• 한국농공학회논문집
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• 제48권4호
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• pp.3-12
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• 2006

Watershed is the land area that contributes runoff to an outlet point. To delineate an watershed, watershed delineation using GIS that contains grid data structure is the most general method. Some researchers have studied to implement algorithms that revise the TIN topography since it is difficult to delineate watershed boundary more accurately. In this study kruskal's greedy algorithm and triangulated irregular network (TIN) were used to delineate a watershed. This method does not require a conversion from to DEM in grid and automatically obtain(generates) the oulet points. Delineation algorithm was tested in Geosan-gun, Chung-cheongbuk-do and get small watershed areas. Finally, kruskal's algorithm could operate more precisely with revision algorithm.

• JSTS:Journal of Semiconductor Technology and Science
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• 제12권2호
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• pp.175-185
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• 2012

Predictive watershed transform is a popular object segmentation algorithm which achieves a speed-up by identifying image regions that are different from the previous frame and performing object segmentation only for those regions. However, incorrect segmentation is often generated by the predictive watershed transform which uses only local information in merge-split decision on boundary regions. This paper improves the predictive watershed transform to increase the accuracy of segmentation results by using the additional information about the root of boundary regions. Furthermore, the proposed algorithm is processed in a block-based manner such that an image frame is decomposed into blocks and each block is processed independently of the other blocks. The block-based approach makes it easy to implement the algorithm in hardware and also permits an extension for parallel execution. Experimental results show that the proposed watershed transform produces more accurate segmentation results than the predictive watershed transform.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2006년도 하계종합학술대회
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• pp.299-300
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• 2006

In this paper, we propose a segmentation algorithm which combines the ideas from local watershed transforms and the region merging algorithm based hierarchical queue. Only the process of watershed and region merging algorithm can be restricted area. A fast region merging approach is proposed to extract the video object from the regions of watershed segmentation. Results show the effectiveness and convenience of the approach.

• International Journal of Internet, Broadcasting and Communication
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• 제11권1호
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• pp.39-46
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• 2019

This paper proposes an adaptive threshold watershed algorithm, which is the method used for image segmentation and boundary detection, which extends the region on the basis of regional minimum point. First, apply adaptive thresholds to determine regional minimum points. Second, it extends the region by applying adaptive thresholds based on determined regional minimum points. Traditional watershed algorithms create over-segmentation, resulting in the disadvantages of breaking boundaries between regions. These segmentation results mainly from the boundary of the object, creating an inaccurate region. To solve these problems, this paper applies an improved watershed algorithm applied with adaptive threshold in regional minimum point search and region expansion in order to reduce over-segmentation and breaking the boundary of region. This resulted in over-segmentation suppression and the result of having the boundary of precisely divided regions. The experimental results show that the proposed algorithm can apply adaptive thresholds to reduce the number of segmented regions and see that the segmented boundary parts are correct.

• 융합신호처리학회논문지
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• 제12권2호
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• pp.91-95
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• 2011

In this paper, we present an improved multi-scale gradient algorithm. The proposed algorithm works the effectively handling of both step and blurred edges. In the proposed algorithm, the image sharpening operator is sharpening the edges and contours of the objects. This operation gives an opportunity to get noise reduced image and step edged image. After that, multi-scale gradient operator works on noise reduced image in order to get a gradient image. The gradient image is segmented by watershed transform. The approach of region merging is used after watershed transform. The region merging is carried out according to the region area and region homogeneity. The region number of the proposed algorithm is 36% shorter than that of the existing algorithm because the proposed algorithm produces a few irrelevant regions. Moreover, the computational time of the proposed algorithm is relatively fast in comparison with the existing one.

• 한국정보통신학회논문지
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• 제21권2호
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• pp.409-415
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• 2017

본 논문은 watershed를 이용한 차도 분할 알고리즘을 제안하고 있다. 제안된 알고리즘은 차량과 차선 정보를 이용해 차도 마커와 배경 마커를 자동 생성하는 automatic marked watershed를 이용한 영역 분할 알고리즘이고 이는 지나치게 많은 영역이나 마커를 위한 수작업 같은 watershed 기반 영역 분할의 문제점들을 해결할 수 있다. 차도 마커는 차선은 포함되나 차량은 배제되는 순수한 차도 영역을 위한 속성을 포함하고 배경 마커는 차량과 배경을 포함하는 나머지 영역을 위한 속성을 포함하고 있다. 실제 도로 영상에 적용된 영역 분할 결과들은 제안된 알고리즘은 다양한 환경에서 적절한 마커들을 생성할 수 있고, 주행 차로와 양옆 차로를 포함한 필수 차도 영역을 적절하게 분할할 수 있는 것을 보여주고, 성능 면에 있어서는 제안된 알고리즘은 수작업으로 생성된 마커를 사용한 기존 알고리즘과 대등함을 보여준다.

• 한국멀티미디어학회논문지
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• 제17권10호
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• pp.1171-1181
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• 2014

In this paper, we propose improved methods which are image conversion and extraction method of watershed seed using morphological characteristic of teeth on complement image. Conventional tooth segmentation methods are occurred low detection ratio at molar region and over, overlap segmentation owing to specular reflection and morphological feature of molars. Therefore, in order to solve the problems of the conventional methods, we propose the image conversion method and improved extraction method of watershed seed. First, the image conversion method is performed using RGB, HSI space of tooth image for to extract boundary and seed of watershed efficiently. Second, watershed seed is reconstructed using morphological characteristic of teeth. Last, individual tooth segmentation is performed using proposed seed of watershed by watershed algorithm. Therefore, as a result of comparison with marker controlled watershed algorithm and the proposed method, we confirmed higher detection ratio and accuracy than marker controlled watershed algorithm.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(3)
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• pp.59-62
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• 2002

Watershed Segmentation with Multiple Merging Conditions in Region Growing Process The watershed segmentation method holds the merits of edge-based and region-based methods together, but still shows some problems such as over segmentation and merging fault. We propose an algorithm which overcomes the problems of the watershed method and shows efficient performance for .general images, not for specific ones. The algorithm segments or merges regions by thresholding the depths of the catchment basins, the similarities and the sizes of the regions. The experimental results shows the reduction of the number of the segmented regions that are suitable to human visual system and consciousness.

• International Journal of Contents
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• 제10권3호
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• pp.35-40
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• 2014

Text line segmentation is a critical task in handwritten document recognition. In this paper, we propose a novel text-line-segmentation method using baseline estimation and watershed. The baseline-detection algorithm estimates the baseline using Adaptive Head-Tail Connection (AHTC) on the document. Then, the watershed method segments the line region using the baseline-detection result. Finally, the text lines are separated by watershed result and a post-processing algorithm defines the lines more correctly. The scheme successfully segments text lines with 97% accuracy from the handwritten document images in the ICDAR database.

• 대한원격탐사학회지
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• 제18권2호
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• pp.107-116
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• 2002

Watershed 알고리듬을 통해 에지 기반과 영역 기반 기법을 결합한 하이브리드 영상 분할 알고리듬을 제안하였다. 먼저 minimax flow와 결합된 평균 곡률 확산을 이용하여 에지를 보존하면서 잡음을 제거를 수행한다. 영상을 watershed 알고리듬을 이용하여 분할한 후에 RAG (Region Adjacency Graph)을 사용하여 분할된 영역들간의 관계를 분석한다. RAG의 그래프 노드와 에지 비용은 분할된 영역과 두 인접한 영역사이의 상이함을 나타낸다. 최소 비용의 RAG의 에지를 찾아 가장 유사한 영역 쌍이 결정되면 두 영역은 서로 합치고 RAG은 갱신된다. 제안한 방법을 통해서 잡음을 효과적으로 감소시키고 한 화소 두께의, 닫힌 경계선을 획득할 수 있었다.