• 제목/요약/키워드: watershed algorithm

검색결과 244건 처리시간 0.022초

에지 정보를 이용한 watershed 영역 추출에 관한 연구 (A Study On Watershed Region Extraction Based On Edge Information)

  • 이원효;조상현;설경호;주동현;김두영
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2003년도 신호처리소사이어티 추계학술대회 논문집
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    • pp.449-452
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    • 2003
  • This paper propose a extracting method of the region for image using segmentation and edge information. First propose algorithm extract information using canny edge detector and the image was divided by watershed segmentation. And it extract the mage with edge information by merging region. Finally we compare the proposed method with levelset method. In the result proposed method not only extract the image with accurate region but also reduce operation time.

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Background Subtraction for Moving Cameras based on trajectory-controlled segmentation and Label Inference

  • Yin, Xiaoqing;Wang, Bin;Li, Weili;Liu, Yu;Zhang, Maojun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제9권10호
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    • pp.4092-4107
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    • 2015
  • We propose a background subtraction method for moving cameras based on trajectory classification, image segmentation and label inference. In the trajectory classification process, PCA-based outlier detection strategy is used to remove the outliers in the foreground trajectories. Combining optical flow trajectory with watershed algorithm, we propose a trajectory-controlled watershed segmentation algorithm which effectively improves the edge-preserving performance and prevents the over-smooth problem. Finally, label inference based on Markov Random field is conducted for labeling the unlabeled pixels. Experimental results on the motionseg database demonstrate the promising performance of the proposed approach compared with other competing methods.

TOPMODEL과 Muskingum 기법을 이용한 안성천유역의 홍수유출분석 (Flood Runoff Analysis on the Anseong-cheon watershed using TOPMODEL and Muskingum method.)

  • 권형중;김성준
    • 한국농공학회:학술대회논문집
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    • 한국농공학회 2002년도 학술발표회 발표논문집
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    • pp.289-292
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    • 2002
  • In this study, a topography based hydrologic model (TOPMODEL) was tested on the Anseong-cheon watershed. Pit in watershed was removed by liner trend surface interpolator. The DTM Analysis program is used to derived a distribution of ln($a/tan{\beta}$) values from DEM (Digital Elevation Model) using the MDF (Multiple Direction Flow) algorithm of Quinn et al (1995). Current TOPMODEL program limits are number of time step, ln($a/tan{\beta}$) increment, delay histogram ordinate and size of subcatchment pixel maps. Therefore, TOPMODEL is not suitable for application of large watershed. Muskingum method and watershed division enhance grid pixel resolution for rainfall-runoff simulation accuracy.

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개선된Watershed영상분할방법 (The Watershed Image Segmentation Iteration Method)

  • 권기홍
    • 한국컴퓨터산업학회논문지
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    • 제4권12호
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    • pp.923-928
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    • 2003
  • 잡음의 혼입, 추가적인 데이터의 삽입에 의해 많은 catchments basins 이 보다 더 부분 분할되어 local minima 가 증가하는 경우 훼손된 Watershed 영상은 관련된 객체 윤곽들이 소실되는 over segmentation 이 발생한다 제안된 Watershed 영상 분할 알고리즘은 반복적으로 유사 gray level 분포를 지니는 인접 영역을 병합, 영상 복원하여 기존의 알고리즘보다 우수한 효과를 나타낼 것으로 기대된다.

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Watershed Segmentation of High-Resolution Remotely Sensed Imagery

  • WANG Ziyu;ZHAO Shuhe;CHEN Xiuwan
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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    • pp.107-109
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    • 2004
  • High-resolution remotely sensed data such as SPOT-5 imagery are employed to study the effectiveness of the watershed segmentation algorithm. Existing problems in this approach are identified and appropriate solutions are proposed. As a case study, the panchromatic SPOT-5 image of part of Beijing urban areas has been segmented by using the MATLAB software. In segmentation, the structuring element has been firstly created, then the gaps between objects have been exaggerated and the objects of interest are converted. After that, the intensity valleys have been detected and the watershed segmentation have been conducted. Through this process, the objects in an image are divided into separate objects. Finally, the effectiveness of the watershed segmentation approach for high-resolution imagery has been summarized. The approach to solve the problems such as over-segmentation has been proposed.

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결합 유사성 척도를 이용한 시공간 영상 분할 (Spatio-temporal video segmentation using a joint similarity measure)

  • 최재각;이시웅;조순제;김성대
    • 한국통신학회논문지
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    • 제22권6호
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    • pp.1195-1209
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    • 1997
  • This paper presents a new morphological spatio-temporal segmentation algorithm. The algorithm incorporates luminance and motion information simultaneously, and uses morphological tools such as morphological filtersand watershed algorithm. The procedure toward complete segmentation consists of three steps:joint marker extraction, boundary decision, and motion-based region fusion. First, the joint marker extraction identifies the presence of homogeneours regions in both motion and luminance, where a simple joint marker extraction technique is proposed. Second, the spatio-temporal boundaries are decided by the watershed algorithm. For this purposek, a new joint similarity measure is proposed. Finally, an elimination ofredundant regions is done using motion-based region function. By incorporating spatial and temporal information simultaneously, we can obtain visually meaningful segmentation results. Simulation results demonstratesthe efficiency of the proposed method.

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A hierarchical semantic video object racking algorithm using mathematical morphology

  • Jaeyoung-Yi;Park, Hyun-Sang;Ra, Jong-Beom
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 1998년도 Proceedings of International Workshop on Advanced Image Technology
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    • pp.29-33
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    • 1998
  • In this paper, we propose a hierarchical segmentation method for tracking a semantic video object using a watershed algorithm based on morphological filtering. In the proposed method, each hierarchy consists of three steps: First, markers are extracted on the simplified current frame. Second, region growing by a modified watershed algorithm is performed for segmentation. Finally, the segmented regions are classified into 3 categories, i.e., inside, outside, and uncertain regions according to region probability values, which are acquired by the probability map calculated from a estimated motion field. Then, for the remaining uncertain regions, the above three steps are repeated at lower hierarchies with less simplified frames until every region is decided to a certain region. The proposed algorithm provides prospective results in video sequences such as Miss America, Clair, and Akiyo.

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적응적 Seed를 기초로한 분수계 분할을 이용한 차도영역 검출 (Robust Road Detection using Adaptive Seed based Watershed Segmentation)

  • 박한동;오정수
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2015년도 추계학술대회
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    • pp.687-690
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    • 2015
  • 전방 추돌 경보 시스템(FCWS) 및 차선 이탈 경보 시스템(LDWS)에서 차선 및 객체 검출을 위한 관심영역은 차도영역으로 설정되어야 한다. 분수계 분할(watershed segmentation)방법은 차도영역을 분리하기에 효과적인 알고리즘이다. 이 알고리즘은 초기 seed에 속해있는 watershed line과 국부 최소값에 따라서 분할 결과가 다르게 나타나는데 차도 seed에 그 이외의 영역이나 차량이 포함될 경우에 차도 이외의 부분이 차도영역으로 포함되어 분할된다. 이런 문제점을 보완하기 위해 도로 환경에 따라 차도 seed를 적응적으로 변경해야 한다. 그 방법으로 영상을 여러 개의 관심영역으로 분할하여 차선을 검출하고 자기차선을 잇는 직선을 초기 seed로 설정한다. 설정된 seed에 차량이 검출되면 seed 위치를 조정하고 조정된 위치에서 차선을 지나지 않는다면 차선을 지나도록 seed의 크기를 조정하여 최종적인 seed를 결정한다. 최종적으로 결정된 seed를 통해서 도로환경에 따라 적응적으로 차도영역을 검출을 가능하게 한다.

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유전자 알고리즘을 이용한 장·단기 유출모형의 매개변수 최적화 (Parameter Optimization of Long and Short Term Runoff Models Using Genetic Algorithm)

  • 김선주;지용근;김필식
    • 한국농공학회논문집
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    • 제46권5호
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    • pp.41-52
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    • 2004
  • In this study, parameters of long and short term runoff model were optimized using genetic algorithm as a basic research for integrated water management in a watershed. In case of Korea where drought and flood occurr frequently, the integrated water management is necessary to minimize possible damage of drought and flood. Modified TANK model was optimized as a long term runoff model and storage-function model was optimized as a short term runoff model. Besides distinguished parameters were applied to modified TANK model for supplementing defect that the model estimates less runoff in the storm period. As a result of application, simulated long and short term runoff results showed 7% and 5% improvement compared with before optimized on the average. In case of modified TANK model using distinguished parameters, the simulated runoff after optimized showed more interrelationship than before optimized. Therefore, modified TANK model can be applied for the long term water balance as an integrated water management in a watershed. In case of storage-function model, simulated runoff in the storm period showed high interrelationship with observed one. These optimized models can be applied for the runoff analysis of watershed.

SWMM의 유출량 보정을 위한 매개변수 최적화 (Parameter Optimization for Runoff Calibration of SWMM)

  • 조재현;이종호
    • 환경영향평가
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    • 제15권6호
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    • pp.435-441
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    • 2006
  • For the calibration of rainfall-runoff model, automatic calibration methods are used instead of manual calibration to obtain the reliable modeling results. When mathematical programming techniques such as linear programming and nonlinear programming are applied, there is a possibility to arrive at the local optimum. To solve this problem, genetic algorithm is introduced in this study. It is very simple and easy to understand but also applicable to any complicated mathematical problem, and it can find out the global optimum solution effectively. The objective of this study is to develope a parameter optimization program that integrate a genetic algorithm and a rainfall-runoff model. The program can calibrate the various parameters related to the runoff process automatically. As a rainfall-runoff model, SWMM is applied. The automatic calibration program developed in this study is applied to the Jangcheon watershed flowing into the Youngrang Lake that is in the eutrophic state. Runoff surveys were carried out for two storm events on the Jangcheon watershed. The peak flow and runoff volume estimated by the calibrated model with the survey data shows good agreement with the observed values.