• 제목/요약/키워드: Image analysis statistics

검색결과 328건 처리시간 0.03초

Feature Extraction and Statistical Pattern Recognition for Image Data using Wavelet Decomposition

  • Kim, Min-Soo;Baek, Jang-Sun
    • Communications for Statistical Applications and Methods
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    • 제6권3호
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    • pp.831-842
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    • 1999
  • We propose a wavelet decomposition feature extraction method for the hand-written character recognition. Comparing the recognition rates of which methods with original image features and with selected features by the wavelet decomposition we study the characteristics of the proposed method. LDA(Linear Discriminant Analysis) QDA(Quadratic Discriminant Analysis) RDA(Regularized Discriminant Analysis) and NN(Neural network) are used for the calculation of recognition rates. 6000 hand-written numerals from CENPARMI at Concordia University are used for the experiment. We found that the set of significantly selected wavelet decomposed features generates higher recognition rate than the original image features.

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How to identify fake images? : Multiscale methods vs. Sherlock Holmes

  • Park, Minsu;Park, Minjeong;Kim, Donghoh;Lee, Hajeong;Oh, Hee-Seok
    • Communications for Statistical Applications and Methods
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    • 제28권6호
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    • pp.583-594
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    • 2021
  • In this paper, we propose wavelet-based procedures to identify the difference between images, including portraits and handwriting. The proposed methods are based on a novel combination of multiscale methods with a regularization technique. The multiscale method extracts the local characteristics of an image, and the distinct features are obtained through the regularized regression of the local characteristics. The regularized regression approach copes with the high-dimensional problem to build the relation between the local characteristics. Lytle and Yang (2006) introduced the detection method of forged handwriting via wavelets and summary statistics. We expand the scope of their method to the general image and significantly improve the results. We demonstrate the promising empirical evidence of the proposed method through various experiments.

정지장면의 연속 프레임 영상 간 통계에 기반한 영상분할 (Image Segmentation based on Statistics of Sequential Frame Imagery of a Static Scene)

  • 서수영;고인철
    • Spatial Information Research
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    • 제18권3호
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    • pp.73-83
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    • 2010
  • 본 연구는 정지장면의 연속영상간 각 픽셀위치에서 일어나는 통계적 특성을 활용하여 영상을 분할하는 기법을 제안한다. 공간정보의 획득과 분석에서 디지털 영상 처리 기법의 활용은 아주 중요한 의미를 가진다. 특히 디지털 영상의 영역 구분을 위해 다양한 영상 분할(image segmentation) 기법들이 활용되고 있다. 본 연구에서는 선행 연구한 연속프레임 영상의 분광학적 특성 분석의 결과를 바탕으로 연속 프레임 간 Randomness를 활용한 이미지 분할 방법을 제안하였다. 우선 연속 프레임 간 각 화소에 통계학적인 분석 방법을 적용하여 각 화소의 평균과 표준편차 값을 구하고, 이를 통하여 대상 영상에서 가장 신뢰할 만한 화소들을 찾아 씨앗 점(seed point)을 결정하였다. 그리고 이 씨앗 점들을 시작으로 이웃 화소 간 T-test를 실시하였으며, 이를 기반으로 영역 성장(region growing)의 개념을 적용하여 영상을 분할 할 수 있는 기법을 연구하였다. 제안방식의 성능을 검증하기 위하여 실험을 통하여 기존의 방식과 비교분석을 수행하였다. 이러한 실험의 결과 영상분할에서 영상의 단일 프레임을 활용한 것보다 연속 프레임을 활용한 경우가 유리함을 확인 할 수 있었다.

CONSTRAINING COSMOLOGICAL PARAMETERS WITH IMAGE SEPARATION STATISTICS OF GRAVITATIONALLY LENSED SDSS QUASARS: MEAN IMAGE SEPARATION AND LIKELIHOOD INCORPORATING LENS GALAXY BRIGHTNESS

  • Han, Du-Hwan;Park, Myeong-Gu
    • 천문학회지
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    • 제48권1호
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    • pp.83-92
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    • 2015
  • Recent large scale surveys such as Sloan Digital Sky Survey have produced homogeneous samples of multiple-image gravitationally lensed quasars with well-defined selection effects. Statistical analysis on these can yield independent constraints on cosmological parameters. Here we use the image separation statistics of lensed quasars from Sloan Digital Sky Survey Quasar Lens Search (SQLS) to derive constraints on cosmological parameters. Our analysis does not require knowledge of the magnification bias, which can only be estimated from the detailed knowledge on the quasar luminosity function at all redshifts, and includes the consideration for the bias against small image separation quasars due to selection against faint lens galaxy in the follow-up observations for confirmation. We first use the mean image separation of the lensed quasars as a function of redshift to find that cosmological models with extreme curvature are inconsistent with observed lensed quasars. We then apply the maximum likelihood test to the statistical sample of 16 lensed quasars that have both measured redshift and magnitude of lens galaxy. The likelihood incorporates the probability that the observed image separation is realized given the luminosity of the lens galaxy in the same manner as Im et al. (1997). We find that the 95% confidence range for the cosmological constant (i.e., the vacuum energy density) is $0.72{\leq}{\Omega}_{\Lambda}{\leq}1.0$ for a flat universe. We also find that the equation of state parameter can be consistent with -1 as long as the matter density ${\Omega}_m{\leq}0.4$ (95% confidence range). We conclude that the image separation statistics incorporating the brightness of lens galaxies can provide robust constraints on the cosmological parameters.

이미지 데이터를 모니터링하는 관리도에서 이미지와 ROI 크기 조정의 영향 (Resizing effect of image and ROI in using control charts to monitor image data)

  • 이주형;윤형욱;이성민;이재헌
    • 응용통계연구
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    • 제30권3호
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    • pp.487-501
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    • 2017
  • 최근 산업의 생산공정에서는 머신비전시스템을 통하여 제품의 품질특성치에 대한 정보를 이미지 데이터로 제공하는 경우가 많다. 따라서 산업과 의학 현장에서 이미지 데이터의 모니터링을 위해 관리도 절차의 필요성이 많이 대두되고 있다. 이미지 데이터를 모니터링하는 관리도 절차는 전통적으로 사용하는 관리도 절차와 유사한 점도 있지만, 데이터의 구조를 비롯하여 각 이미지에서 ROI를 설정하여 관리도 절차를 적용하는 등 서로 다른 점도 많이 있다. 이 논문에서는 생산공정에서 제공되는 이미지 데이터에 대해 관리도를 사용하는 절차를 소개하고, 이미지 또는 ROI 크기의 확대와 축소가 제품의 이상원인을 탐지하는데 어떠한 영향이 주는지를 모의실험을 통하여 알아보았고 각 관리도의 성능 또한 비교하였다.

Digital Image Comparisons for Investigating Aging Effects and Artificial Modifications Using Image Analysis Software

  • Yoo, Yeongsik;Yoo, Woo Sik
    • 보존과학회지
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    • 제37권1호
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    • pp.1-12
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    • 2021
  • In the digital era, large archives of information and Internet accessibility make information search, including image search, easier and affordable, even from remote locations. Information transmission and sharing can be performed instantly, at any moment. In the case of images, there are risks of transmitting and recklessly sharing intentionally modified images. Such modified images can also be transmitted and used as an additional source of information by followers. In this study, historical portraits of Yu Kil-Chun are shown, who was the first Korean student to study in both Japan and the United States. He was an intellectual, writer, politician, and independence activist of Korea's late Joseon Dynasty. Using image processing software, the portrait images were compared to investigate aging effects and artificial modifications. Statistics of red (R), green (G), blue (B), and L*, a*, and b* values of every pixel in the selected identical areas of the portraits were compared to identify possible causes of variations, including aging effects and artificial modifications. Sepia toning, used in black and white photographs until the 1930s, and modern digital sepia toning can be very confusing owing to their aging effects. The importance of preservation of physical copies and preservation of context (interconnections between data and between documents) is discussed from archiving and conservation science perspectives.

A Cross-cultural study of Body Image Perceptions between Korean and British University Students

  • Kim, Bu-Yong;Lee, Seunghee
    • 패션비즈니스
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    • 제19권6호
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    • pp.14-27
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    • 2015
  • This study explores the comparison of body image, body satisfaction, and clothing behaviors between Korean and British young women. Body image was measured by two methods: visual and verbal. For the data analysis, the Statistical Package for Social Science (SPSS) Version 16.0 for Windows was used to provide descriptive statistics, an independent sample t-test, and paired sample t- tests were applied in this study. Our results show that Korean and British female college students perceived ideal-body images that were smaller than their self defined body images. The ideal and self-images were significantly different in both groups. Both groups were dissatisfied with their own body size. The study was limited to a small sample size. Future studies using more participants from a more diverse age group and ethnic groups are recommended. The study will help marketers and retailers develop new products and new markets aimed at Korean and British women related to body image and body satisfaction.

문서 영상의 그림 영역에서 통계적 분석을 이용한 단어 영상 추출 (Word Image Decomposition from Image Regions in Document Images using Statistical Analyses)

  • 정창부;김수형
    • 정보처리학회논문지B
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    • 제13B권6호
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    • pp.591-600
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    • 2006
  • 본 논문에서는 문서 영상의 그림 영역에서 통계적 분석을 통한 단어 영상을 추출하는 방법을 제안한다. 제안 방법은 그림 영역의 구성 요소를 문자 성분과 그래픽 성분으로 분류하기 위하여 연결요소에 대한여 통계적 분석 방법인 상자그림 분석을 적용하고, 분류된 문자 성분들에 대하여 지역적 밀집도를 분석하여 문자 영역을 추출한다. 추출된 문자 영역에서 투영 히스토그램 분석을 통하여 문자열을 추출하고, 문자열을 단어단위 영상으로 분리하기 위하여 투영 히스토그램 분석과 갭 군집화, 특수 기호 검출 등을 수행한다. 제안 방법은 임계값의 사용 대신에 그림 영역의 구성 요소들에 대하여 통계적 분석을 수행하기 때문에 그림의 형태 변화에 민감하지 않으며, 지역적 밀집도 분석으로 보다 정확한 문자 영역을 추출하였다. 또한 제안 방법의 응용 분야인 주제어 검색을 위한 오프라인의 전처리에 해당하는 문서 영상의 단어단위 영상 추출에 적용하여 제안 방법에 대한 연구의 필요성을 제시하였다.

신경회로망 ICA를 이용한 혼합영상신호의 분리 (Blind Image Separation with Neural Learning Based on Information Theory and Higher-order Statistics)

  • 조현철;이권순
    • 전기학회논문지
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    • 제57권8호
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    • pp.1454-1463
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    • 2008
  • Blind source separation by independent component analysis (ICA) has applied in signal processing, telecommunication, and image processing to recover unknown original source signals from mutually independent observation signals. Neural networks are learned to estimate the original signals by unsupervised learning algorithm. Because the outputs of the neural networks which yield original source signals are mutually independent, then mutual information is zero. This is equivalent to minimizing the Kullback-Leibler convergence between probability density function and the corresponding factorial distribution of the output in neural networks. In this paper, we present a learning algorithm using information theory and higher order statistics to solve problem of blind source separation. For computer simulation two deterministic signals and a Gaussian noise are used as original source signals. We also test the proposed algorithm by applying it to several discrete images.

여고생들의 라이프스타일과 상표 및 광고 이미지 지각에 관한 연구 (A study on the Life Style and the Perception of brand Image and Advertisement Image of Adolescents)

  • 차은정;박혜선
    • 한국의류학회지
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    • 제23권8호
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    • pp.1119-1130
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    • 1999
  • The purpose of this was to investigate the differences in recognition of brand and advertisement image according to the life style segments of adolescents. The subjects selected for the final analysis were 613 female high school students whoe were residents in Seoul Pusan and Taejeon. The statistics used for data analysis were factor analysis one-way ANOVA Duncan's multiple range test paired t-test frequency distribution and percentage by the SPSS program The results of this study were as follows : 1. The life style of adolescents wee classified into five groups : Sports Uninterest group Friend Preference/Fashion Uninterest group Sports Preference/Home Oriented group Fashion Interest group and Confidence group. 2, The brand image and advertisement image recognition didn's correspond in general 3. The brand image and advertisement image recognition were significantly different among five groups of life style. The Confidence group and Friend Preference/ Fashion Uninterest group recognized brand image and advertisement image lower than the other groups.

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