• 제목/요약/키워드: Automatic thresholding

검색결과 95건 처리시간 0.025초

암모니아산화세균의 계수를 위한 영상분리기법 (A Segmentation Method for Counting Ammonia-oxidizing Bacteria)

  • 김학경;이선희;이명숙;김상봉
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.287-287
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    • 2000
  • As a method to control the bacteria number in adequate level, a real time control system based on microscope image processing measurement for the bacteria is adopted. For the experiment, Ammonia-oxidizing bacteria such as Acinetobacter sp. are used. This paper proposed hybrid method combined watershed algorithm with adaptive automatic thresholding method to enhance segmentation efficiency of overlapped image. Experiments was done to show the effectiveness of the proposed method compared to traditional Otsu's method, Otsu's method with adaptive automatic thresholding method and human visual method.

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자동 임계점 탐색 알고리즘과 통계적 투영 분석을 이용한 얼굴 분할 (Face seqmentation using automatic searching algorithm of thresholding value and statistical projection analysis)

  • 김장원;이흥복;김창석
    • 한국통신학회논문지
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    • 제21권8호
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    • pp.1874-1884
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    • 1996
  • In this paper, we proposed automatic searching algorithm of thresholding value using multilevel thresholding for face segmentation from input bust image effectively. The proposed algorithm extracted the thresholding value of brightness that is formed background region, face region and hair region without illumination, background and face size from input image. The statistical projection analysis project the brightness of multilevel thresholding image into horizontal and vertical direction and decide the thresholding value of face. And the algorithm extracted elliptical type block of face from input image in order to reduce the back ground region and hair region efficiently. The proposed algorithm can reduce searching area of feature extraction and processing time for face recognication.

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이웃 화소간 이차원 히스토그램 엔트로피 최대화를 이용한 명도영상 임계값 설정 (A New Automatic Thresholding of Gray-Level Images Based on Maximum Entropy of Two-Dimensional Pixel Histogram)

  • 김호연;남윤석;김혜규;박치항
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 추계종합학술대회 논문집(4)
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    • pp.77-80
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    • 2000
  • In this paper, we present a new automatic thresholding algorithm based on maximum entropy of two-dimensional pixel histogram. While most of the previous algorithms select thresholds depending only on the histogram of gray level itself in the image, the presented algorithm considers 2D relational histogram of gray levels of two adjacent pixels in the image. Thus, the new algorithm tends to leave salient edge features on the image after thresholding. The experimental results show the good performance of the presented algorithm.

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누적 유사도 측정을 이용한 자동 임계값 결정 기법 - 다중분광 및 초분광영상의 무감독 변화탐지를 목적으로 (Automatic Thresholding Method using Cumulative Similarity Measurement for Unsupervised Change Detection of Multispectral and Hyperspectral Images)

  • 김대성;김형태
    • 대한원격탐사학회지
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    • 제24권4호
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    • pp.341-349
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    • 2008
  • 본 논문은 위성영상을 이용한 변화정보를 취득하는데 있어 중요한 과정인 임계값 결정에 관한 새로운 기법을 제안하고 있다. 화소간 유사도 측정을 통해 도출된 결과 값을 일정 간격으로 누적 계산하고, 급격하게 변하는 지점을 임계값으로 결정하였다. 의사영상을 통해 기대최대화 기법, 교점방법과 성능을 비교하였으며, 두 시기의 ALI 영상과 Hyperion 영상에 실제 적용하여 변화탐지 결과를 확인하였다. 제안된 기법은 기존의 기법과 비슷한 수준의 변화탐지 결과 정확도를 확보할 수 있었으며, 기대최대화 기법에 비해 간단하게 적용할 수 있고, 교점방법과 달리 최빈 값을 둘 이상 가지는 히스토그램에도 적용할 수 있는 장점이 있어 향후 변화유무 정보 취득에 효과적으로 사용할 수 있을 것으로 기대한다.

다중센서-다중프레임 기반 표적분할기법 (A Target Segmentation Method Based on Multi-Sensor/Multi-Frame)

  • 이승연
    • 한국군사과학기술학회지
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    • 제13권3호
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    • pp.445-452
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    • 2010
  • Adequate segmentation of target objects from the background plays an important role for the performance of automatic target recognition(ATR) system. This paper presents a new segmentation algorithm using fuzzy thresholding to extract a target. The proposed algorithm consists of two steps. In the first step, the region of interest(ROI) including the target can be automatically selected by the proposed robust method based on the frame difference of each image sensor. In the second step, fuzzy thresholding with a proposed membership function is performed within the only ROI selected in the first step. The proposed membership function is based on the similarity of intensity and the adjacency of target area on each image. Experimental results applied to real CCD/IR images show a good performance and the proposed algorithm is expected to enhance the performance of ATR system using multi-sensors.

웨이브렛 변환과 자동적인 임계치 설정에 의한 미세 석회화 검출 (Microcalcification Extraction by Wavelet Transform and Automatic Thresholding)

  • 원철호;서용수;조진호
    • 한국멀티미디어학회논문지
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    • 제8권4호
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    • pp.482-491
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    • 2005
  • 본 논문에서는 디지털 X선 유방 촬영 시스템에서 획득된 영상으로부터 웨이브릿 변환과 자동적인 임계치 설정기법을 이용하여 미세 석회화 영역을 추출하였다. 디지털 X선 영상 장비는 임상 진단 분야에서는 필수적인 진단 장비이며, 흉부 촬영, 골절상 및 치아 교정 등의 다양한 분야에 사용되고 있다. 특히 디지털 X선 유방 촬영술은 유방암 진단의 가장 좋은 방법으로 알려져 있으며 최근 국내에서 디지털 X선 기기를 개발하기 위한 많은 연구들이 진행되고 있다. 본 논문에서는 디지털 X선 유방 촬영 영상으로부터 초기 단계의 유방암 진단을 위해 필수적인 미세 석회화를 검출하는 알고리즘을 제안하여 이를 효과적으로 검출하였으며 진단 방사선학적 진단에 도움을 줄 수 있음을 보였다.

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Automatic Visual Feature Extraction And Measurement of Mushroom (Lentinus Edodes L.)

  • Heon-Hwang;Lee, C.H.;Lee, Y.K.
    • 한국농업기계학회:학술대회논문집
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    • 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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    • pp.1230-1242
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    • 1993
  • In a case of mushroom (Lentinus Edodes L.) , visual features are crucial for grading and the quantitative evaluation of the growth state. The extracted quantitative visual features can be used as a performance index for the drying process control or used for the automatic sorting and grading task. First, primary external features of the front and back sides of mushroom were analyzed. And computer vision based algorithm were developed for the extraction and measurement of those features. An automatic thresholding algorithm , which is the combined type of the window extension and maximum depth finding was developed. Freeman's chain coding was modified by gradually expanding the mask size from 3X3 to 9X9 to preserve the boundary connectivity. According to the side of mushroom determined from the automatic recognition algorithm size thickness, overall shape, and skin texture such as pattern, color (lightness) ,membrane state, and crack were quantified and measured. A portion of t e stalk was also identified and automatically removed , while reconstructing a new boundary using the Overhauser curve formulation . Algorithms applied and developed were coded using MS_C language Ver, 6.0, PC VISION Plus library functions, and VGA graphic function as a menu driven way.

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Automatic Segmentation of Skin and Bone in CT Images using Iterative Thresholding and Morphological Image Processing

  • Kang, Ho Chul;Shin, Yeong-Gil;Lee, Jeongjin
    • IEIE Transactions on Smart Processing and Computing
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    • 제3권4호
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    • pp.191-194
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    • 2014
  • This paper proposes a fast and efficient method to extract the skin and bone automatically in CT images. First, the images were smoothed by applying an anisotropic diffusion filter to remove noise. The whole body was then detected by thresholding, which was set automatically. In addition, the contour of the skin was segmented using morphological operators and connected component labeling (CCL). Finally, the bone was extracted by iterative thresholding.

이미지 프로세싱을 위한 드릴 마모측정에 관한 연구

  • 양승배;김영일;유봉환
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1992년도 추계학술대회 논문집
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    • pp.298-301
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    • 1992
  • A digital image processing approach has been adopted to measure the flank wear area, which is very difficult to measure using conventional techniques. Automatic thresholding of the gray-level values of an image is very useful in automated analysis of image. 1-D entropy thresholding technique is used for image processing and analysis of the flank wear area. This strategy provides more information about drill wear conditions and should therefore have a higher reliability than previous methods. This study calulated quantitatively the flank were area of drill by computer program.

3차원 두뇌 자기공명영상의 자동 Segmentation 기법 (Automatic segmentation of 3-D brain MR images)

  • 허신;이철희
    • 대한의용생체공학회:학술대회논문집
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    • 대한의용생체공학회 1998년도 추계학술대회
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    • pp.60-61
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    • 1998
  • In this paper, we propose an algorithm for automatic segmentation of 3-dimesional brain MR images. In order to segment 3-dimensional brain MR images, we start segmentation from a mid-sagittal brain MR image. Then the segmented mid-sagittal brain MR image is used as a mask that is applied to the remaining lateral slices. Then we apply preprocessing, which includes thresholding and region-labeling, to the lateral slices, resulting in simplified 3-D brain MR images. Finally, we remove remaining problematic regions in the 3-dimensional brain MR image using the connectivity-based thresholding segmentation algorithm. Experiments show satisfactory results.

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