• Title/Summary/Keyword: invariant moment

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A Study on the Automatic Inspection System using Invariant Moments Algorithm with the Change of Size and Rotation (크기와 회전 변화에 불변 모멘트 알고리즘을 이용한 자동 검사 시스템에 관한 연구)

  • Lee, Yong-Joong
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.13 no.3
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    • pp.37-43
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    • 2004
  • The purpose of this study is to develop a practical image inspection system that could recognize it correctly, endowing flexibility to the productive field, although the same object for work will be changed in the size and rotated. In this experiment, it selected a fighter, rotating the direction from $30^{\circ}$ to $45^{\circ}$ simultaneously while changing the size from 1/4 to 1/16, as an object inspection without using another hardware for exclusive image processing. The invariant moments, Hu has suggested, was used as feature vector moment descriptor. As a result of the experiment, the image inspection system developed from this research was operated in real-time regardless of the chance of size and rotation for the object inspection, and it maintained the correspondent rates steadily above from 94% to 96%. Accordingly, it is considered as the flexibility can be considerably endowed to the factory automation when the image inspection system developed from this research is applied to the productive field.

A Shape Based Image Retrieval Method using Phase of ART (ART의 위상 정보를 이용한 형태기반 영상 검색 방법)

  • Lee, Jong-Min;Kim, Whoi-Yul
    • Journal of Broadcast Engineering
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    • v.17 no.1
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    • pp.26-36
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    • 2012
  • Since shape of an object in an image carries important information in contents based image retrieval (CBIR), many shape description methods have been proposed to retrieve images using shape information. Among the existing shape based image retrieval methods, the method which employs invariant Zernike moment desciptor (IZMD) showed better performance compared to other methods which employ traditional Zernike moments descriptor in CBIR. In this paper, we propose a new image retrieval method which applies invariant angular radial transform descriptor (IARTD) to obtain higher performance than the method which employs IZMD in CBIR. IARTD is a rotationally invariant feature which consists of magnitudes and alligned phases of angular radial transform coefficients. To produce rotationally invariant phase coefficients, a phase correction scheme is performed while extracting the IARTD. The distance between two IARTDs is defined by combining the differences of the magnitudes and the aligned phases. Through the experiment using MPEG-7 shape dataset, the average bull's eye performance (BEP) of the proposed method is 0.5806 while the average BEPs of the exsiting methods which employ IZMD and traditional ART are 0.4234 and 0.3574, respectively.

Pattern Recognition with Rotation Invariant Multiresolution Features

  • Rodtook, S.;Makhanov, S.S.
    • 제어로봇시스템학회:학술대회논문집
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    • 2004.08a
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    • pp.1057-1060
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    • 2004
  • We propose new rotation moment invariants based on multiresolution filter bank techniques. The multiresolution pyramid motivates our simple but efficient feature selection procedure based on the fuzzy C-mean clustering, combined with the Mahalanobis distance. The procedure verifies an impact of random noise as well as an interesting and less known impact of noise due to spatial transformations. The recognition accuracy of the proposed techniques has been tested with the preceding moment invariants as well as with some wavelet based schemes. The numerical experiments, with more than 30,000 images, demonstrate a tangible accuracy increase of about 3% for low noise, 8% for the average noise and 15% for high level noise.

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A New Shape Adaptation Scheme to Affine Invariant Detector

  • Liu, Congxin;Yang, Jie;Zhou, Yue;Feng, Deying
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.4 no.6
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    • pp.1253-1272
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    • 2010
  • In this paper, we propose a new affine shape adaptation scheme for the affine invariant feature detector, in which the convergence stability is still an opening problem. This paper examines the relation between the integration scale matrix of next iteration and the current second moment matrix and finds that the convergence stability of the method can be improved by adjusting the relation between the two matrices instead of keeping them always proportional as proposed by previous methods. By estimating and updating the shape of the integration kernel and differentiation kernel in each iteration based on the anisotropy of the current second moment matrix, we propose a coarse-to-fine affine shape adaptation scheme which is able to adjust the pace of convergence and enable the process to converge smoothly. The feature matching experiments demonstrate that the proposed approach obtains an improvement in convergence ratio and repeatability compared with the current schemes with relatively fixed integration kernel.

ON STAR MOMENT SEQUENCE OF OPERATORS

  • Park, Sun-Hyun
    • Honam Mathematical Journal
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    • v.29 no.4
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    • pp.569-576
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    • 2007
  • Let $\cal{H}$ be a separable, infinite dimensional, complex Hilbert space. We call "an operator $\cal{T}$ acting on $\cal{H}$ has a star moment sequence supported on a set K" when there exist nonzero vectors u and v in $\cal{H}$ and a positive Borel measure ${\mu}$ such that <$T^{*j}T^ku$, v> = ${^\int\limits_{K}}\;{{\bar{z}}^j}\;{{\bar{z}}^k}\;d\mu$ for all j, $k\;\geq\;0$. We obtain a characterization to find a representing star moment measure and discuss some related properties.

A Iris Recognition Using Zernike Moment and Wavelet (Zernike 모멘트와 Wavelet을 이용한 홍채인식)

  • Choi, Chang-Soo;Park, Jong-Cheon;Jun, Byoung-Min
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.11
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    • pp.4568-4575
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    • 2010
  • Iris recognition is a biometric technology that uses iris pattern information, which has features of stability, security etc. Because of this reason, it is especially appropriate under certain circumstances of requiring a high security. Recently, using the iris information has a variety uses in the fields of access control and information security. In extracting the iris feature, it is desirable to extract the feature which is invariant to size, lights, rotation. We have easy solutions to the problem of iris size and lights by previous processing but there is still problem of iris feature extract invariant to rotation. In this paper, To improve an awareness ratio and decline in speed for a revision of rotation, it is proposed that the iris recognition method using Zernike Moment and Daubechies Wavelet. At first step, the proposed method groups rotated iris into similar things by statistical feature of Zernike Moment invariant to a rotation, which shortens processing time of iris recognition and looks equal to an established method in the performance of recognition too. therefore, proposed method could confirm the possibility of effective application for large scale iris recognition system.

A Study on the Automatic Inspection System using Invariant Moments Algorithm with the Change of Size and Rotation

  • Lee, Yong-Jung;Lee, Yang-Beom;Jeong, Gi-Hwa
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2004.05a
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    • pp.479-485
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    • 2004
  • The purpose of this study is to develop a practical image inspection system that could recognize it correctly, endowing flexibility to the productive field, although the same object for work will be changed in the size and rotated. In this experiment, it selected a fighter, rotating the direction from $30^{\circ}\;to\;45^{\circ}$ simultaneously while changing the size from 1/4 to 1/16, as an object inspection without using another hardware for exclusive image processing. The invariant moments, Hu has suggested, was used as feature vector moment descriptor. As a result of the experiment the image inspection system developed from this research was operated in real-time regardless of the chance of size and rotation for the object inspection, and it maintained the correspondent rates steadily above from 94% to 96%. Accordingly, it is considered as the flexibility can be considerably endowed to the factory automation when the image inspection system developed from this research is applied to the productive field.

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Comparison of invariant pattern recognition algorithms (불변 패턴인식 알고리즘의 비교연구)

  • 강대성
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.33B no.8
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    • pp.30-41
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    • 1996
  • This paper presents a comparative study of four pattern recognition algorithms which are invariant to translations, rotations, and scale changes of the input object; namely, object shape features (OSF), geometrica fourier mellin transform (GFMT), moment invariants (MI), and centered polar exponential transform (CPET). Pattern description is obviously one of the most important aspects of pattern recognition, which is useful to describe the object shape independently of translation, rotation, or size. We first discuss problems that arise in the conventional invariant pattern recognition algorithms, or size. We first discuss problems that arise in the coventional invariant pattern recognition algorithms, then we analyze their performance using the same criterion. Computer simulations with several distorted images show that the CPET algorithm yields better performance than the other ones.

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A Technique for Shape Features Extraction Using the Discrete Cosine Transform (이산 코사인 변환을 이용한 형태 특징 추출 기법)

  • Kim, Kyung-Su;Lee, Yung-Sin;Kim, Yong-Kuk;Lee, Yun-Bae;Kim, Pan-Ku
    • The Transactions of the Korea Information Processing Society
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    • v.5 no.5
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    • pp.1357-1366
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    • 1998
  • In this paper, we propose the method that extract shape features using the DCT(Discrete Cosine Transform) via simple invariant normalization. To retrieve effectively, we used measures, circularity and eccentricity, as filters to reduce the number of retrieved images. The experimental results show that our method is better than the methods of Fourier Descriptors and Moment Invariant for various leaf images.

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Estimation of Real Boundary with Subpixel Accuracy in Digital Imagery (디지털 영상에서 부화소 정밀도의 실제 경계 추정)

  • Kim, Tae-Hyeon;Moon, Young-Shik;Han, Chang-Soo
    • Journal of the Korean Society for Precision Engineering
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    • v.16 no.8
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    • pp.16-22
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    • 1999
  • In this paper, an efficient algorithm for estimating real edge locations to subpixel values is described. Digital images are acquired by projection into image plane and sampling process. However, most of real edge locations are lost in this process, which causes low measurement accuracy. For accurate measurement, we propose an algorithm which estimates the real boundary between two adjacent pixels in digital imagery, with subpixel accuracy. We first define 1D edge operator based on the moment invariant. To extend it to 2D data, the edge orientation of each pixel is estimated by the LSE(Least Squares Error)line/circle fitting of a set of pixels around edge boundary. Then, using the pixels along the line perpendicular to the estimated edge orientation the real boundary is calculated with subpixel accuracy. Experimental results using real images show that the proposed method is robust in local noise, while maintaining low measurement error.

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