• Proceedings of the KIEE Conference
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• 2002.07d
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• pp.2528-2530
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• 2002

본 연구에서는 캘리브레이션 박스와 같은 사전에 약속된 물체를 사용하지 않고 일반적인 환경(unstructured environment)의 컬러 스테레오 영상으로부터 특징점을 찾고, 특징점 사이의 대응관계를 사용자 개입 없이 파악하는 방법에 대해 소개한다. 또한 찾은 대응관계를 이용해 스테레오 카메라 사이의 에피폴라 기하학(epipolar geometry) 관계를 계산하여 셀프 캘리브레이션에 이용한다. 이와 유사한 연구는 많이 진행되어 왔으나 대부분의 연구가 흑백 영상에서 진행되어 왔다. 본 연구에서는 컬러 이미지의 속성을 이용해 흑백 영상을 이용할 때보다 외부 환경의 변화에 강인하며, 정밀한 대응 관계를 찾을 수 있음을 실험을 통해 보인다.

• Proceedings of the IEEK Conference
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• 2001.06d
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• pp.135-138
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• 2001

Many researchers have developed the techniques of an efficient 3-D sound system based on the psycho-acoustics of spatial hearing with multimedia or virtual reality In this paper, we propose an idea for the improved 3-D sound system using conventional stereo headphones to obtain a better sound diffusion from the mono-sound recorded at an anechoic chamber. We use the HRTF (Head Related Transfer Function) for the sound localization and the wavelet filter bank with time delay for the sound diffusion. We investigate the effects of the 3-B sound depending on the length of time delay at lowest frequency band. Also the correlation coefficient of the signals between the left channel and the right channel is measured to identify the sound diffusion.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.553-558
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• 2008

Advancement in information technology have enabled applying vision sensor to railway, such as CCTV. CCTV has been widely used in railway application, however the CCTV is a passive system that provide limited capability to maintain safety from boarding platform. The station employee should monitor continuously CCTV monitors. Therefore immediate recognition and response to the situation is difficultin emergency situation. Recently, urban transit operators are pursuing applying an unattended station operation system for their cost reduction. Therefore, an intelligent monitoring system is need for passenger's safety in railway. The paper proposes a vision based monitoring system and object detection algorithm for passenger's safety in railway platform. The proposed system automatically detects accident in platform and analyzes level of danger using image processing technology. The system uses stereo vision technology with multi-sensors for minimizing detection error in various railway platform conditions.

• Journal of Integrative Natural Science
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• v.5 no.2
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• pp.120-126
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• 2012

This paper describes the algorithm that lowers the dimension, maintains the gesture recognition and significantly reduces the eigenspace configuration time by combining the higher correlation feature information and Principle Component Analysis. Since the suggested method doesn't require a lot of computation than the method using existing geometric information or stereo image, the fact that it is very suitable for building the real-time system has been proved through the experiment. In addition, since the existing point to point method which is a simple distance calculation has many errors, in this paper to improve recognition rate the recognition error could be reduced by using several successive input images as a unit of recognition with K-Nearest Neighbor which is the improved Class to Class method.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1998.03a
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• pp.149-152
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• 1998

정보통신 기술이 급격히 발달함에 따라 영상처리 및 압축 기술에 대한 중요성이 대두되고 있다. 현재 정지 압축 영상 표준인 JPEG과 동영상 압축 표준인 MPEG에서는 통계적 특성에 기반한 DCT 방법을 이용하여 압축을 수행하고 있다. 최근에는 웨이브렛 변환을 이용한 영상신호 처리 및 압축에 관한 연구가 활발히 이루어지고 있는데, 이는 기존의 DCT 방법과는 달리 속도와 압축률이 뛰어나며 블록화 현상(Blocking Effect)이 발생하지 않기 때문이다. 또한 웨이브렛 자체가 함수이고 이러한 함수에 다른 스케일과 해상도를 적용하는것이므로, 영상을 확대하거나 축소하더라도 이미지에 손상을 주지 않고 복원할 수 있다. 스테레오 이미지는 사람의 시각에서 물체를 보는 것처럼, 카메라에서 같은 장면을 약간의 차이를 두어 찍은 것이다. 따라서 오른쪽과 왼쪽의 두 이미지로 나누어지게 되는데, 이 두 이미지 사이에서 공통 부분이 많다는 특징을 가지게 된다. 따라서 두 이미지의 공통 부분을 찾아 내고, 이를 이용하여 압축을 할 수 있다면 압축률을 높일 수 있다. 본 연구에서는 웨이브렛 변환을 이용하여 스테레오 이미지에서의 공통 부분을 찾고 영상을 효율 岵막\ulcorner 압축하는 방법에 대하여 연구한다.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.34S no.3
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• pp.74-83
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• 1997

In this paper, a new stereo matching algorithm is proposed which uses th econstrainted optimization technique and the matching measures between the segments extracted from zero-crossing edges. The initial matching measures and average disparities are calculated by the features of segments on the searching window of the left and right images. The matching measure is calculated by applying an exponential function using the differences of slope, overlapped length and intensity. The coherency constraint is that neighbouring image points corresponding to the same object should have nearly the same disparities. The matching measures are iteratively updated by applying the coherency constraint. Simulation results on various images show that the proposed algorithm more acculately extracts the segment disparity.

• Journal of International Society for Simulation Surgery
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• v.3 no.1
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• pp.16-21
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• 2016

Computed tomography (CT) can completely digitize the interior and the exterior of nearly any object without any destruction. Generally, the resolution for industrial CT is below a few microns. The industrial CT scanning, however, has a limitation because it requires long measuring and processing time. Whereas, 2D X-ray imaging is fast. In this paper, we propose a novel concept of 3D non-destructive inspection technique using the advantages of both micro-CT and dual X-ray images. After registering the master object’s CT data and the sample objects’ dual X-ray images, 3D non-destructive inspection is possible by analyzing the matching results. Calculation for the registration is accelerated by parallel computing using graphics processing unit (GPU).

• Proceedings of the Korea Information Processing Society Conference
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• 2001.10a
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• pp.739-742
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• 2001

영상처리 기법을 이용하여 움직이는 물체를 추적하는 시스템은 많은 분야에 응용될 수 있다. 기존의 물체 추적 시스템에서 사용한 방법들은 최적의 특성을 지니고 있지만, 많은 계산량을 요구하는 단점이 있다. 또한 단안에 의한 영상의 경우 물체의 다양한 변화에 대한 예측과 추적이 어렵다. 따라서 본 논문에서는 양안에 의해 얻어진 스테레오 영상에 전이(translation)와 회전(rotation)에서의 예측이 어려운 단점을 보완한 블록 정합 알고리즘을 적용함으로써 실시간 물체의 변화의 추적능력을 지니면서도 그 계산량을 줄일 수 있는 추적 방법에 대하여 기술한다. 또한 히스토그램의 계수 변화를 이용함으로써 블록 정합 알고리즘에서의 탐색영역을 제한하도록 하여 불필요한 처리시간을 절약하는 효율적인 물체추적 시스템을 제안한다.

• Proceedings of the KIEE Conference
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• 1993.07a
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• pp.414-417
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• 1993

The methods for stereo matching are divided into two techniques: area-based matching and feature-based matching. To find corresponding points by area-based method, it takes a lot of time because there are many points to be matched. Feature-based matching algorithm is often used because with this method it matches only some feature points so that the processing time is fast even though it requires interpolation after matching. In this paper, we propose the smart technique by which we makes features simpler than conventional methods to match an image pair by feature-based matching algorithm.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.508-509
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• 2007

For the safty driving of an automobile which is become individual requisites, a new Neural Network algorithm which recognized the load vehicles in real time is proposed. The proposed neural network technique is the real time computation method through the inter-node diffusion. The most reliable algorithm derived for real time recognition of vehicles, is a dynamic programming based algorithm based on sequence matching techniques that would process the data as it arrives and could therefore provide continuously updated neighbor information estimates.