• Title/Summary/Keyword: Video Image

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Towards 3D Modeling of Buildings using Mobile Augmented Reality and Aerial Photographs (모바일 증강 현실 및 항공사진을 이용한 건물의 3차원 모델링)

  • Kim, Se-Hwan;Ventura, Jonathan;Chang, Jae-Sik;Lee, Tae-Hee;Hollerer, Tobias
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.46 no.2
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    • pp.84-91
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    • 2009
  • This paper presents an online partial 3D modeling methodology that uses a mobile augmented reality system and aerial photographs, and a tracking methodology that compares the 3D model with a video image. Instead of relying on models which are created in advance, the system generates a 3D model for a real building on the fly by combining frontal and aerial views. A user's initial pose is estimated using an aerial photograph, which is retrieved from a database according to the user's GPS coordinates, and an inertial sensor which measures pitch. We detect edges of the rooftop based on Graph cut, and find edges and a corner of the bottom by minimizing the proposed cost function. To track the user's position and orientation in real-time, feature-based tracking is carried out based on salient points on the edges and the sides of a building the user is keeping in view. We implemented camera pose estimators using both a least squares estimator and an unscented Kalman filter (UKF). We evaluated the speed and accuracy of both approaches, and we demonstrated the usefulness of our computations as important building blocks for an Anywhere Augmentation scenario.

Evaluation of marginal fidelity of copy-milled and CAD/CAM all ceramic crowns

  • Jeong Seung-Mi;Kang Dong-Wan;Wolf Christoph
    • The Journal of Korean Academy of Prosthodontics
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    • v.39 no.3
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    • pp.243-249
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    • 2001
  • Statement of the problem. The interest in all-ceramic restorations has increased as more techniques have become available. With the introduction of machinable dental ceramics and CAD/CAM systems or Copy-milling systems there is a need for evaluating the quality levels of these new fabrication techniques. Purpose. This study was to evaluate the fitting accuracy of machined all-ceramic crowns made out of an industrially prefabricated feldspathic porcelain. Material and Methods. Three master models with different cutting depth (0.8mm/1.0mm/1.2mm)were produced using a palladium-silver alloy. A total of 36 working dies, 12 of each form, was used for the modellation of prototype resin copings and 36 additional crowns, 12 of each cutting depth, were produced by using the $CEREC^{(R)}2$ system for all crowns. The maginal fit of all 72 crowns was then evaluated on their respective master die at 54 circularly staggered points of measurement per crown under a fixation pressure of 30 N by using a computerized video image system. Results. The medians of the copy-milled $CELAY^{(R)}$ crowns ranged from 29 to $36{\mu}m$. The highest value for the marginal gap was found in group B (cutting depth 1.0mm) at $107{\mu}m$. The median for the $CEREC^{(R)}2$ crowns was found between 43.5 and $70{\mu}m$. The maximum values for all three groups ranged from $181{\mu}m$ to $286{\mu}m$. With $286{\mu}m$ the highest value for marginal gap was found in group C. the Kruskal-Wallis test and multiple comparisons analysis procedure revealed a significant influence of the production technique on the marginal fit in all three groups (p<0,02). Conclusion. 1. The $CELAY^{(R)}$ system is capable to produce all-ceramic crowns with a significantly better marginal fit than the $CEREC^{(R)}2$ system. 2. As far as premolar crowns produced with the $CEREC^{(R)}2$ system are concerned, the cutting depth has a significant influence on fitting accuracy. 3. The production of crowns with an acceptable marginal fit is possible with both systems. However, adhesive luting is recommended for milled feldspathic porcelain crowns.

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A Study on Motion Estimator Design Using DCT DC Value (DCT 직류 값을 이용한 움직임 추정기 설계에 관한 연구)

  • Lee, Gwon-Cheol;Park, Jong-Jin;Jo, Won-Gyeong
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.38 no.3
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    • pp.258-268
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    • 2001
  • The compression method is necessarily used to send the high quality moving picture that contains a number of data in image processing. In the field of moving picture compression method, the motion estimation algorithm is used to reduce the temporal redundancy. Block matching algorithm to be usually used is distinguished partial search algorithm with full search algorithm. Full search algorithm be used in this paper is the method to compare the reference block with entire block in the search window. It is very efficient and has simple data flow and control circuit. But the bigger the search window, the larger hardware size, because large computational operation is needed. In this paper, we design the full search block matching motion estimator. Using the DCT DC values, we decide luminance. And we apply 3 bit compare-selector using bit plane to I(Intra coded) picture, not using 8 bit luminance signals. Also it is suggested that use the same selective bit for the P(Predicted coded) and B(Bidirectional coded) picture. We compare based full search method with PSNR(Peak Signal to Noise Ratio) for C language modeling. Its condition is the reference block 8$\times$8, the search window 24$\times$24 and 352$\times$288 gray scale standard video images. The result has small difference that we cannot see. And we design the suggested motion estimator that hardware size is proved to reduce 38.3% for structure I and 30.7% for structure II. The memory is proved to reduce 31.3% for structure I and II.

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A Prediction Search Algorithm by using Temporal and Spatial Motion Information from the Previous Frame (이전 프레임의 시공간 모션 정보에 의한 예측 탐색 알고리즘)

  • Kwak, Sung-Keun;Wee, Young-Cheul;Kimn, Ha-Jine
    • Journal of the Korea Computer Graphics Society
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    • v.9 no.3
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    • pp.23-29
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    • 2003
  • There is the temporal correlation of the video sequence between the motion vector of current block and the motion vector of the previous block. If we can obtain useful and enough information from the motion vector of the same coordinate block of the previous frame, the total number of search points used to find the motion vector of the current block may be reduced significantly. In this paper, we propose the block-matching motion estimation using an adaptive initial search point by the predicted motion information from the same block of the previous frame. And the first search point of the proposed algorithm is moved an initial point on the location of being possibility and the searching process after moving the first search point is processed according to the fast search pattern. Simulation results show that PSNR(Peak-to-Signal Noise Ratio) values are improved UP to the 1.05dB as depend on the image sequences and improved about 0.33~0.37dB on an average. Search times are reduced about 29~97% than the other fast search algorithms. Simulation results also show that the performance of the proposed scheme gives better subjective picture quality than the other fast search algorithms and is closer to that of the FS(Full Search) algorithm.

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Development of Fall Prevention Program for Improvement of Healthcare in Rehabilitation Patients Based on Image Processing : A Preliminary Investigation (영상처리 기반 재활 환자의 헬스케어 개선을 위한 낙상예방 프로그램 개발 : 예비연구)

  • Kang, So-La;Yoon, Jung-Dae;Yoo, Jin-Won;Na, Chang-Ho;Heo, Sung-Jin;Kim, Ye-Soon;Moon, Jong-Hoon
    • The Journal of the Korea institute of electronic communication sciences
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    • v.13 no.4
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    • pp.887-896
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    • 2018
  • The purpose of this preliminary study was to investigate the effect of fall prevention program on the occurrence of falls in inpatients at general hospital. Before the intervention, we identified the occurrence of the rate of falls in I hospital at Incheon and 190 patients received rehabilitation treatment. The causes of falls were carelessness of caregivers and therapists, increased burden of therapists, and height of beds. After recognizing the problems, the authors developed a fall prevention program through the PDCA model. The fall prevention program consisted of a video of fall prevention education and education for the patients and caregivers, environmental improvement and education of therapists for two months. After intervention, 230 patients were subjected to be included as analysis of the incidence of falls included As a result, the fall incidence was reduced by 34.1~66.7% in the pain clinic and 21.3~40.8% in the exercise clinic / department of occupational therapy compared to the before intervention. These findings show that the fall prevention program has a positive effect on the fall of inpatients, and it can be used as a model for fall prevention.

Implementation of Character and Object Metadata Generation System for Media Archive Construction (미디어 아카이브 구축을 위한 등장인물, 사물 메타데이터 생성 시스템 구현)

  • Cho, Sungman;Lee, Seungju;Lee, Jaehyeon;Park, Gooman
    • Journal of Broadcast Engineering
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    • v.24 no.6
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    • pp.1076-1084
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    • 2019
  • In this paper, we introduced a system that extracts metadata by recognizing characters and objects in media using deep learning technology. In the field of broadcasting, multimedia contents such as video, audio, image, and text have been converted to digital contents for a long time, but the unconverted resources still remain vast. Building media archives requires a lot of manual work, which is time consuming and costly. Therefore, by implementing a deep learning-based metadata generation system, it is possible to save time and cost in constructing media archives. The whole system consists of four elements: training data generation module, object recognition module, character recognition module, and API server. The deep learning network module and the face recognition module are implemented to recognize characters and objects from the media and describe them as metadata. The training data generation module was designed separately to facilitate the construction of data for training neural network, and the functions of face recognition and object recognition were configured as an API server. We trained the two neural-networks using 1500 persons and 80 kinds of object data and confirmed that the accuracy is 98% in the character test data and 42% in the object data.

Modeling of Visual Attention Probability for Stereoscopic Videos and 3D Effect Estimation Based on Visual Attention (3차원 동영상의 시각 주의 확률 모델 도출 및 시각 주의 기반 입체감 추정)

  • Kim, Boeun;Song, Wonseok;Kim, Taejeong
    • Journal of KIISE
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    • v.42 no.5
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    • pp.609-620
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    • 2015
  • Viewers of videos are likely to absorb more information from the part of the screen that attracts visual attention. This fact has led to the visual attention models that are being used in producing and evaluating videos. In this paper, we investigate the factors that are significant to visual attention and the mathematical form of the visual attention model. We then estimated the visual attention probability using the statistical design of experiments. The analysis of variance (ANOVA) verifies that the motion velocity, distance from the screen, and amount of defocus blur affect human visual attention significantly. Using the response surface modeling (RSM), we created a visual attention score model that concerns the three factors, from which we calculate the visual attention probabilities (VAPs) of image pixels. The VAPs are directly applied to existing gradient based 3D effect perception measurement. By giving weights according to our VAPs, our algorithm achieves more accurate measurement than the existing method. The performance of the proposed measurement is assessed by comparing them with subjective evaluation as well as with existing methods. The comparison verifies that the proposed measurement outperforms the existing ones.

A H.264 based Selective Fine Granular Scalable Coding Scheme (H.264 기반 선택적인 미세입자 스케일러블 코딩 방법)

  • 박광훈;유원혁;김규헌
    • Journal of KIISE:Computing Practices and Letters
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    • v.10 no.4
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    • pp.309-318
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    • 2004
  • This paper proposes the H.264-based selective fine granular scalable (FGS) coding scheme that selectively uses the temporal prediction data in the enhancement layer. The base layer of the proposed scheme is basically coded by the H.264 (MPEG-4 Part 10 AVC) visual coding scheme that is the state-of-art in codig efficiency. The enhancement layer is basically coded by the same bitplane-based algorithm of the MPEG-4 (Part 2) fine granular scalable coding scheme. In this paper, we introduce a new algorithm that uses the temproal prediction mechanism inside the enhancement layer and the effective selection mechanism to decide whether the temporally-predicted data would be sent to the decoder or not. Whenever applying the temporal prediction inside the enhancement layer, the temporal redundancies may be effectively reduced, however the drift problem would be severly occurred especially at the low bitrate transmission, due to the mismatch bewteen the encoder's and decoder's reference frame images. Proposed algorithm selectively uses the temporal-prediction data inside the enhancement layer only in case those data could siginificantly reduce the temporal redundancies, to minimize the drift error and thus to improve the overall coding efficiency. Simulation results, based on several test image sequences, show that the proposed scheme has 1∼3 dB higher coding efficiency than the H.264-based FGS coding scheme, even 3∼5 dB higher coding efficiency than the MPEG-4 FGS international standard.

A Study on Yi Sang Representation in Media -Focusing on the cinema and the drama (영상매체에 형상화 된 시인 '이상' 표상 연구 -영화 <건축무한육면각체의 비밀>, 드라마 <이상 그 이상>을 중심으로)

  • Son, Mi-young
    • The Journal of the Convergence on Culture Technology
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    • v.5 no.4
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    • pp.29-36
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    • 2019
  • Lee Sang's poems and his portraits are being used in various video media. Depending on the characteristics of the medium and genre, the representation of the poet or higher and his poems are selected and variations in different ways. In a modern era where literature communicates with various media, reviewing how a poet's portrait is shaped is also the process of reading what text wants to convey to the public through a single person. This study examined aspects in which representations of poets or higher were utilized in various image media, and compared and analyzed how poet aberrations are represented in each text. In particular, the discussion centered on the movie and the drama . In the movie , the above poem is used as a hidden puzzle. The film uses the popularly known 'genius' representation to track down Yi Sang's secret. Because of this, the film represents its ideal in a way that is faithful to the genre's custom of Thriller In comparison, the drama was about to re-emerge as a young man with a passion for the inner workings. The cynical attitude shown in the above text is also a reflection of the love for the nation and the times. These different typographical methods are worth noting in terms of the literary man's public perception of "Yi-sang" and the strategy of the new portrait attempt.

Epic Theatre Reexamined from the Viewpoint of Cognitive Science (인지과학의 관점에서 본 서사극 이론)

  • Kim, Yongsoo
    • Journal of Korean Theatre Studies Association
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    • no.49
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    • pp.133-169
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    • 2013
  • Reexamining Brecht's theoretical hypotheses in terms of cognitive science, this essay arrived at several temporary interpretations. Cognitive science implies that empathy can precede the rational understanding in Verfremdungseffekt. The spectator tends to simulate the unfamiliar incident and character and feels the consequential embodied emotion that leads to the cognitive understanding. The similar situation can be found in social gestus. According to cognitive science, gesture(social gestus) is simulated in the mirror-neuron of spectator, arousing consequently the embodied emotion that triggers the succeeding understanding. The spectator apts to experience and feel physically the moving gesture before decoding it as a social signification. Brecht's intention that attempts to reveal the duality of actor and character by eliminating the fourth wall is negated by cognitive science. According to the theory of conceptual blending, the spectator under the eliminated fourth wall mixes actor and character, and simulates this blending image so that he experiences it imaginatively. As such, another kind of illusion can be formed when a fourth wall is collapsed. Meanwhile, the critical thinking of spectator Brecht wanted can be hard to occur during the performance. It is necessary for the spectator to recollect the bygone dialogue and action in terms of social context as if he presses the pause, stopping the playback while watching a play in video. In this respect the social meaning Brecht intended can be achieved more effectively by the stop motion like tableau. It would not only give the time for the spectator to consider the implied social signification, but also make him possible to decode a semiotic meaning as if interpreting a still picture. Or it can be delivered by the dialogue that expresses the playwright's critical judgement. In this case, the subject of critical thinking is not the spectator but the author. The alternative explanation that the cognitive science suggests illuminates theoretically the reasons why Brecht's theory fails to be realized in practice. In a sense, Brecht's theory is nothing but a theoretical hypothesis. It takes the premise that the emotion hinders the rational thinking, understanding emotion and reason oppositively like Plato. This assumption is negated easily by the recent cognitive science that sees the reason as a by-product of physical experience including emotion. The rational understanding, in this sense, begins from the embodied emotion. As such the cognitive science denies the dichotomy of emotion and reason that Brecht adopted. The theoretical hypothesis of cognitive science makes us recognize again the importance of bodily experience in theatre. In theatre the spectator tends to experience physically before decoding the intellectual meaning. The spectator Brecht wanted, therefore, is far from the reality. The spectator usually experiences and reacts physically before decoding the meaning critically. Thus Brecht's intention can be realized by the embodied emotion resulted from simulation. This tentative interpretation suggests that we need to pay more attention to the empirical study of spectatorship, not remaining in a speculative study.