• Title/Summary/Keyword: Zernike 모멘트

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A Study on the Invariant Recognition of Aircraft (항공기 불변 인식에 관한 연구)

  • 김창욱
    • Journal of the Korea Institute of Military Science and Technology
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    • v.3 no.2
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    • pp.88-100
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    • 2000
  • The design of an automatic aircraft recognition system involves two parts. The first part is extraction of invariant features independent of scale, rotation and translation. The second part is determination of optimal decision procedures, which are needed in the classification process. In this research, we extracted invariant aircraft features regardless of size, rotation and translation using Fourier Descriptors and Zernike Moments and classified using neural networks.

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Eye Detection Using Zernike Moments and SVM (Zernike 모멘트와 SVM을 이용한 눈 검출)

  • Kim, Hyoung-Joon;Baek, Yeul-Min;Kim, Whoi-Yul
    • Proceedings of the IEEK Conference
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    • 2007.07a
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    • pp.285-286
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    • 2007
  • This paper presents a method to detect eyes in the facial image using Zernike moments and SVM After detecting eye candidate regions from the facial image, Zernike moments are computed on those regions with moving a $15{\times}15$ window. Then, SVM that uses Zernike moments as an input vector detects eyes. In the experimental results, the proposed method shows the eye detection rate of about 90%.

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이동과 축척과 회전에 불변인 실용적인 패턴 인식 시스템

  • 김회율
    • The Magazine of the IEIE
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    • v.21 no.10
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    • pp.47-54
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    • 1994
  • 본 논문에서는 물체들의 이동(translation) 축적(scale) 그리고 회전방향(orientation)에 무관하게 물체를 인식하는 실용적인 패턴 인식 시스템을 소개한다. 이 시스템은 2진영상으로 변환하는데 필요한 임계치(threshold)의 큰 변화에도 덜 민감하다. 특징 벡터(feature vector)로 서는 Zernike 모멘트를 사용하였는데 지금까지 잘 알려진 Hu가 제안한 7개의 모멘트 불변수 (moment invariants)와 비교한다. 또한, 실용적인 기계 시각(machine vision) 시스템에 대해 세 가지 중요한 문제로서 패턴 정규화(pattern nomalization), Zernike 모멘트의 신속한 계산, 그리고 k-NN 규칙을 이용한 분류 등을 논의하였다. 실험에서는 임의의 회전 방향에서 문자들의 크기가 10x10 화소(pixel)에서 512x512 화소까지 변하는 서로 다른 크기를 가진 인쇄된 62개의 문자와 숫자 그리고 기호들을 서로 다른 임계치에서 인식하는 것을 보여준다.

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2-D Invariant Descriptors for Shape-Based Image Retrieval (모양에 기반한 영상 검색을 위한 2-D Invariant Descriptor)

  • 박종승;장덕호
    • Proceedings of the Korean Information Science Society Conference
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    • 1999.10b
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    • pp.554-556
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    • 1999
  • 모양 정보를 이용하는 내용기반 영상 검색 시스템에서 검색 정확도는 시스템에서 사용되는 모양 기술자에 매우 의존한다. 정확한 검색을 위해서 기술자는 이동, 회전, 스케일에 불변해야 한다. 본 논문에서는 모멘트 불변량과 푸리에 기술자를 복합적으로 사용하는 유사도 기법을 제시한다. 이 방법은 하나의 불변량 기술자를 사용하는 것보다 더 우수한 결과를 나타내었다. 푸리에 기술자와 네 개의 모멘트 불변량(Hu의 모멘트 불변량, Taubin의 모멘트 불변량, Flusser의 모멘트 불변량, Zernike 모멘트 불변량)을 구현하여 성능을 측정하였다. 영상분할된 이진 영상 데이터베이스로부터 각 기술자의 검색 정확도를 계산하였다. 실험 결과 경계선에 기초하는 푸리에 기술자와 영역에 기초하는 모멘트 불변량을 동시에 사용하는 방법이 영상 검색에 있어서 우수한 성능을 보였다.

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A Rotation Angle Estimation Method Based on Phase of ART (ART의 위상정보를 이용한 회전각도 추정 방법)

  • Lee, Jong-Min;Kim, Whoi-Yul
    • Journal of Broadcast Engineering
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    • v.17 no.1
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    • pp.81-94
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    • 2012
  • Several methods which utilize the phase of Zernike moments (ZMs) to estimate the rotation angle have shown good performance in terms of accuracy. In this paper, we provides the performance comparison results of the existing rotation angle estimation methods based on ZMs and propose an extension of Revaud et al.'s method [1] which utilizes the phase of ZMs; the proposed method uses angular radial transform coefficients instead of ZMs and yields better performance than the ZMs based methods in terms of accuracy. A set of ART can describe angular variation of image more intensively than ZMs, it enables more accurate estimation of the rotation angle than ZMs. In the experiments, the proposed method outperforms ZMs based method. Comparisons were made in terms of the root mean square error vs. the coverage on MPEG-7 shape dataset.

Real-time Sign Object Detection in Subway station using Rotation-invariant Zernike Moment (회전 불변 제르니케 모멘트를 이용한 실시간 지하철 기호 객체 검출)

  • Weon, Sun-Hee;Kim, Gye-Young;Choi, Hyung-Il
    • Journal of Digital Contents Society
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    • v.12 no.3
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    • pp.279-289
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    • 2011
  • The latest hardware and software techniques are combined to give safe walking guidance and convenient service of realtime walking assistance system for visually impaired person. This system consists of obstacle detection and perception, place recognition, and sign recognition for pedestrian can safely walking to arrive at their destination. In this paper, we exploit the sign object detection system in subway station for sign recognition that one of the important factors of walking assistance system. This paper suggest the adaptive feature map that can be robustly extract the sign object region from complexed environment with light and noise. And recognize a sign using fast zernike moment features which is invariant under translation, rotation and scale of object during walking. We considered three types of signs as arrow, restroom, and exit number and perform the training and recognizing steps through adaboost classifier. The experimental results prove that our method can be suitable and stable for real-time system through yields on the average 87.16% stable detection rate and 20 frame/sec of operation time for three types of signs in 5000 images of sign database.

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.

Performance Evaluation of Shape Descriptors for Gait Analysis Based on Silhouette Sequence (실루엣 영상기반 보행 분석을 위한 형태 기술자의 성능 평가)

  • Kim, Seon-Jong
    • Journal of Intelligence and Information Systems
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    • v.15 no.4
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    • pp.53-64
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    • 2009
  • This paper presents a performance evaluation of shape descriptors for gait analysis in case of silhouette sequence images. We used moment descriptors(MD), Fourier descriptors(FD) and Zernike descriptors(ZD) as a shape descriptor. To evaluate their performance, we firstly defined the performance index, that is, AI(asymmetry index) and PI(periodic index) based on the periodic property of the gait images. This is why they are represented by periodic parameters due to periodic gait images. This index means that how the shape is represented periodically. According to these indexes, we evaluated the data sets with periodic images, downloaded from internet. The results showed that Zernike descriptors had better performance of AI = 1.09 and PI = 2.21 than others. And in case of FD and ZD, it's efficient to implement the gait analysis with 5~10 parameters.

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Charactor Image Retrieval Using Color and Shape Information (컬러와 모양 정보를 이용한 캐릭터 이미지 검색)

  • 이동호;유광석;김회율
    • Journal of Broadcast Engineering
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    • v.5 no.1
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    • pp.50-60
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    • 2000
  • In this paper, we propose a new composite feature consists of both color and shape information that are suitable for the task of character image retrieval. This approach extracts shape-based information using Zernike moments from Y image in YCbCr color space. Zernike moments can extract shape-based features that are invariant to rotation, translation, and scaling. We also extract color-based information from the DCT coefficients of Cr and Cb image. This approach is good method reflecting human visual property and is suitable for web application such as large image database system and animation because higher retrieval rate has been achieved using only 36 features. In experiment, this method is applied to 3,834 character images. We confirmed that this approach brought about excellent effect by ANMRR(Average of Normalized, Modified Retrieval Rank), which is used in the evaluation measure of MPEG-7 color descriptor and BEP(Bull's Eye Performance), which is used in evaluation measure of shape descriptor in character image retrieval.

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Study on the Hand Gesture Recognition System and Algorithm based on Millimeter Wave Radar (밀리미터파 레이더 기반 손동작 인식 시스템 및 알고리즘에 관한 연구)

  • Lee, Youngseok
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.12 no.3
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    • pp.251-256
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    • 2019
  • In this paper we proposed system and algorithm to recognize hand gestures based on the millimeter wave that is in 65GHz bandwidth. The proposed system is composed of millimeter wave radar board, analog to data conversion and data capture board and notebook to perform gesture recognition algorithms. As feature vectors in proposed algorithm. we used global and local zernike moment descriptor which are robust to distort by rotation of scaling of 2D data. As Experimental result, performance of the proposed algorithm is evaluated and compared with those of algorithms using single global or local zernike descriptor as feature vectors. In analysis of confusion matrix of algorithms, the proposed algorithm shows the better performance in comparison of precision, accuracy and sensitivity, subsequently total performance index of our method is 95.6% comparing with another two mehods in 88.4% and 84%.