1,721,073 research outputs found
다장면 비국부 매팅 라플라시안을 이용한 영상 매팅
No full text학위논문(석사) - 한국과학기술원 : 전산학과, 2012.2, [ iii, 24 p. ]We present an approach to extract high quality temporally coherennt alpha mattes of objects from a video. Our approach extends the conventional matting approach, i.e. closed form matting, to video by using multi-frame nonlocal matting Laplacian. Our multi-frame nonlocal matting Laplacian is defifined over a nonlocal neighborhood in the spatio-temporal domain of video by evaluating color and texture similarity between pixels in a video sequence. Hence, the temporal coherence is explicitly encoded in the multi-frame nonlocal matting Laplacian. We have also proposed methods for speeding up the video matting process and applying the nonlocal mean regularization to further enhance the temporal coherence. Our proposed approach is robust even for the scenes with complicated background. We demonstrate the effectiveness of our proposed approach on various examples with qualitative comparisons
to the results from the previous matting algorithms.한국과학기술원 : 전산학과
고해상도의 라이트 필드 영상 구성을 위한 리트로 카메라 캘리브레이션 파이프라인 모델링 기법 연구
No full text학위논문(석사) - 한국과학기술원 : 전산학과, 2014.2, [ iii, 32 p. ]Light-field imaging systems have got much attention recently as the next generation camera model. A light-field imaging system consists of three parts: data acquisition,manipulation, and application. Given an acquisition system, it is important to understand how a light-field camera converts from its raw image to its resulting refocused image. In this paper, using the Lytro camera as an example, we describe step-by-step procedures to calibrate a raw light-field image. In particular, we are interested in knowing the spatial and angular coordinates of the micro lens arrayand the resampling process for image reconstruction. Since Lytro use hexagonal arrangement of a micro lens image, additional treatments in calibration are required. After calibration, we analyze and compare the performances of severalresampling methods for image reconstruction with and without calibration. Finally, a learning based interpolation method is proposed which demonstrates a higher resolutionimage reconstruction than previous interpolation methods including method used in Lytro software. To this end, we have also revealed additional processes, e.g. defected pixel removal, color correction, noise reduction and rectification, in thecalibration pipeline which further enhance quality of reconstructed light field image to meet consumer level standards.한국과학기술원 : 전산학과
국부 영역 추적 기법을 이용한 비강체 물체 추적 알고리즘 연구
No full text학위논문(석사) - 한국과학기술원 : 조천식녹색교통대학원, 2015.8
,[vi, 42 p. :]교통 시스템이 더욱 체계화 되고 자동화됨에 따라, 차량비전과 교통 감시 시스템과 같은 총체적인 교통 시스템에 대하여 영상 추적 기술이 중요한 역할을 할 것이라고 기대하고 있다. 본 논문에서는, 영상 시퀀스에서 비강체 물체를 추적하는 알고리즘 연구에 대하여 기술한다. 본 논문에서 제안하는 알고리즘의 핵심은 객체의 국부영역 추적이라고 할 수 있다. 추적 물체를 여러 개의 국부 영역으로 나눈 후, 일반적인 베이시안 프레임워크를 이용하여 각 국부 영역을 독립적으로 추적한다. 제안하는 알고리즘의 측정 모델은 각 로컬 패치의 연대기적 타깃 템플릿들과 현재 프레임에서의 후보 샘플들 간의 low-rank 기반 일치성 판정 방식을 이용한다. 이와 같은 방법은 각각의 국부 영역을 신뢰성 있게 추적할 수 있다. 현재 프레임에서 추정된 각각의 로컬 패치들을 대상으로 신뢰성 판정을 한다. 신뢰성이 낮다고 판단되는 로컬 패치는 제거하게 되며, 해당 영역 부근에 새로운 로컬 패치를 생성한다. 본 논문에서는 다양한 실험을 통하여 제안하는 추적 알고리즘이 최근 제안된 추적 알고리즘에 비해 탁월한 추적 성능을 지녔음을 보여준다. 본 연구를 통하여, 우리의 연구가 교통 시스템을 위한 영상 추적의 다양한 활용을 발전시키는데 근본적인 아이디어를 제시할 수 있기를 기대한다.한국과학기술원 :조천식녹색교통대학원
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
- …
