• 제목/요약/키워드: Relative Disparity

검색결과 65건 처리시간 0.026초

광 JTC를 이용한 이동 물체의 스테레오 주시각 시차 추출 (Stereo Convergence Angle Disparity Extraction of the Moving Target using Optical JTC)

  • 이재수;김성호;김규태;김은수;박순영;이용범
    • 전자공학회논문지D
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    • 제35D권12호
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    • pp.99-107
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    • 1998
  • 스테레오 비젼 시스템은 사람의 눈 구조와 같이 좌,우 양방향에 위치한 두 대의 카메라로부터 영상이 입력되기 때문에 기존의 2차원 영상에 비해 보다 현실감 있는 입체 영상을 제공하는 특징을 갖고 있다. 그러나 스테레오 비젼 시스템에서 좌,우 영상의 시점이 일치하지 않을 경우 발생하는 스테레오 시차로 인해 오랜 시간동안 작업하는 관측자에게 눈의 피로감을 주고 물체의 입체감을 느끼지 못하기 때문에 스테레오 시차를 0으로 유지시키는 것이 요구되고 있다. 따라서 본 논문에서는 스테레오 시차를 0으로 유지시키기 위한 새로운 접근방법으로 적응적 물체 추적이 가능한 광 JTC를 이용하여 좌,우 영상에 대한 상관 첨두치의 상대적 위치 변화를 측정하는 새로운 스테레오 시차추출 방법을 제시하고, 광학적 실험을 통해 배경 잡음에 강하고 주시각 시차의 실시간적 제어가 가능한 스테레오 비젼 시스템을 제시하였다.

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Effective Route Decision of an Automatic Moving Robot(AMR) using a 2D Spatial Map of the Stereo Camera System

  • Lee, Jae-Soo;Han, Kwang-Sik;Ko, Jung-Hwan
    • 조명전기설비학회논문지
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    • 제20권9호
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    • pp.45-53
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    • 2006
  • This paper proposes a method for an effective intelligent route decision for automatic moving robots(AMR) using a 2D spatial map of a stereo camera system. In this method, information about depth and disparity map are detected in the inputting images of a parallel stereo camera. The distance between the automatic moving robot and the obstacle is detected, and a 2D spatial map is obtained from the location coordinates. Then the relative distances between the obstacle and other objects are deduced. The robot move automatically by effective and intelligent route decision using the obtained 2D spatial map. From experiments on robot driving with 240 frames of stereo images, it was found that the error ratio of the calculated distance to the measured distance between objects was very low, 1.52[%] on average.

Smart AGV system using the 2D spatial map

  • Ko, Junghwan;Lee, Jong-Yong
    • International Journal of Internet, Broadcasting and Communication
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    • 제8권4호
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    • pp.54-57
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    • 2016
  • In this paper, the method for an effective and intelligent route decision of the automatic ground vehicle (AGV) using a 2D spatial map of the stereo camera system is proposed. The depth information and disparity map are detected in the inputting images of a parallel stereo camera. The distance between the automatic moving robot and the obstacle detected and the 2D spatial map obtained from the location coordinates, and then the relative distance between the obstacle and the other objects obtained from them. The AGV moves automatically by effective and intelligent route decision using the obtained 2D spatial map. From some experiments on robot driving with 480 frames of the stereo images, it is analyzed that error ratio between the calculated and measured values of the distance between the objects is found to be very low value of 1.57% on average, respectably.

Stereoscopic Millimeter-wave Image Processing for Depth Information

  • Park, Min-Chul;Son, Jung-Young
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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    • pp.1022-1024
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    • 2009
  • Stereoscopic Images provide depth information with the relative distances between the objects in the images. There are many different ways to extract disparity maps from the visible spectral images. For the infrared spectral range, the same approach cannot be utilized for the innate low resolution and colorless features because typical methods require corresponding features between the images. The authors suggest a new approach that makes use of image segmentation to obtain depth information for stereoscopic millimeter-wave images. For image segmentation a selective visual attention model based on the theory of a feature-integration of attention is used. Experimental results show the proposed method provides reasonable depth information for object shape recognition and display.

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자극과 배경의 대비, 배경 텍스쳐 밀도, 자극의 화면 시차가 크로스톡 지각에 미치는 영향 (The Effects of Stimulus-background Contrast, Background Texture Density and Screen Disparity of Stimulus on Crosstalk Perception)

  • 박종진;이형철;김신우
    • 방송공학회논문지
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    • 제18권2호
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    • pp.225-236
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    • 2013
  • 3D 영상을 시청하면서 느끼는 고유한 피로를 입체 시각 피로라고 부른다. 이 현상을 유발시키는 주된 요인으로 꼽히는 것은 화면시차, 상 흐림, 크로스톡 (crosstalk)의 세 가지 요인으로 알려져 있다. 이 중 화면 시차와 상 흐림은 영상 콘텐츠에 의하여 결정되며, 사용하는 디스플레이 종류에 관계없이 직접 조작할 수 있다. 그러나 크로스톡 요인은 다른 요인과는 다르게 3D 디스플레이의 물리적인 특성에 의하여 결정되는 요인이며 따라서 손쉽게 감소시키거나 제거하는 것이 불가능하다. 그러나 크로스톡이 입체 시각 피로에 미치는 영향은 자극 특성에 의하여 달라지며, 이러한 자극 특성은 조작 가능하다. 따라서 크로스톡이 입체 시각 피로에 미치는 영향을 확인하려면 크로스톡 지각에 영향을 미치는 자극 특성의 효과를 확인하여야 한다. 이런 목적을 달성하기 위하여 상대적 깊이 판단 과제를 사용하여 자극 특성 (자극과 배경의 대비, 배경 텍스쳐 밀도, 자극의 화면 시차)이 크로스톡 지각에 미치는 영향을 확인하였다. 그 결과 영상에 배경이 존재하고 자극의 화면시차가 적을 때 지각되는 크로스톡이 감소함을 시사하는 결과를 얻었다.

가려짐 영역 검출 및 스테레오 영상 내의 특징들을 이용한 다시점 영상 생성 (Multi-view Image Generation from Stereoscopic Image Features and the Occlusion Region Extraction)

  • 이왕로;고민수;엄기문;정원식;허남호;유지상
    • 방송공학회논문지
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    • 제17권5호
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    • pp.838-850
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    • 2012
  • 본 논문에서는 스테레오 영상에서 얻은 다양한 특징들을 이용하여 다시점 영상을 생성하는 방법을 제안한다. 제안된 기법에서는 먼저 주어진 스테레오 영상에서 명암변화 주목도 지도(intensity gradient saliency map)를 생성한다. 다음으로 좌우 영상 간에 블럭 단위의 움직임을 나타내는 광류(optical flow)를 계산하고 scale-invariant feature transform(SIFT) 기법을 통해 사물의 크기와 회전에 변하지 않는 영상의 특징 점을 구하여 이 특징점 간의 변이를 구한 다음, 이 두 변이 정보들을 결합하여 변이 주목도 지도(disparity saliency map)를 생성 한다. 생성된 변이 주목도 지도는 가려짐 영역 검출을 통해 오류 변이가 제거된다. 세 번째로 영상 워핑시에 직선의 왜곡을 최소화하기 위해 직선 세그먼트를 얻는다. 마지막으로 다시점 영상은 이렇게 추출된 영상 특징들을 제한 조건으로 사용하여 그리드 메쉬(grid-mesh) 기반 영상 워핑(warping) 기법에 의해 생성된다. 실험 결과를 통해 제안한 기법으로 생성된 다시점 영상의 화질이 기존 DIBR 기법보다 우수한 것을 확인할 수 있었다.

Measuring Socioeconomic Disparities in Cancer Incidence in Tehran, 2008

  • Rohani-Rasaf, Marzieh;Moradi-Lakeh, Maziar;Ramezani, Rashid;Asadi-Lari, Mohsen
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권6호
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    • pp.2955-2960
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    • 2012
  • Background: Health disparities exist among and within countries, while developing and low income countries suffer more. The aim of this study was to quantify cancer disparities with regard to socioeconomic position (SEP) in 22 districts of Tehran, Iran. Method: According to the national cancer registry, 7599 new cancer cases were recorded within 22 districts of Tehran in 2008. Based on combined data from census and a population-based health equity study (Urban HEART), socioeconomic position (SEP) was calculated for each district. Index of disparity, absolute and relative concentration indices (ACI & RCI) were used for measuring disparities in cancer incidence. Results: The overall cancer age standardised rate (ASR) was 117.2 per 100,000 individuals (120.4 for men and 113.5 for women). Maximum ASR in both genders was seen in districts 6, 3, 1 and 2. Breast, colorectal, stomach, skin and prostate were the most common cancers. Districts with higher SEP had higher ASR (r=0.9, p<0.001). Positive ACI and RCI indicated that cancer cases accumulated in districts with high SEP. Female disparity was greater than for men in all measures. Breast, colorectal, prostate and bladder ASR ascended across SEP groups. Negative ACI and RCI in cervical and skin cancers in women indicate their aggregation in lower SEP groups. Breast cancer had the highest absolute disparities measure. Conclusion: This report provides an appropriate guide and new evidence on disparities across geographical, demographic and particular SEP groups. Higher ASR in specific districts warrants further research to investigate the background predisposing factors.

Penalizing the Negative Exponential Disparity in Discrete Models

  • Sahadeb Sarkar;Song, Kijoung-Song;Jeong, Dong-Bin
    • Communications for Statistical Applications and Methods
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    • 제5권2호
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    • pp.517-529
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    • 1998
  • When the sample size is small the robust minimum Hellinger distance (HD) estimator can have substantially poor relative efficiency at the true model. Similarly, approximating the exact null distributions of the ordinary Hellinger distance tests with the limiting chi-square distributions can be quite inappropriate in small samples. To overcome these problems Harris and Basu (1994) and Basu et at. (1996) recommended using a modified HD called penalized Hellinger distance (PHD). Lindsay (1994) and Basu et al. (1997) showed that another density based distance, namely the negative exponential disparity (NED), is a major competitor to the Hellinger distance in producing an asymptotically fully efficient and robust estimator. In this paper we investigate the small sample performance of the estimates and tests based on the NED and penalized NED (PNED). Our results indicate that, in the settings considered here, the NED, unlike the HD, produces estimators that perform very well in small samples and penalizing the NED does not help. However, in testing of hypotheses, the deviance test based on a PNED appears to achieve the best small-sample level compared to tests based on the NED, HD and PHD.

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알렉산더 맥퀸(Alexander Mcqueen) 작품의 그로테스크적 특성 (The Grotesque in the Work of Alexander McQueen)

  • 김선영
    • 복식
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    • 제58권8호
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    • pp.106-119
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    • 2008
  • This study explores grotesque characteristics that were raised as the Aesthetics of the Ugly and how it was featured in Alexander McQueen's arts. In a methodological approach, the study attempted the analysis of historical literature that was published both nationally and internationally, along with justifiable investigation using fashion/collection magazines such as Vogue, Gap and Internet search. The scope of this study ranges from 1996's Haute Couture and Pret-a-porter collection pieces modern, to date The results of this study are summarized as follows: The first grotesque characteristic present throughout Alexander Mcqueen's arts is that it featured horrifying images or evil motives with pointy heads or horns, dark colored dresses, silver accessories, Dracula, witches, skulls, soldiers of evil, death and sickness. Second, aversion was realistically portrayed by frightening objects, extreme intimacy and motives that signify death and closely relative to cruelty to human bodies. It also became visible with physical destruction of the bodies and dissecting of internal organs, etc. Thirdly, its expression of humor is out of common sense with distorted human bodies by intentionally overemphasizing certain portion of the clothes or body parts. It also featured strangely deformed bodies by ignoring the typical shapes of clothes, vague definition of gender and using of unusual objects. Forth, half-man and half-beast images are portrayed using various types of bird species or animals to Identify disparity. It further defined this image in the form of non-human cyborg by incorporating technology.

웨이브릿 변환을 이용한 계층적 스테레오 정합 (A Hierarchical Stereo Matching Algorithm Using Wavelet Representation)

  • 김영석;이준재;하영호
    • 전자공학회논문지B
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    • 제31B권8호
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    • pp.74-86
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    • 1994
  • In this paper a hierarchical stereo matching algorithm to obtain the disparity in wavelet transformed domain by using locally adaptive window and weights is proposed. The pyramidal structure obtained by wavelet transform is used to solve the loss of information which the conventional Gaussian or Laplacian pyramid have. The wavelet transformed images are decomposed into the blurred image the horizontal edges the vertical edges and the diagonal edges. The similarity between each wavelet channel of left and right image determines the relative importance of each primitive and make the algorithm perform the area-based and feature-based matching adaptively. The wavelet transform can extract the features that have the dense resolution as well as can avoid the duplication or loss of information. Meanwhile the variable window that needs to obtain precise and stable estimation of correspondense is decided adaptively from the disparities estimated in coarse resolution and LL(low-low) channel of wavelet transformed stereo image. Also a new relaxation algorithm that can reduce the false match without the blurring of the disparity edge is proposed. The experimental results for various images show that the proposed algorithm has good perfpormance even if the images used in experiments have the unfavorable conditions.

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