• 정보기술과데이타베이스저널
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• 제6권2호
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• pp.19-28
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• 1999

Digital image and video libraries require new algorithms for the automated extraction and indexing of salient image features. Eigen values of an image provide one important cue for the discrimination of image content. In this paper we propose a new approach for automated content extraction that allows efficient database searching using eigen values. The algorithm automatically extracts eigen values from the image matrix represented by the covariance matrix for the image. We demonstrate that the eigen values representing shape information and the skewness of its distribution representing complexity provide good performance in image query response time while providing effective discriminability. We present the eigen value extraction and indexing techniques. We test the proposed algorithm of searching by eigen value and its skewness on a database of 100 images.

• ETRI Journal
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• 제37권5호
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• pp.1023-1031
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• 2015

In infrared (IR) images, near targets have a transient distribution at the boundary region, as opposed to a steady one at the inner region. Based on this fact, this paper proposes a novel IR target extraction method that uses both a weighted information entropy (WIE) and an adaptive opening filter to extract near finely shaped targets in IR images. Firstly, the boundary region of a target is detected using a local variance WIE of an original image. Next, a coarse target region is estimated via a labeling process used on the boundary region of the target. From the estimated coarse target region, a fine target shape is extracted by means of an opening filter having an adaptive structure element. The size of the structure element is decided in accordance with the width information of the target boundary and mean WIE values of windows of varying size. Our experimental results show that the proposed method obtains a better extraction performance than existing algorithms.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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• pp.238-242
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• 2007

Today's commercial high resolution satellite imagery such as that provided by IKONOS and QuickBird, offers the potential to extract useful spatial information for geographical database construction and GIS applications. Digital maps supply the most generally used GIS data probiding topography, road, and building information. Currently, the building information provided by digital maps is incompletely constructed for GIS applications due to planar position error and warped shape. We focus on extracting of the accurate building information including position, shape, and height to update the building information of the digital maps and GIS database. In this paper, we propose a new method of 3D building information extraction with a single high resolution satellite image and digital map. Co-registration between the QuickBird image and the 1:1,000 digital maps was carried out automatically using the RPC adjustment model and the building layer of the digital map was projected onto the image. The building roof boundaries were detected using the building layer from the digital map based on the satellite azimuth. The building shape could be modified using a snake algorithm. Then we measured the building height and traced the building bottom automatically using triangular vector structure (TVS) hypothesis. In order to evaluate the proposed method, we estimated accuracy of the extracted building information using LiDAR DSM.

• 한국정보통신학회논문지
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• 제18권3호
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• pp.670-678
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• 2014

본 논문에서는 방사선 영상에서의 영역에 대한 임의의 조합 및 푸리에 기술자를 이용한 물체 검색 방법을 제안한다. 영상에서의 물체 인식에 있어 폐색 현상은 가장 문제가 된다. 하지만 방사선 영상에서는 다른 객체에 의해 폐색되는 현상이 발생하지 않는 이점이 있다. 이는 방사선 영상은 객체를 투과하는 방사선 양을 표현하기 때문이다. 이러한 방사선 영상의 특성을 고려할 때 객체를 찾는 과정에서 모양 기반의 기술자를 사용하는 것은 매우 효과적일 수 있다. 제안된 객체 추출 방법은, 영역 분할, 분할된 영역의 모든 경우의 수에 대한 조합 수행, 조합된 영역과 모델 영상과의 비교, 이렇게 세 단계로 구성된다. 또한 모델과의 비교 이전에 예상 가능한 불필요한 연산을 조합 과정에서 제거하였다. 모델과의 비교에 있어 회전과 이동에 강인한 푸리에 기술자를 이용하였다. 또한 크기 변화에 강인하기 위해 정규화 과정을 적용하였다. 최종적으로 제안된 방법을 통한 객체 추출 성능을 실험을 통해 확인하였다.

• 대한건축학회연합논문집
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• 제20권6호
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• pp.81-87
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• 2018

In this paper, in order to maximize the input process efficiency of the building energy simulation field, the authors developed the automatic extraction module of spatial information based BIM geometry information. Existing research or software extracts geometry information based on object information, but it can not be used in the field of energy simulation because it is inconsistent with the geometry information of the object constituting the thermal zone of the actual building model. Especially, IFC-based geometry information extraction module is needed to link with other architectural fields from the viewpoint of reuse of building information. The study method is as follows. (1) Grasp the category and attribute information to be extracted for energy simulation and Analyze the IFC structure based on spatial information (2) Design the algorithm for extracting and reprocessing information for energy simulation from IFC file (use programming language Phython) (3) Develop the module that generates a geometry information database based on spatial information using reprocessed information (4) Verify the accuracy of the development module. In this paper, the reprocessed information can be directly used for energy simulation and it can be widely used regardless of the kind of energy simulation software because it is provided in database format. Therefore, it is expected that the energy simulation process efficiency in actual practice can be maximized.

• 대한기계학회논문집A
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• 제21권8호
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• pp.1241-1249
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• 1997

The problem of structural topology optimization can be relaxed and converted into the optimal density distribution problem. The optimal density distribution must be post-processed to get the real shape of the structure. The extracted shape can then be used for the next process, which is usually shape optmization based on the boundary movement method. In the practical point of view, it is very important to get the optimal density distribution from which the corresponding shape can easily be extracted. Among many other factors, the presence of checker-board patterns is a powerful barrier for the shape extraction job. The nature of checker-board patterns seems to be a numerical locking. In this paper, an efficient algorithm is presented to suppress the checker-board patterns. At each iteration, density is re-distributed after it is updated according to the optimization rule. The algorithm also results in the optimal density distribution whose corresponding shape has smooth boundary. Some examples are presented to show the performance of the density re-distribution algorithm. Checker-board patterns are successfully suppressed and the resulting shapes are considered very satisfactory.

• 한국멀티미디어학회논문지
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• 제23권8호
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• pp.953-964
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• 2020

Ever since media contents took over the world, the importance of typography has increased, and the influence of fonts has be n recognized. Nevertheless, the current Hangul font system is very poor and is provided passively, so it is practically impossible to understand and utilize all the shape characteristics of more than six thousand Hangul fonts. In this paper, the characteristics of Hangul font shapes were selected based on the Hangul structure of similar fonts. The stroke element detection training was performed by fine tuning Faster R-CNN Inception v2, one of the deep learning object detection models. We also propose a system that automatically extracts the stroke element characteristics from characters by introducing an automatic extraction algorithm. In comparison to the previous research which showed poor accuracy while using SVM(Support Vector Machine) and Sliding Window Algorithm, the proposed system in this paper has shown the result of 10 % accuracy to properly detect and extract stroke elements from various fonts. In conclusion, if the stroke element characteristics based on the Hangul structural information extracted through the system are used for similar classification, problems such as copyright will be solved in an era when typography's competitiveness becomes stronger, and an automated process will be provided to users for more convenience.

• 대한원격탐사학회지
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• 제24권3호
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• pp.235-243
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• 2008

Object tracking is a common vision task to detect and trace objects between consecutive frames. It is also important for a variety of applications such as surveillance, video based traffic monitoring system, and so on. An efficient moving vehicle clustering and tracking algorithm suitable for traffic monitoring system is proposed in this paper. First, automatic background extraction method is used to get a reliable background as a reference. The moving blob(object) is then separated from the background by mean shift method. Second, the scale invariant feature based method extracts the salient features from the clustered foreground blob. It is robust to change the illumination, scale, and affine shape. The simulation results on various road situations demonstrate good performance achieved by proposed method.

• 한국멀티미디어학회논문지
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• 제14권1호
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• pp.1-14
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• 2011

영상의 유통이 활발해 지면서 증가하는 데이터베이스를 효율적으로 관리하기 위한 다양한 요구들이 생겨났다. 내용 기반 기술은 이런 요구들을 충족시켜 줄 기술 중 하나이다. 내용 기반 기술에서는 다양한 특징 방법을 이용해 영상을 표현할 수 있지만, 그 중 전역 특정 방법은 추출된 특정 벡터가 규격화 되어 빠른 정합 속도를 확보할 수 있다는 장점이 있다. 전역 특정 방법은 크게 공간적 특성을 이용한 방법과 통계적 특성을 이용한 방법으로 분류할 수 있고, 각각은 다시 컬러 성분을 이용한 방법과 밝기 성분을 이용한 방법으로 분류된다. 본 논문에서는 이와 같은 분류 방법에 따라 다양한 전역 특정 방법들을 살펴보고, 정확성 실험, 재현율-정확도 그래프, ANMRR, 특징 벡터 크기-정합시간 등을 이용해 개별 전역 특정들의 성능을 비교하였다. 실험 결과 공간적 특성을 이용한 전역 특징은 비기하학적 변형에서 특히 뛰어난 성능을 보였으며, 컬러 성분과 히스토그램을 이용한 전역 특정 방법이 가장 좋은 성능을 보였다.

• 한국멀티미디어학회논문지
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• 제5권4호
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• pp.415-425
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• 2002

본 논문에서는 웨이브릿 변환 영역에서 추출된 특징을 기반으로 한 내용기반 영상검색 방법에 관해 연구하였다. 기존의 웨이브릿 기반의 방법에서의 문제점인 특징벡터의 크기를 줄이기 위해 웨이브릿 계수의 영역별 에너지 값을 이용하였으며, 대상물의 이동, 회전, 크기 변화에 영향을 받지 않는 모멘트 특성을 이용한 검색방법을 제안하였다. 본 방법은 특징벡터의 크기를 줄이고, 기존의 특징벡터와 비교해서 검색시간을 단축하면서 분류검색의 효율성을 향상시켰다. 영역기반 영상검색 기능을 제공하기 위해 영상분할 방법에 대해 연구하였으며, 불규칙한 광원에 의한 영향을 최소화할 수 있는 영상분할 방법을 제안하였다 영상분할은 영역병합을 이용하였고, 병합후보영역은 웨이브릿 변환의 고주파 대역 에너지 값을 이용하여 선정하였다 분할된 영역정보를 이용하여 칼라와 질감, 모양 특징벡터를 구성하여 영역기반 영상검색을 수행하였다.