• 제목/요약/키워드: Viewpoint Change

검색결과 457건 처리시간 0.025초

Affine Local Descriptors for Viewpoint Invariant Face Recognition

  • Gao, Yongbin;Lee, Hyo Jong
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2014년도 춘계학술발표대회
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    • pp.781-784
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    • 2014
  • Face recognition under controlled settings, such as limited viewpoint and illumination change, can achieve good performance nowadays. However, real world application for face recognition is still challenging. In this paper, we use Affine SIFT to detect affine invariant local descriptors for face recognition under large viewpoint change. Affine SIFT is an extension of SIFT algorithm. SIFT algorithm is scale and rotation invariant, which is powerful for small viewpoint changes in face recognition, but it fails when large viewpoint change exists. In our scheme, Affine SIFT is used for both gallery face and probe face, which generates a series of different viewpoints using affine transformation. Therefore, Affine SIFT allows viewpoint difference between gallery face and probe face. Experiment results show our framework achieves better recognition accuracy than SIFT algorithm on FERET database.

Viewpoint Unconstrained Face Recognition Based on Affine Local Descriptors and Probabilistic Similarity

  • Gao, Yongbin;Lee, Hyo Jong
    • Journal of Information Processing Systems
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    • 제11권4호
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    • pp.643-654
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    • 2015
  • Face recognition under controlled settings, such as limited viewpoint and illumination change, can achieve good performance nowadays. However, real world application for face recognition is still challenging. In this paper, we propose using the combination of Affine Scale Invariant Feature Transform (SIFT) and Probabilistic Similarity for face recognition under a large viewpoint change. Affine SIFT is an extension of SIFT algorithm to detect affine invariant local descriptors. Affine SIFT generates a series of different viewpoints using affine transformation. In this way, it allows for a viewpoint difference between the gallery face and probe face. However, the human face is not planar as it contains significant 3D depth. Affine SIFT does not work well for significant change in pose. To complement this, we combined it with probabilistic similarity, which gets the log likelihood between the probe and gallery face based on sum of squared difference (SSD) distribution in an offline learning process. Our experiment results show that our framework achieves impressive better recognition accuracy than other algorithms compared on the FERET database.

시점 변화에 강인한 특징점 정합 기법 (Feature Matching Algorithm Robust To Viewpoint Change)

  • 정현조;유지상
    • 한국통신학회논문지
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    • 제40권12호
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    • pp.2363-2371
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    • 2015
  • 본 논문에서는 FAST(Features from Accelerated Segment Test) 특징점 검출기와 SIFT(Scale Invariant Feature Transform) 특징점 서술자(descriptor)를 사용하여 시점 변화에 강인한 특징점 정합 기법을 제안한다. 기존의 FAST 기법은 영상의 에지 부분을 따라서 불필요하게 특징점을 많이 추출하게 되는데 이러한 단점을 주곡률(principal curvatures)을 적용하여 개선한다. 추출된 특징점을 SIFT 서술자를 통해 기술하고 시점이 다른 두 영상으부터 구해진 정합쌍에 RANSAC(RANdom SAmple Consensus) 기법을 통하여 호모그래피(homography)를 계산한다. 시점 변화에 강인한 특징점 정합을 위해서 기준 영상의 특징점들을 호모그래피 변환을 통해 변경된 좌표와 시점이 다른 영상의 특징점 좌표간의 유클리디언(Euclidean) 거리를 통해 정합쌍을 분류한다. 같은 물체나 장소에 대해 시점이 변화된 여러 영상에 대한 실험을 통해서 제안하는 정합 기법이 적은 계산량으로 기존의 특징점 정합 기법보다 우수한 성능을 보여주는 것을 확인하였다.

대학생 주거관의 시계열적 비교 (Comparison on the Time series of Housing Viewpoint of University Student)

  • 안옥희;강혜경;조영미
    • 한국주거학회:학술대회논문집
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    • 한국주거학회 2009년 춘계학술발표대회 논문집
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    • pp.243-246
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    • 2009
  • Housing distribution rate in our country has been continuously increased with economic growth, but residential plans satisfying the demands of residents are still not perfect yet. The demands of residents can be predicted by analyzing the housing viewpoint of residents. And also, the housing viewpoint can change according to various environmental changes, so it's important for us to understand the trend of change. Therefore, the housing viewpoints of university students who will be subjective residents of houses in future were analyzed by observing change due to trend of time. Target for this study is female university students in 20s. A portion of previously presented material (Korean Home Economics Association 37,1, 67-78) was used as data for 1998 and a questionnaire with 171 female university students was conducted on December 2008 for data for 2008. The following result was drawn from examination of change in the housing viewpoint due to trend of time by comparing the housing viewpoint of university students between 1998 and 2008. First, importance of was decreased and importance of was increased in functions of residence. Second, Most students thought and regardless of the time passage as their opinions on housing. And also, most students considered a living room as the most important space inside of a house regardless of the time passage and the ratio of considering a living room as the most important space was more increased.

경관 특성 파악에 있어서의 시퀀스적 시점장 선정과 전방위 화상정보의 유효성 검증에 관한 연구 (A Study of Selecting Sequential Viewpoint and Examining the Effectiveness of Omni-directional Angle Image Information in Grasping the Characteristics of Landscape)

  • 김홍만;이인희
    • KIEAE Journal
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    • 제9권2호
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    • pp.81-90
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    • 2009
  • Relating to grasping sequential landscape characteristics in consideration of the behavioral characteristics of the subject experiencing visual perception, this study was made on the subject of main walking line section for visitors of three treasures of Buddhist temples. Especially, as a method of obtaining data for grasping sequential visual perception landscape, the researcher employed [momentum sequential viewpoint setup] according to [the interval of pointers arbitrarily] and fisheye-lens-camera photography using the obtained omni-directional angle visual perception information. As a result, in terms of viewpoint selection, factors like approach road form, change in circulation axis, change in the ground surface level, appearance of objects, etc. were verified to make effect, and among these, approach road form and circulation axis change turned out to be the greatest influences. In addition, as a result of reviewing the effectiveness via the subjects, for the sake of qualitative evaluation of landscape components using the VR picture image obtained in the process of acquiring omni-directional angle visual perception information, a positive result over certain values was earned in terms of panoramic vision, scene reproduction, three-dimensional perspective, etc. This convinces us of the possibility to activate the qualitative evaluation of omni-directional angle picture information and the study of landscape through it henceforth.

3차원 건축모델정보의 표현변용방식에 관한 연구 (A Study on the Expression Transformation of Visual Information in 3D Architectural Models)

  • 박영호
    • 한국실내디자인학회논문집
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    • 제22권1호
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    • pp.105-114
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    • 2013
  • This study investigated the application and the change of various architectural models by analyzing expression viewpoint media, which were applied to the visual information of digitalized 3D contemporary architectural models. The purpose of this study was to specify how modern architects have changed 3D architectural models to conceptual, logical, and formational visual information in the process of design. This study discovered a framework of analyses by theoretically investigating a relationship between expression media and expression change in the process of visualizing architectural models. Using the framework of analyses, this study analyzed how the expression viewpoints of architectural model information have been changed and applied. The transformation media of the visual information of digitalized 3D architectural models can be classified into conceptual, analytical, and formational information: 1) Contemporary architects used author-centered subjective viewpoints to express architectural concepts, which were generated in the process of their design. They selected a perspective viewpoint and a bird's eye view in order to present their architectural concepts and to depict them with one architectural model by expanding the visual scope of conceptual information. 2) Contemporary architects adopted observer-centered objective bird's eye view expression media to effectively present their architectural information to building owners and viewers. They used transformal media, which integrate architectural information into 3D and change it to different scales, in order to express their architecture logically. 3) Contemporary architects delivered model information about the generation and change of forms by expressing the image of a project from an author-centered viewpoint, instead of objectively defining formational information. They explained the generation principle of architectural forms via transformal media which develop and rotate an architectural model.

Digital Watermarking Algorithm for Multiview Images Generated by Three-Dimensional Warping

  • Park, Scott;Kim, Bora;Kim, Dong-Wook;Seo, Youngho
    • Journal of information and communication convergence engineering
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    • 제13권1호
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    • pp.62-68
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    • 2015
  • In this paper, we propose a watermarking method for protecting the ownership of three-dimensional (3D) content generated from depth and texture images. After selecting the target areas to preserve the watermark by depth-image-based rendering, the reference viewpoint image is moved right and left in the depth map until the maximum viewpoint change is obtained and the overlapped region is generated for marking space. The region is divided into four subparts and scanned. After applying discrete cosine transform, the watermarks are inserted. To extract the watermark, the viewpoint can be changed by referring to the viewpoint image and the corresponding depth image initially, before returning to the original viewpoint. The watermark embedding and extracting algorithm are based on quantization. The watermarked image is attacked by the methods of JPEG compression, blurring, sharpening, and salt-pepper noise.

대학생 주거관의 시계열적 비교 (Comparison on the Time series of Housing Viewpoint of University Student)

중학교 3학년 '물질의 구성' 및 '물질 변화에서의 규칙성' 단원의 가설과 법칙에 대한 귀추적 관점이 과학 교사들의 사고에 미치는 영향 (The Effects of the Abduction Viewpoint on Science Teachers' Thoughts Related to Hypotheses and Laws in Ninth Grade 'Construction of Matter' and 'Rules of Matter Change' Chapters)

  • 김준예;백성혜
    • 한국과학교육학회지
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    • 제29권1호
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    • pp.10-21
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    • 2009
  • 이 연구에서는 중학교 3학년 '물질의 구성' 단원과 '물질 변화에서의 규칙성' 단원에서 다루는 가설과 법칙들을 과학 교사들이 어떻게 이해하고 있는지 알아보고, 귀추적 관점을 경험하였을 때 이들의 사고가 어떻게 변화하는지 알아보았다. 22명의 대학원 과정 화학 교사들을 대상으로 3주간 귀추법에 관련된 토론 수업을 진행하고, 수업에 참여한 교사들 중에 4명을 선발하여 사고의 변화를 면담과 보고서 등을 통해 조사하였다. 조사 결과, 교과서 내용 순서에 문제점을 인식하지 못하였던 교사 2명은 토론 수업 후에 법칙과 가설의 차이를 인식하는 사고로 변화하였다. 수업 전에 교과서의 내용 전개 순서에 문제가 있다고 생각하였던 교사 2명은 수업을 통해 귀추적 관점을 획득하였다. 또한 이들은 학생들의 지도 방식에 대한 새로운 견해와 귀추적 관점이 가지는 교육적 의미도 깨달았다.

전력 유도 장애 발생 시 통신 선로의 접지체 임피던스 크기가 유도 잡음 전압에 미치는 영향 분석 (Analysis on the Effects of the Induced Noise Voltage with the Impedance Changes of Telecommunication Line in the Power Inducting Situation)

  • 최문환;이상무;조평동
    • 한국정보통신설비학회:학술대회논문집
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    • 한국정보통신설비학회 2007년도 학술대회
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    • pp.227-230
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    • 2007
  • In this paper, we have analyzed the change characteristics of induced noise due to the impedance change of the ground in both ends of telecommunication line. As what affects the induced noise, there are power influence or longitudinal transverse voltages and its weighted filtered voltage. In the result of measurement, we can see the noise level change due to the change of the ground impedance, that is, as the ground impedance at either end of the telecommunication line become grower, the noise level is increased, and as the ground impedance at either end of the telecommunication line become smaller, the noise level is decreased. However, we can't define the relation between ground impedance size and PIF in these measurement results, so we will have to carry out the measurement more deeply and more practically with various conditions in environmental viewpoint and/or experimental viewpoint to establish the definition between ground impedance size and PIF.

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