• 제목/요약/키워드: automatic edge detection

검색결과 133건 처리시간 0.024초

디지탈 혈관 조영상에서의 좌심실 경계 자동검출을 이용한 심박출 계수의 측정 (A Measurement of Heart Ejection Fraction using Automatic Detection of Left Ventricular Boundary in Digital Angiocardiogram)

  • 구본호;이태수
    • 대한의용생체공학회:의공학회지
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    • 제8권2호
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    • pp.177-188
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    • 1987
  • Detection of left ventricular boundary for the functional analysis of LV(left ventricle) is obtained using automatic boundary detection algorithm based on dynamic program ming method. This scheme reduces the edge searching time and ensures connective edge detection, since it does not require general edge operator, edge thresholding and linking process of other edge detection methods. The left ventricular diastolic volume and systolic volume were computed after this automatic boundary detection, and these volume data were applied to analyze LV ejection fraction.

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디지탈 혈관 조영장치를 이용한 실시간 영상처리와 심장파라미터의 측정 (Real time image processing and measurement of heart parameter using digital subtraction angiography)

  • 신동익;구본호;박광석;민병구;한만청
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 26-27 Oct. 1990
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    • pp.570-574
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    • 1990
  • Detection of left ventricular boundary for the functional analysis of LV(left ventricle)is obtained using automatic boundary detection algorithm based on dynamic programming method. This scheme reduces the edge searching time and ensures connective edge detection, since it does not require general edge operator, edge thresholding and linking process of other edge. detection methods. The left ventricular diastolic volume and systolic volume and systolic volume were computed after this automatic boundary detection, and these Volume data wm applied to analyze LV ejection fraction.

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Ramp Edge Detection을 이용한 끝점 검출과 음절 분할에 관한 연구 (A Study on Endpoint Detection and Syllable Segmentation System Using Ramp Edge Detection)

  • 유일수;홍광석
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅳ
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    • pp.2216-2219
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    • 2003
  • Accurate speech region detection and automatic syllable segmentation is important part of speech recognition system. In automatic speech recognition system, they are needed for the purpose of accurate recognition and less computational complexity, In this paper, we Propose improved syllable segmentation method using ramp edge detection method and residual signal Peak energy. These methods were used to ensure accuracy and robustness for endpoint detection and syllable segmentation system. They have almost invariant response to various background noise levels. As experimental results, we obtained the rate of 90.7% accuracy in syllable segmentation in a condition of accurate endpoint detection environments.

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저속 카메라 통신용 자동 디스플레이 검출을 위한 Lambertian 색상 분할 및 Canny Edge Detection 알고리즘 연구 (A Study on Lambertian Color Segmentation and Canny Edge Detection Algorithms for Automatic Display Detection in CamCom)

  • 한정도;누그마노브 사이드;이바딤;차재상
    • 한국정보전자통신기술학회논문지
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    • 제11권5호
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    • pp.615-622
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    • 2018
  • 최근 가시광원을 사용하는 카메라 통신 기술의 발전과 더불어 디스플레이를 통해 가시광 데이터를 표출하고 이를 인식하는 기술에 대한 수요가 증가하고 있다. 기존의 디스플레이 기반 CamCom 기법은 사용자가 설정한 RoI 영역 기반의 2차원 컬러코드를 인식하는 방식을 사용하였으나, 이는 보행 상황 등 수신위치가 변동되는 상황에 적합하지 않은 단점이 존재한다. 이에 본 논문에서는 카메라 통신에서 자동 RoI 설정을 위해 적용될 수 있는 Lambertian 색상 분할과 Canny 엣지 검출이 결합된 알고리즘 기반의 자동 디스플레이 검출 기법에 대하여 제안하였다. 기존 디스플레이 검출 기법은 디스플레이에서 표출되고 있는 콘텐츠의 변화가 발생하면 검출율이 현저히 감소하는 문제점이 존재하며, 본 논문에서는 이를 해결하기 위하여 lambertian 색상 분할 및 canny 엣지 검출을 결합한 알고리즘 적용을 통헤 자동으로 디스플레이를 검출 할 수 있는 기법을 제안하였다. 본 연구에서는 디스플레이 엣지 인식을 위해 사용되는 다양한 알고리즘을 분석하고 변화하는 컬러코드 콘텐츠 인식시 성능을 측정하였으며, 제안한 저속 카메라 통신용 자동 디스플레이 검출을 위한 lambertian 색상 분할 및 Canny Edge Detection 알고리즘을 적용한 실험 결과 약 96%의 검출율을 달성함을 확인하였다.

디지탈 이미지프로세싱을 이용한 자동외관검사장치 개발 (System Development for Automatic Form Inspecion by Digital Image Processing)

  • 유봉환
    • 한국생산제조학회지
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    • 제5권2호
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    • pp.57-62
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    • 1996
  • Basically, the idea underlying most edge-detection technique is the computation of a local derivative operator used for edge detection in gray level image. This concept can be easily illustrated with the aid of object which shows an image of a simple lilght on a dark background, Using the gray level profile along a horizontal scan line of the image. the first and second derivatives of it were acquired. This study is to develop an automatic measuring system based on the digital image processing which can be applied to the real time measurement of the characteristics of the ultra-thin thickness. The experimental results indicate that the developed automatic inspection can be applied in real situation.

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이동로봇을 위한 영상의 자동 엣지 검출 방법 (Automatic Edge Detection Method for Mobile Robot Application)

  • 김동수;권인소;이왕헌
    • 제어로봇시스템학회논문지
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    • 제11권5호
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    • pp.423-428
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    • 2005
  • This paper proposes a new edge detection method using a $3{\times}3$ ideal binary pattern and lookup table (LUT) for the mobile robot localization without any parameter adjustments. We take the mean of the pixels within the $3{\times}3$ block as a threshold by which the pixels are divided into two groups. The edge magnitude and orientation are calculated by taking the difference of average intensities of the two groups and by searching directional code in the LUT, respectively. And also the input image is not only partitioned into multiple groups according to their intensity similarities by the histogram, but also the threshold of each group is determined by fuzzy reasoning automatically. Finally, the edges are determined through non-maximum suppression using edge confidence measure and edge linking. Applying this edge detection method to the mobile robot localization using projective invariance of the cross ratio. we demonstrate the robustness of the proposed method to the illumination changes in a corridor environment.

B 모드 단축 심초음파 영상의 좌심실 내벽 윤곽선 자동 검출 (Automatic Detection of Left Ventricular Endocardial Boundary on B-mode Short Axis Echocardiography)

  • 김명남;원철호;조진호
    • 전자공학회논문지B
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    • 제32B권10호
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    • pp.1294-1304
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    • 1995
  • In this paper, a method has been proposed for the fully automatic detection of left ventricular endocardial boundary in B-mode short axis echocardiography without manual intervention by human operator. The proposed method makes use of the weighted model that approximates to endocardium and incomplete edge information for echocardiography. Therefore, this method is more effective than boundary detection by only edge information. The implementation of this method is as follows. First, the proposed algorithms are used in order to detect the approximate boundary, then a weighted model with the approximate boundary is constructed. Finally, the cavity center of the left ventricle performing the Hough transform with the weighted model and edge image can be found automatically, and then the endocardial boundary using detected center, original image, weighted model, and edge image can be detected. validations of this method with experimental results on echo image of dog's heart and clinical echocardiography is verified.

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잡음추측을 이용한 자동적인 에지검출 문턱값 선택과 그 응용 (Automatic threshold selection for edge detection using a noise estimation scheme and its application)

  • 김형수;오승준
    • 한국통신학회논문지
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    • 제21권3호
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    • pp.553-563
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    • 1996
  • Detecting edges is one of issues with essentialimprotance in the area of image analysis. An edge in an image is a boundary or contour at which a significant change occurs in image intensity. Edge detection has been studied in many addlications such as imagesegmentation, robot vision, and image compression. In this paper, we propose an automatic threshold selection scheme for edge detection and show its application to noise elimination. The scheme suggested here applied statistical properties of the noise estimated from a noisy image to threshold selection. Since a selected threshold value in the scheme depends on not the characgreistic of an orginal image but the statistical feature of added noise, we can remove ad-hoc manners used for selecting the threshold value as well as decide the value theoretically. Furthermore, that shceme can reduce the number of edge pixels either generated or lost by noise. an application of the scheme to noise elimination is shown here. Noise in the input image can be eliminated with considering the direction of each edge pixedl on the edge map obtained by applying the threshold selection scheme proposed in this paper. Achieving significantly improved results in terms of SNR as well as subjective quality, we can claim that the suggested method works well.

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에지 방향 지도와 영역 컬러 정보를 이용한 얼굴 추출 기법 (Face Detection Using Edge Orientation Map and Local Color Information)

  • 김재협;문영식
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2005년도 추계종합학술대회
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    • pp.987-990
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    • 2005
  • An important issue in the field of face recognitions and man-machine interfaces is an automatic detection of faces in visual scenes. it should be computationally fast enough to allow an online detection. In this paper we describe our ongoing work on face detection that models the face appearance by edge orientation and color distribution. We show that edge orientation is a powerful feature to describe objects like faces. We present a method for face region detection using edge orientation and a method for face feature detection using local color information. We demonstrate the capability of our detection method on an image database of 1877 images taken from more than 700 people. The variations in head size, lighting and background are considerable, and all images are taken using low-end cameras. Experimental results show that the proposed scheme achieves 94% detection rate with a resonable amount of computation time.

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누적 히스토그램과 에지 정보를 이용한 장면 전환 검출 (Scene Change Detection Using Cumulative Histogram and Edge Information)

  • 황두선;이종설;조위덕;문영식
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 하계종합학술대회 논문집(3)
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    • pp.211-214
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    • 2002
  • Automatic video partitioning is the first step for content-based indexing and retrieval of video data. In this paper, an efficient algorithm for scene change detection is proposed, where cumulative histogram and edge information are utilized. Experimental results have shown the effectiveness of the proposed algorithm.

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