• 제목/요약/키워드: shape detection

검색결과 990건 처리시간 0.028초

The Detection of Rectangular Shape Objects Using Matching Schema

  • Ye, Soo-Young;Choi, Joon-Young;Nam, Ki-Gon
    • Transactions on Electrical and Electronic Materials
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    • 제17권6호
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    • pp.363-368
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    • 2016
  • Rectangular shape detection plays an important role in many image recognition systems. However, it requires continued research for its improved performance. In this study, we propose a strong rectangular shape detection algorithm, which combines the canny edge and line detection algorithms based on the perpendicularity and parallelism of a rectangle. First, we use the canny edge detection algorithm in order to obtain an image edge map. We then find the edge of the contour by using the connected component and find each edge contour from the edge map by using a DP (douglas-peucker) algorithm, and convert the contour into a polyline segment by using a DP algorithm. Each of the segments is compared with each other to calculate parallelism, whether or not the segment intersects the perpendicularity intersecting corner necessary to detect the rectangular shape. Using the perpendicularity and the parallelism, the four best line segments are selected and whether a determined the rectangular shape about the combination. According to the result of the experiment, the proposed rectangular shape detection algorithm strongly showed the size, location, direction, and color of the various objects. In addition, the proposed algorithm is applied to the license plate detecting and it wants to show the strength of the results.

Frequency Domain Processing Techniques for Pulse Shape Modulated Ultra Wideband Systems

  • Gordillo, Alex Cartagena;Kohno, Ryuji
    • Journal of Communications and Networks
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    • 제9권4호
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    • pp.482-489
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    • 2007
  • In this paper, two frequency domain signal processing techniques for pulse shape modulation(PSM) ultra wideband(UWB) systems are presented. Firstly, orthogonal detection of UWB PSM Hermite pulses in frequency domain is addressed. It is important because time domain detection by correlation-based receivers is severely degraded by many sources of distortion. Pulse-shape, the information conveying signal characteristic, is deformed by AWGN and shape-destructive addition of multiple paths from the propagation channel. Additionally, because of the short nature of UWB pulses, timing mismatches and synchronism degrade the performance of PSM UWB communication systems. In this paper, frequency domain orthogonality of the Hermite pulses is exploited to propose an alternative detection method, which makes possible efficient detection of PSM in dense multipath channel environments. Secondly, a ranging method employing the Cepstrum algorithm is proposed. This method is partly processed in the frequency domain and can be implemented without additional hardware complexity in the terminal.

Randomized Hough 변환을 이용한 타원형 액적의 형상 검출 (Shape Detection of Ellipsoidal Droplets Using Randomized Hough Transform)

  • 추연준;강보선
    • 대한기계학회논문집B
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    • 제27권10호
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    • pp.1508-1515
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    • 2003
  • In this study, the image processing program for deducing parameters of the elliptic shape of the partially overlapped liquid droplets was developed using the randomized Hough transform and the parameter decomposition. The procedure for the shape detection consists of three steps. For the first step, the candidate centers of ellipses are determined by the geometric property of the ellipse. Next, the rest parameters are estimated by the randomized Hough transform. In the final step for the post-processing, optimally approximated parameters of ellipses are determined. The developed program was applied to the simulated overlapped ellipses, real overlapped droplets, and real spray droplets. The shape detection was very excellent unless there existed inherent problems in original images. Moreover, this method can be used as an effective separating method for the overlapped small particles.

Randomized Hough 변환을 이용한 타원형 액적의 형상 검출 (Shape Detection of Ellipsoidal Droplets Using Randomized Hough Transform)

  • 추연준;강보선
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.1783-1788
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    • 2003
  • In this study, the image processing program for deducing parameters of the elliptic shape of the partially overlapped liquid droplets was developed using the randomized Hough transform and the parameter decomposition. The procedure for the shape detection consists of three steps. For the first step, the candidate centers of ellipses are determined by the geometric property of the ellipse. Next, the rest parameters are estimated by the randomized Hough transform. In the final step for the post-processing, optimally approximated parameters of ellipses are determined. The developed program was applied to the simulated overlapped ellipses, real overlapped droplets, and real spray droplets. The shape detection was very excellent unless there existed inherent problems in original images. Moreover, this method can be used as an effective separating method for the overlapped small particles.

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DETECTION OF FRUITS ON NATURAL BACKGROUND

  • Limsiroratana, Somchai;Ikeda, Yoshio;Morio, Yoshinari
    • 한국농업기계학회:학술대회논문집
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    • 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.II
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    • pp.279-286
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    • 2000
  • The objective of this research is to detect the papaya fruits on tree in an orchard. The detection of papaya on natural background is difficult because colors of fruits and background such as leaves are similarly green. We cannot separate it from leaves by color information. Therefore, this research will use shape information instead. First, we detect an interested object by detecting its boundary using edge detection technique. However, the edge detection will detect every objects boundary in the image. Therefore, shape description technique will be used to describe which one is the interested object boundary. The good shape description should be invariant in scaling, rotating, and translating. The successful concept is to use Fourier series, which is called "Fourier Descriptors". Elliptic Fourier Descriptors can completely represent any shape, which is selected to describe the shape of papaya. From the edge detection image, it takes a long time to match every boundary directly. The pre-processing task will reduce non-papaya edge to speed up matching time. The deformable template is used to optimize the matching. Then, clustering the similar shapes by the distance between each centroid, papaya can be completely detected from the background.

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형태의 특징을 이용한 콘크리트 균열 검출 (Concrete crack detection using shape properties)

  • 조범석;김영로
    • 디지털산업정보학회논문지
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    • 제9권2호
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    • pp.17-22
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    • 2013
  • In this paper, we propose a concrete crack detection method using shape properties. It is based on morphology algorithm and crack features. We assume that an input image is contaminated by various noises. Thus, we use a morphology operator and extract patterns of crack. It segments cracks and background using opening and closing operations. Morphology based segmentation is better than existing integration methods using subtraction in detecting a crack it has small width. Also, it is robust to noisy environment. The proposed algorithm classifies the segmented image into crack and background using shape properties of crack. This method calculates values of properties such as the number of pixels and the maximum length of the segmented region. Also, pixel counts of clusters are considered. We decide whether the segmented region belongs to cracks according to those data. Experimental results show that our proposed crack detection method has better results than those by existing detection methods.

고유진동형의 웨이블렛 변환에 의한 선체 거더의 균열 진단에 관한 연구 (A Study on the Crack Detection Using the Wavelet Transformation of Mode Shape for Hull Girder)

  • 이대성;조대승
    • 대한조선학회논문집
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    • 제39권2호
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    • pp.19-27
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    • 2002
  • 대형 구조물의 결함 유무 및 결함 발생시의 위치 진단은 이들 구조물의 중대 손상으로 인한 인명 및 경제적 손실 예방에 매우 중요하다. 본 논문에서는 보유추 구조물에 결함이 존재할 경우 구조물의 모드 형상에 특이점으로 반영된다는 것에 착안하여, 결함으로 인한 보유추 구조물 고유진동형의 특이점을 고유진동형을 한번 웨이블렛 변환한 후 이의 상세 성분만을 역 웨이블렛 변환으로 복구한 값의 크기를 이용해서 찾는 방법에 대한 연구를 수행하였다. 본 연구에서 적용한 결함진단 방법의 타당성과 유용성은 두께 변화 또는 균열을 갖는 양단 자유 보에 대한 수치해석과 실험 및 균열을 갖는 선체 거더에 대한 수치해석을 수행하여 검토하였다.

Performance evaluation of wavelet and curvelet transforms based-damage detection of defect types in plate structures

  • Hajizadeh, Ali R.;Salajegheh, Javad;Salajegheh, Eysa
    • Structural Engineering and Mechanics
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    • 제60권4호
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    • pp.667-691
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    • 2016
  • This study focuses on the damage detection of defect types in plate structures based on wavelet transform (WT) and curvelet transform (CT). In particular, for damage detection of structures these transforms have been developed since the last few years. In recent years, the CT approach has been also introduced in an attempt to overcome inherent limitations of traditional multi-scale representations such as wavelets. In this study, the performance of CT is compared with WT in order to demonstrate the capability of WT and CT in detection of defect types in plate structures. To achieve this purpose, the damage detection of defect types through defect shape in rectangular plate is investigated. By using the first mode shape of plate structure and the distribution of the coefficients of the transforms, the damage existence, the defect location and the approximate shape of defect are detected. Moreover, the accuracy and performance generality of the transforms are verified through using experimental modal data of a plate.

역 투영과 휴 모멘트를 이용한 손영역 검출 및 모양 분류 (Hand Region Detection and hand shape classification using Hu moment and Back Projection)

  • 신재선;장대식
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2011년도 추계학술대회
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    • pp.911-914
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    • 2011
  • 손 영역을 찾는 것은 사용자 중심의 인터페이스를 제공하는 데 있어서 꼭 필요한 기술이며 이를 위해 많은 연구가 진행되어 왔다. 본 논문은 HSV 공간을 기반으로 한 역 투영 기법을 사용하여 손영역 검출을 수행하였으며, 휴 모멘트를 통해 추출된 손 영역을 분석, 손 모양 인식에 대한 방법을 제안한다. 역 투영 기법을 통해 손 영역 검출에 대한 신뢰도를 높였으며, 휴 모멘트를 통해 손모양을 구분할 수 있음을 확인하였다.

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선형레이저빔의 적응적 패턴 분할을 이용한 3차원 표면형상 측정 장치의 성능 향상에 관한 연구 (A Study on the Performance Improvement of a 3-D Shape Measuring System Using Adaptive Pattern Clustering of Line-Shaped Laser Light)

  • 박승규;백성훈;김대규;장원석;이일근;김철중
    • 한국정밀공학회지
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    • 제17권10호
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    • pp.119-124
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    • 2000
  • One of the main problems in 3D shape measuring systems that use the triangulation of line-shaped laser light is precise center line detection of line-shaped laser stripe. The intensity of a line-shaped laser light stripe on the CCD image varies following to the reflection angles, colors and shapes of objects. In this paper, a new center line detection algorithm to compensate the local intensity variation on a line-shaped laser light stripe is proposed. The 3-D surface shape measuring system using the proposed center line detection algorithm can measure 3-D surface shape with enhanced measurement resolution by using the dynamic shape reconstruction with adaptive pattern clustering of the line-shaped laser light. This proposed 3-D shape measuring system can be easily applied to practical situations of measuring 3-D surface by virtue of high speed measurement and compact hardware compositions.

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