• Journal of information and communication convergence engineering
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• 제13권3호
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• pp.197-204
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• 2015

In this paper, we present an algorithm for the detection of illegally parked vehicles based on a combination of some image processing algorithms. A digital camera is fixed in the illegal parking region to capture the video frames. An adaptive Gaussian mixture model (GMM) is used for background subtraction in a complex environment to identify the regions of moving objects in our test video. Stationary objects are detected by using the pixel-level features in time sequences. A stationary vehicle is detected by using the local features of the object, and thus, information about illegally parked vehicles is successfully obtained. An automatic alarm system can be utilized according to the different regulations of different illegal parking regions. The results of this study obtained using a test video sequence of a real-time traffic scene show that the proposed method is effective.

• 인지과학
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• 제18권2호
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• pp.113-138
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• 2007

풍경 그림을 사용하여 도식이 기억에 미치는 영향을 알아보았다. 실험 1에서는 즉시 검사를 실시하여 부호화할 때 도식이 기억에 미치는 영향을 알아보았고, 실험 2에서는 3일 지연 검사를 실시하여 파지기간 동안 도식이 기억에 미치는 영향을 알아보았다. 두 실험 모두에서 제시시간(250ms vs 1000ms)을 다르게 하고 목표 미끼를 생략하는 조건과 목표 미끼를 다른 물건으로 대체하는 조건으로 항목의 축어적 정보 부호화를 조작하였다. 특히 생략과 대체 조건을 비교하여 도식에 기반한 기대라는 하향정보 특정항목에 대한 상향정보가 기억에 미치는 효과를 알아보았다. 두 개의 실험에서 전형적인 항목에 대한 오기억은 지연검사에서도 별 변화가 없는데 반해 학습 항목에 대한 기억은 감소하였으며, 오기억은 생략조건에서 더 많이 보고되었으나, 비전형 항목에 대한 기억은 감소하였으며, 오기억은 생략조건에서 더 많이 보고되었으나, 비전형 항목에 대한 기억은 대체조건에서 더 많이 보고되었다. 이 결과는 도식에 기반한 오기억은 비교적 지속적이며, 도식에 의한 기대라는 하향 정보가 상향 정보와 충돌이 일어날 때에는 오기억이 감소한다는 사실을 보여 주었다.

• Journal of Mechanical Science and Technology
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• 제15권3호
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• pp.300-308
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• 2001

Tracking of moving objects within video streams is a complex and time-consuming process. Large number of moving objects increases the time for computation of tracking the moving objects. Because of large computations, there are real-time processing problems in tracking of moving objects. Also, the change of environment causes errors in estimation of tracking information. In this paper, we present a new method for tracking of moving objects using optical flow motion analysis. Optical flow represents an important family of visual information processing techniques in computer vision. Segmenting an optical flow field into coherent motion groups and estimating each underlying motion are very challenging tasks when the optical flow field is projected from a scene of several moving objects independently. The problem is further complicated if the optical flow data are noisy and partially incorrect. Optical flow estimation based on regulation method is an iterative method, which is very sensitive to the noisy data. So we used the Combinatorial Hough Transform (CHT) and Voting Accumulation for finding the optimal constraint lines. To decrease the operation time, we used logical operations. Optical flow vectors of moving objects are extracted, and the moving information of objects is computed from the extracted optical flow vectors. The simulation results on the noisy test images show that the proposed method finds better flow vectors and more correctly estimates the moving information of objects in the real time video streams.

• Journal of Electrical Engineering and information Science
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• 제1권2호
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• pp.77-86
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• 1996

In this paper we deal with the problem of recovering 3-D motion and structure from a time-varying 2-D velocity vector field. A great deal has been done on this topic, most of which has concentrated on finding necessary and sufficient conditions for there to be a unique 3-D solution corresponding to a given 2-D motion. While previous work provides useful theoretical insight, in most situations the known algorithms have turned out to be too sensitive to be of much practical use. It appears that any robust algorithm must improve the 3-D solutions over time. As a step toward such algorithm, we present a method for recovering 3-D motion and structure from a given time-varying 2-D velocity vector field. The surface of the object in the scene is assumed to be locally planar. It is also assumed that 3-D velocity vectors are piecewise constant over three consecutive frames (or two snapshots of flow field). Our formulation relates 3-D motion and object geometry with the optical flow vector as well as its spatial and temporal derivatives. The linearization parameters, or equivalently, the first-order flow approximation (in space and time) is sufficient to recover rigid body motion and local surface structure from the local instantaneous flow field. We also demonstrate, through a sensitivity analysis carried out for synthetic and natural motions in space, that 3-D motion can be recovered reliably.

• 한국컴퓨터정보학회논문지
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• 제18권4호
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• pp.13-18
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• 2013

디지털 카메라의 보급으로 카메라만 있으면 누구나 손쉽게 파노라마 사진을 찍을 수 있다. 파노라마 사진이란 카메라를 삼각대에 고정시킨 후, 일부분을 중첩시키면서 회전하여 얻어진 이미지를 수평으로 이동하여 이미지를 결합시키는 사진이다. 이때 수동으로 사진을 찍을 경우에는 각도가 틀어져 겹쳐지는 부분을 자연스럽게 정합하기 어렵다. 기존의 방법에서는 라벨링을 이용하여 객체를 비교한 후에 결합시키는 방법을 적용하였으나 시간이 많이 소요되고 각각의 이미지를 라벨링하는 과정에서 개체 간의 불일치가 발생하여 정확히 영상을 결합할 수 없는 경우가 발생한다. 따라서 본 논문에서는 처리 속도 개선을 위하여 전체 이미지의 1/3만 라벨링한 후에 객체 간을 비교하여 결함시킨다. 그리고 각도가 틀린 경우에는 특징점을 찾아내는 SURF 알고리즘을 적용하여 각각의 이미지에서 라벨링한 사각형의 4개의 포인터에 대해 1개의 중심점을 구하여 호모그래피를 이용하여 2개의 영상을 자연스럽게 정합한다. 본 논문에서 제안한 파노라마 영상 재구성 방법의 성능을 평가하기 위하여 다양한 이미지를 대상으로 실험한 결과, 기존의 방법보다 영상을 재구성하는데 효과적인 것을 확인하였다.

• 한국컴퓨터그래픽스학회논문지
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• 제20권1호
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• pp.13-19
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• 2014

본 논문에서는 현실감 있는 렌더링을 위하여 최근 널리 사용되고 있는 영상 기반 조명(image-based lighting)과정을 실시간으로 처리하기위한 기술을 다룬다. 기존의 영상을 광원으로 사용하는 실시간 렌더링 기법에서는 주로 난반사(diffuse reflection)와 거울 면 정반사(mirror-like specular reflection)을 다루는 반면, 본 논문에서는 기존에 컴퓨터 그래픽스 분야에서 널리 사용하던 퐁 반사 모델(Phong reflection model)을 실시간으로 렌더링 하기 위한 방법을 제안한다. 특히 새로운 방법론 보다는 기존의 방법들을 확장하여 게임이나 실시간 미리보기 등의 응용에서 전통적인 방법으로 제작된 표면 속성을 가지는 기하객체를 보다 사실적으로 렌더링하기 위한 실용적인 방법을 제안한다. 난반사의 경우에는 기존의 방법과 유사하게 전처리 과정에서 원본 광원 영상으로부터 난반사를 실시간으로 계산하기 위한 영상을 생성하는 방법을 사용한다. 정반사의 경우에도 유사하게 전처리 과정에서 광택도(shininess)에 따른 반사 맵을 미리 생성하고 이를 물체의 광택도(shininess)에 따라서 보간하는 방법을 사용한다. 이와 같은 방법으로 실시간에 비교적 매우 적은 양의 계산과 적은 텍스처 참조를 통하여 영상 기반 조명을 근사할 수 있다.

• Journal of Information Technology Applications and Management
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• 제29권1호
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• pp.47-57
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• 2022

The purpose of this study is to analyze the current status of augmented reality picture books, which have been steadily developed since 2010, as a genre of electronic picture books, and to reveal how children's immersion in augmented reality picture books differs from paper picture books. To this end, 30 augmented reality picture books on the market were analyzed according to genre, life theme, implementation method, and augmented reality scene ratio. As a result of the study, it was found that the genre of picture books was in the order of information fairy tales, daily fairy tales, and historical fairy tales, and there were no traditional or fantasy fairy tales. Animals and plants accounted for about half of the life topics, and in some cases, there were only a few or no other life topics. In the augmented reality implementation scene, it consisted of only one page in the early days, but all pages are now possible to implement augmented reality due to technology development, production cost reduction, and improved hardware performance of smartphones. It was found that the augmented reality implementation method used CD-ROM in the early days, but gradually became possible to implement using only mobile phones and tablets that were easy for readers to access. In addition, after presenting four picture books to eight 5-year-old infants, the immersion time was measured and the immersion behavior was observed. As a result, augmented reality picture books showed higher immersion[immersion time, immersion behavior] than paper picture books, but compared by literature genre, life fairy tales were higher in paper picture books and natural fairy tales in augmented reality picture books. It was higher when presenting augmented reality picture books after presenting paper picture books according to the order of presentation of picture book types. The results of this study suggest that more diverse life topics and augmented reality picture books in the genre of children's literature should be developed to increase the utilization of augmented reality picture books. In addition, considering that there are differences in immersion between types, literary genres, and reading experience [presentation order], it is expected to increase the educational effect by using picture books complementarily.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.691-694
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• 2006

So far, we have done much research improving quality of LCD TV. Recently, we have developed 26" WXGA LCD TV by advance fringe field switching (AFFS) technology with smooth and every scene realistic in color image that obtained from the amazing authentic color delivery, optical characteristic and fast response time. Our upgrade device has shown the brightness over 600nits (Color shift <0.015 and Transmittance ratio > 5.5%), gray to gray response time under 6ms, contrast ratio over 1200:1 and viewing angle over 178/178, respectively. And also, motion artifacts improved by fast response of LC with low viscosity, cell gap and dielectric constant.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2002년도 ICCAS
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• pp.100.3-100
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• 2002

This paper presents the method for detection and tracking of multiple humans robustly in mobile platform. The perception of human is performed in real time through the processing of images acquired from a moving stereo vision system. We performed multi-cue integration such as human shape, skin color and depth information to detect and track each human in moving background scene. Human shape is measured by edge-based template matching on distance transformed image. Improving robustness for human detection, we apply the human face skin color in HSV color space. And we could increase the accuracy and the robustness in both detection and tracking by applying random sampling stochastic estimati...

• 스마트미디어저널
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• 제1권3호
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• pp.48-55
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• 2012

In general, background subtraction based methods are used to detect the moving objects in visual tracking applications. In this paper we employed background subtraction based scheme to detect the temporarily stationary objects. We proposed two schemes for stationary object detection and we compare those in terms of detection performance and computational complexity. In the first approach we used single background and in the second approach we used dual backgrounds, generated with different learning rates, in order to detect temporarily stopped object. Finally, we used normalized cross correlation (NCC) based image comparison to monitor and track the detected stationary object in a video scene. The proposed method is robust with partial occlusion, short time fully occlusion and illumination changes, as well as it can operate in real time.