• Title/Summary/Keyword: shape detection

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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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    • v.17 no.6
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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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    • v.9 no.4
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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.

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

  • Choo, Yeon-Jun;Kang, Bo-Seon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.27 no.10
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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.

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

  • Choo, Yeon-Jun;Kang, Bo-Seon
    • Proceedings of the KSME Conference
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    • 2003.04a
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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
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 2000.11b
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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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Concrete crack detection using shape properties (형태의 특징을 이용한 콘크리트 균열 검출)

  • Joh, Beom Seok;Kim, Young Ro
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.9 no.2
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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.

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

  • Dae-Sung Lee;Dae-Seung Cho
    • Journal of the Society of Naval Architects of Korea
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    • v.39 no.2
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    • pp.19-27
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    • 2002
  • The early damage detection of large structures is very important to prevent the disaster due to its global failure. In this paper, a crack detection method of the beam-analogy structure based on the wavelet transformation of mode shape is presented. The method can effectively detect the singularity of mode shape caused to the inconsistency of bending moment and shear force at the damaged part using the discrete wavelet of mode shape and its inverse transforms of detail components. To investigate the validity and the applicability of the presented damage detection method, numerical simulation and experiment are carried out for the idealized beam and the real ship structures.

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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    • v.60 no.4
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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.

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

  • Shin, Jae-Sun;Jang, Dae-Sik
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2011.10a
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    • pp.911-914
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    • 2011
  • Detecting Hand Region is essencial technology to providing User based interface and many research has been continue. In this paper will propose Hand Region Detection method by using HSV space based on Back Projection and Hand Shape Recognition using Hu Moment. By using Back Projection, I updated reliability on Hand Region Detection by Back Projection method and, Confirmed Hand Shape could be recognized through Hu moment.

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

  • Park, Seung-Gyu;Baek, Seong-Hun;Kim, Dae-Gyu;Jang, Won-Seok;Lee, Il-Geun;Kim, Cheol-Jung
    • Journal of the Korean Society for Precision Engineering
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    • v.17 no.10
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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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