• Title/Summary/Keyword: Sobel method

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A Study on Real-time Tracking Method of Horizontal Face Position for Optimal 3D T-DMB Content Service (지상파 DMB 단말에서의 3D 컨텐츠 최적 서비스를 위한 경계 정보 기반 실시간 얼굴 수평 위치 추적 방법에 관한 연구)

  • Kang, Seong-Goo;Lee, Sang-Seop;Yi, June-Ho;Kim, Jung-Kyu
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.48 no.6
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    • pp.88-95
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    • 2011
  • An embedded mobile device mostly has lower computation power than a general purpose computer because of its relatively lower system specifications. Consequently, conventional face tracking and face detection methods, requiring complex algorithms for higher recognition rates, are unsuitable in a mobile environment aiming for real time detection. On the other hand, by applying a real-time tracking and detecting algorithm, we would be able to provide a two-way interactive multimedia service between an user and a mobile device thus providing a far better quality of service in comparison to a one-way service. Therefore it is necessary to develop a real-time face and eye tracking technique optimized to a mobile environment. For this reason, in this paper, we proposes a method of tracking horizontal face position of a user on a T-DMB device for enhancing the quality of 3D DMB content. The proposed method uses the orientation of edges to estimate the left and right boundary of the face, and by the color edge information, the horizontal position and size of face is determined finally to decide the horizontal face. The sobel gradient vector is projected vertically and candidates of face boundaries are selected, and we proposed a smoothing method and a peak-detection method for the precise decision. Because general face detection algorithms use multi-scale feature vectors, the detection time is too long on a mobile environment. However the proposed algorithm which uses the single-scale detection method can detect the face more faster than conventional face detection methods.

Dempster-Shafer's Evidence Theory-based Edge Detection

  • Seo, Suk-Tae;Sivakumar, Krishnamoorthy;Kwon, Soon-Hak
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.11 no.1
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    • pp.19-24
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    • 2011
  • Edges represent significant boundary information between objects or classes. Various methods, which are based on differential operation, such as Sobel, Prewitt, Roberts, Canny, and etc. have been proposed and widely used. The methods are based on a linear convolution of mask with pre-assigned coefficients. In this paper, we propose an edge detection method based on Dempster-Shafer's evidence theory to evaluate edgeness of the given pixel. The effectiveness of the proposed method is shown through experimental results on several test images and compared with conventional methods.

An Edge Detection Method for Gray Scale Images Based on their Fuzzy System Representation

  • Moon, Byung-Soo;Lee, Hyun-Chul;Kim, Jang-Yeol
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2001.12a
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    • pp.283-286
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    • 2001
  • Based on a fuzzy system representation of gray scale images, we derive an edge detection algorithm whose convolution kernel is different from the known kernels such as those of Roberts', Prewitt's or Sobel's gradient. Our fuzzy system representation is an exact representation of the bicubic spline function which represents the gray scale image approximately. Hence the fuzzy system is a continuous function and it provides a natural way to define the gradient and the Laplacian operator. We show that the gradient at grid points can be evaluated by taking the convolution of the image with a 3 3 kernel. We also show that our gradient coupled with the approximate value of the continuous function generates an edge detection method which creates edge images clearer than those by other methods. A few examples of applying our methods are included.

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Recognition of Passports using CDM Masking and ART2-based Hybrid Network

  • Kim, Kwang-Baek;Cho, Jae-Hyun;Woo, Young-Woon
    • Journal of information and communication convergence engineering
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    • v.6 no.2
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    • pp.213-217
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    • 2008
  • This paper proposes a novel method for the recognition of passports based on the CDM(Conditional Dilation Morphology) masking and the ART2-based RBF neural networks. For the extraction of individual codes for recognizing, this paper targets code sequence blocks including individual codes by applying Sobel masking, horizontal smearing and a contour tracking algorithm on the passport image. Individual codes are recovered and extracted from the binarized areas by applying CDM masking and vertical smearing. This paper also proposes an ART2-based hybrid network that adapts the ART2 network for the middle layer. This network is applied to the recognition of individual codes. The experiment results showed that the proposed method has superior in performance in the recognition of passport.

ESPI Simulation for the Vibration Modes of the Thin Right-Angled Plate (얇은 직각판의 진동 모드에 대한 ESPI 시뮬레이션)

  • 장순석
    • Journal of KSNVE
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    • v.9 no.3
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    • pp.509-516
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    • 1999
  • The ESPI (Electronic Speckle Pattern Interferometry) algorithm has been simulated to calculate vibrational modes of a thin right-angled STS304 plate. The phase transformation of the reference wave of the ESPI is carried out only one time during vibration in order to clarify ESPI speckle patterns. Two dimensional vibrational modes are calculated from one ESPI pattern before vibration onset and two ESPI patterns during vibrations but with and without the phase transformation. The ESPI harmonic results are compared with those derived from the finite element method (FEM), and they agree very well. Additionally a phase unwrapping algorithm has been newly developed to derive a displacement map from an ESPI phase map.

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3D View Synthesis with Feature-Based Warping

  • Hu, Ningning;Zhao, Yao;Bai, Huihui
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.11
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    • pp.5506-5521
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    • 2017
  • Three-dimensional video (3DV), as the new generation of video format standard, can provide the viewers with a vivid screen sense and a realistic stereo impression. Meanwhile the view synthesis has become an important issue for 3DV application. Differently from the conventional methods based on depth, in this paper we propose a new view synthesis algorithm, which can employ the correlation among views and warp in the image domain only. There are mainly two contributions. One is the incorporation of sobel edge points into feature extraction and matching, which can obtain a better stable homography and then a visual comfortable synthesis view compared to SIFT points only. The other is a novel image blending method proposed to obtain a better synthesis image. Experimental results demonstrate that the proposed method can improve the synthesis quality both in subjectivity and objectivity.

A Hybrid Automatic Focusing Method with Gaussian Interpolation and Adaptive Step Size (가우시안보간과 적응스텝크기를 적용한 하이브리드 오토포커싱)

  • Moon, Soon Hwan;Kim, Gyung Bum
    • Journal of the Semiconductor & Display Technology
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    • v.13 no.1
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    • pp.51-55
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    • 2014
  • In this paper, an hybrid automatic focusing method has been proposed for speedy and reliable measurement and inspection in industry. It can improve reliability of focusing position by using not a focusing measure but the hybrid one that is incorporated with sobel operator and auto-correlation. Also, it can not only reduce control time of focusing position using adaptive step size, but also improve accuracy of focusing position by gaussian interpolation. Its performance is verified by experiments. It is expected that it can apply to optical system for measurement and inspection in industry fields.

Statistical Tests for Edg Detection (에지 검출을 위한 통계적 검정법)

  • Im, Dong-Hun;Seong, Sin-Hui
    • The Transactions of the Korea Information Processing Society
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    • v.7 no.3
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    • pp.1021-1024
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    • 2000
  • In this paper we describe a nonparametric Wilcoxon test and a parametric Z test based on statistical hypothesis testing for the detection of edges. We use the threshold determined by specifying significance level $\alpha$, while Bovik, Huang and Munson[4] consider the range of possible values of test statistics for the threshold. From the experimental results of edge detection, the Z method performs sensitively to the noisy image, while the Wilcoxon method is robust over both noisy nd noise-free images. Comparison with our statistical tests and Sobel operator shows that our tests perform more effectively in both noisy and noise-free images.

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A Study on Edge Detection Algorithm using Modified Mask in Salt and Pepper Noise Images (Salt and Pepper 잡음 영상에서 변형된 마스크를 이용한 에지 검출 알고리즘에 관한 연구)

  • Lee, Chang-Young;Kim, Nam-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.1
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    • pp.210-216
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    • 2014
  • The edge in the image is a part which the brightness changes rapidly between the object and the object or objects and background, and includes information of the features such as size, position, orientation, and texture of the object. The edge detection is the technique that acquires these information of the images, and now the researches to detect edges are making steady progress. Typical conventional edge detection methods are Sobel, Prewitt, Roberts using the first derivative operator and Laplacian method using the second derivative operator and so on. These methods is more or less insufficient that the characteristics of the edge detection in the image added salt and pepper noise. therefore, in this paper, an edge detection algorithm using modified mask that applies different size mask according to noise density of local mask is proposed.

Convergence Study on Mediating Effect of Clinical Competence on the Relationship between Grit and Retention Intention among New Graduate Nurses (신규간호사의 그릿과 재직의도의 관계에서 임상수행능력의 매개효과에 대한 융복합적 연구)

  • Ko, Jin-Hee;Gu, Mee-Ock
    • Journal of the Korea Convergence Society
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    • v.11 no.4
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    • pp.369-380
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    • 2020
  • This study was conducted to examinate the mediating effect of clinical competence on the relationship between grit and retention intention among new graduate nurses. Participants were 232 nurses working at hospitals with over 300 beds in Korea. Data were analyzed using descriptive statistics, t-test, one-way ANOVA, Pearson's correlation coefficients, and multiple regression following the Baron and Kenny method and Sobel test for mediation. As a result, There were significant relationships between grit and clinical competence(r=.38, p=.011), grit and retention intention(r=.32, p=.016), and clinical competence and retention intention(r=.33, p<.001). Clinical competence showed partial mediating effect in the relationship between grit and retention intention(z=3.14, p<.001). The results of this study suggest that interventions enhancing grit would be useful to improve retention intention of new graduate nurses.