed frames were generated and nonlinear static pushover analysis was conducted. The efficient location for openings along the beam length was discovered and the effects of beams with web openings on local and global behavioral characteristics of frames were discussed. Base on the results, seismic performance of steel moment frames was improved by creating openings in beams web, in terms of reduction in stress level of frame sensitive areas such as beam to column connections and panel zones.

φ-FRAMES AND φ-RIESZ BASES ON LOCALLY COMPACT ABELIAN GROUPS

  • Gol, Rajab Ali Kamyabi;Tousi, Reihaneh Raisi
    • Journal of the Korean Mathematical Society
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    • v.48 no.5
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    • pp.899-912
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    • 2011
  • We introduce ${\varphi}$-frames in $L^2$(G), as a generalization of a-frames defined in [8], where G is a locally compact Abelian group and ${\varphi}$ is a topological automorphism on G. We give a characterization of ${\varphi}$-frames with regard to usual frames in $L^2$(G) and show that ${\varphi}$-frames share several useful properties with frames. We define the associated ${\varphi}$-analysis and ${\varphi}$-preframe operators, with which we obtain criteria for a sequence to be a ${\varphi}$-frame or a ${\varphi}$-Bessel sequence. We also define ${\varphi}$-Riesz bases in $L^2$(G) and establish equivalent conditions for a sequence in $L^2$(G) to be a ${\varphi}$-Riesz basis.

Use of SMA bars to enhance the seismic performance of SMA braced RC frames

  • Meshaly, Mohamed E.;Youssef, Maged A.;Abou Elfath, Hamdy M.
    • Earthquakes and Structures
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    • v.6 no.3
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    • pp.267-280
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    • 2014
  • Shape Memory Alloy (SMA) braces can be used to reduce seismic residual deformations observed in steel braced Reinforced Concrete (RC) frames. To further enhance the seismic performance of these frames, the use of SMA bars to reinforce their beams is investigated in this paper. Three-story and nine-story SMA-braced RC frames are designed utilizing regular steel reinforcing bars. Their seismic performance is examined using twenty seismic ground motions. The frames are then re-designed using SMA reinforcing bars. Different design alternatives representing different locations for the SMA reinforcing bars are considered. The optimum locations for the SMA bars are identified after analysing the design alternatives. The seismic performance of these frames has indicated better deformability when SMA bars are used in the beams.

Drift Control for Multistory Moment Frames under Lateral Loading

  • Grigorian, Carl E.;Grigorian, Mark
    • International Journal of High-Rise Buildings
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    • v.2 no.4
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    • pp.355-365
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    • 2013
  • The paper reports results of recent studies on the effects of column support conditions on the lateral displacements of moment frames at incipient collapse. The article presents a number of exercises in the plastic theory of structures that lead to useful design formulae. It has been shown that Drift Shifting (DS) is caused due to differences in the stiffnesses of adjoining columns, and that changes in drift ratios are more pronounced at first level column joints in both fixed as well as pinned base frames. In well proportioned moment frames, DS in the upper levels could be minimized, even reduced to zero. It has been demonstrated that DS can be eliminated in properly designed fixed and grade beam supported (GBS) moment frames. Several examples, including symbolic P-delta effects, have been provided to demonstrate the validity and the applications of the proposed ideas to the design and drift control of moment frames. The proposed methodology is exact within the bounds of the theoretical assumptions and is well suited for preliminary design and teaching purposes.

Behavior of Multiple Vinyl House Frames Reinforced by Steel Wire (강선으로 보강된 연동형 비닐하우스 골조의 구조거동)

  • Jung, Dong Jo;Kim, Jin;Seo, Yun Soo
    • Journal of the Korean Institute of Rural Architecture
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    • v.18 no.3
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    • pp.35-42
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    • 2016
  • For the reason of economy, farmers and structural engineers prefer the vinyl house frame members that have the lightest cross sections. Therefore, in order to reach this aim, rod bracing system is the best method for multiple vinyl house frames. In this study, wire rods (tension members) are used to be bracing members in multiple vinyl house frames. The effects of additional wire rods in the frames are investigated by the variations of the bending moments, axial forces, displacements and combined stresses in the main frames that are reinforced by different shapes of rod bracing system. Vinyl house frames are usually made by steel pipe members and collapsed by the excessive wind and snow loads. Two kinds of bracing models are used for wind and snow loads separately in this study. The effective bracing models for each load are finally figured out.

Effect of semi-rigid connections in improvement of seismic performance of steel moment-resisting frames

  • Feizi, M. Gholipour;Mojtahedi, A.;Nourani, V.
    • Steel and Composite Structures
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    • v.19 no.2
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    • pp.467-484
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    • 2015
  • Seismic performances of dual steel moment-resisting frames with mixed use of rigid and semi-rigid connections were investigated to control of the base shear, story drifts and the ductility demand of the elements. To this end, nonlinear seismic responses of three groups of frames with three, eight and fifteen story were evaluated. These frames with rigid, semi-rigid and combined configuration of rigid and semi-rigid connections were analyzed under five earthquake records and their responses were compared in ultimate limit state of rigid frame. This study showed that in all frames, it could be found a state of semi-rigidity and connections configuration which behaved better than rigid frame, with consideration of the base shear and story drifts criterion. Finally, some criteria were suggested to locate the best place of the semi-rigid connections for improvement of the seismic performance of steel moment-resisting frames.

Convert 2D Video Frames into 3D Video Frames (2차원 동영상의 3차원 동영상 변화)

  • Lee, Hee-Man
    • Journal of the Korea Society of Computer and Information
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    • v.14 no.6
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    • pp.117-123
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    • 2009
  • In this paper, An algorithm which converts 2D video frames into 3D video frames of parallel looking stereo camea is proposed. The proposed algorithm finds the disparity information between two consecutive video frames and generates 3D video frames from the obtained disparity maps. The disparity information is obtained from the modified iterative convergence algorithm. The method of generating 3D video frames from the disparity information is also proposed. The proposed algorithm uses coherence method which overcomes the video pattern based algorithms.