• Title/Summary/Keyword: Haar function

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Multiresolution Model for Vector Fields Defined over Curvilinear Grids (곡선 그리드상에 정의된 벡터 필드를 위한 다해상도 모형)

  • 정일홍;장우현;조세홍;이봉환
    • Journal of Korea Multimedia Society
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    • v.3 no.5
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    • pp.542-549
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    • 2000
  • This Paper presents the development of multiresolution model for the analysis and visualization of two-dimensional flows over curvilinear grids. Multiresolution analysis provides a useful and efficient tool to represent shape and to analyze features at multiple level of detail. Applying multiresolution analysis to vector field visualization is very useful and powerful as the vector field's data sets are usually huge and complex. Using approximation at lower resolution, brief outline of topology can be extracted in short periods of time. Local reconstruction allows the user to zoom in or out, only by reconstructing the portion of interest. This new model is based upon nested spaces of piecewise defined function over nested curvilinear grid domains. The nested domains are selected so as to maintain the original geometry of the inner boundary. This paper presents the refinement and decomposition equations for Haar wavelet over these domains and shows some examples.

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Asymptotic Performance of MIMO-MC-CDMA Systems in Multi-cell Environments (다중셀 환경에서 MIMO-MC-CDMA시스템의 점근적 성능)

  • Kim, Kyeong-Yeon;Ham, Jae-Sang;Lee, Chung-Yong
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.44 no.7 s.361
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    • pp.47-52
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    • 2007
  • This paper analyzes the output signal-to-interference-plus-noise ratio (SINR) for a multiple-input-multiple-output (MIMO) multicarrier code division multiple access (MC-CDMA) system with minium mean square error receivers in multi-cell environments. A previous work in single cell environments is extended into analysis in multi-cell environments. The use of Haar unitary code matrix for asymptotic analysis causes other cell interferences expressed with a diagonal matrix haying different diagonal values. This paper shows that other cell interferences converge to an identity matrix whose gain is expressed by only other cell interference power in mean square sense and finds asymptotic deterministic SINRs for a given other cell interference. Under the assumption that the sum of lognormal fading components is distributed by other lognormal function, we show the comparison between theoretical performances and simulations from the view point of bit error rate and present average throughput performance according to the cell radius.

Time-Frequency Analysis Using Linear Combination Wavelet Transform and Its Application to Diagnostic Monitoring System (선형조합 웨이브릿 변환을 사용한 시간-주파수 분석 및 진단 모니터링 시스템의 적용)

  • 김민수;권기룡;김석태
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.3 no.1
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    • pp.83-95
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    • 1999
  • Wavelet transform has localization for time or frequency. It is useful to analyze a nonstationary signal. Basic function on wavelet transform is generated dilating and translating the original wavelet(mother wavelet). In this paper, time-frequency analysis method using linear combination wavelet transform is proposed. And it is applied to diagnostic monitoring system using the proposed linear combination wavelet transform. The stationary and nonstationary signal is used linear chirp signal, fan noise signal, a sinusoid signal from revolution body, electronic signal. Transform applied to signal analysis use fast Fourier transform (FFT), Daubechies, Haar and proposed linear combination method. The result of time-frequency analysis using linear combination wavelet transform is suited for portraying nonstationary time signal as well as stationary signal. Also the diagnostic monitoring system carry out the effective the signal analysis.

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A Study on the Analysis and State Estimation of Bilinear Systems via Orthogonal Functions (직교함수에 의한 쌍일차계의 해석 및 상태 추정에 관한 연구)

  • 안두수;신재선
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.39 no.6
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    • pp.598-606
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    • 1990
  • Common problems encountered when orthogonal functions are used in system analysis and state estimation are the time consuming process of high order matrix inversion required in finding the Kronecker products and the truncation errors. In this paper, therefore, a method for the analysis of bilinear systems using Walsh, Block pulse, and Haar functions is devised, Then, state estimation of bilinear system is also studied based on single term expansion of orthogonal functions. From the method presented here, when compared to the other conventional methods, we can obtain the results with simpler computation as the number of interval increases, and the results approach the original function faster even at randomly chosen points regardless of the definition of intervals. In addition, this method requires neither the inversion of large matrices on obtaining the expansion coefficients nor the cumbersome procedures in finding Kronecker products. Thus, both the computing time and required memory size can be significantly reduced.

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A Study on Illumination Mechanism of Steel Plate Inspection Using Wavelet Synthetic Images (이산 웨이블릿 합성 영상을 이용한 철강 후판 검사의 조명 메커니즘에 관한 연구)

  • Cho, Eun Deok;Kim, Gyung Bum
    • Journal of the Semiconductor & Display Technology
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    • v.17 no.2
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    • pp.26-31
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    • 2018
  • In this paper, surface defects and typical illumination mechanisms for steel plates are analyzed, and then optimum illumination mechanism is selected using discrete wavelet transform (DWT) synthetic images and discriminant measure (DM). The DWT synthetic images are generated using component images decomposed by Haar wavelet transform filter. The best synthetic image according to surface defects is determined using signal to noise ratio (SNR). The optimum illumination mechanism is selected by applying discriminant measure (DM) to the best synthetic images. The DM is applied using the tenengrad-euclidian function. The DM is evaluated as the degree of contrast using the defect boundary information. The performance of the optimum illumination mechanism is verified by quantitative data and intuitive image looks.

A Classification of Breast Tumor Tissue Images Using SVM (SVM을 이용한 유방 종양 조직 영상의 분류)

  • Hwang, Hae-Gil;Choi, Hyun-Ju;Yoon, Hye-Kyoung;Choi, Heung-Kook
    • Proceedings of the Korea Institute of Convergence Signal Processing
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    • 2005.11a
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    • pp.178-181
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    • 2005
  • Support vector machines is a powerful learning algorithm and attempt to separate belonging to two given sets in N-dimensional real space by a nonlinear surface, often only implicitly dened by a kernel function. We described breast tissue images analyses using texture features from Haar wavelet transformed images to classify breast lesion of ductal organ Benign, DCIS and CA. The approach for creating a classifier is composed of 2 steps: feature extraction and classification. Therefore, in the feature extraction step, we extracted texture features from wavelet transformed images with $10{\times}$ magnification. In the classification step, we created four classifiers from each image of extracted features using SVM(Support Vector Machines). In this study, we conclude that the best classifier in histological sections of breast tissue in the texture features from second-level wavelet transformed images used in Polynomial function.

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Region-Based Facial Expression Recognition in Still Images

  • Nagi, Gawed M.;Rahmat, Rahmita O.K.;Khalid, Fatimah;Taufik, Muhamad
    • Journal of Information Processing Systems
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    • v.9 no.1
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    • pp.173-188
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    • 2013
  • In Facial Expression Recognition Systems (FERS), only particular regions of the face are utilized for discrimination. The areas of the eyes, eyebrows, nose, and mouth are the most important features in any FERS. Applying facial features descriptors such as the local binary pattern (LBP) on such areas results in an effective and efficient FERS. In this paper, we propose an automatic facial expression recognition system. Unlike other systems, it detects and extracts the informative and discriminant regions of the face (i.e., eyes, nose, and mouth areas) using Haar-feature based cascade classifiers and these region-based features are stored into separate image files as a preprocessing step. Then, LBP is applied to these image files for facial texture representation and a feature-vector per subject is obtained by concatenating the resulting LBP histograms of the decomposed region-based features. The one-vs.-rest SVM, which is a popular multi-classification method, is employed with the Radial Basis Function (RBF) for facial expression classification. Experimental results show that this approach yields good performance for both frontal and near-frontal facial images in terms of accuracy and time complexity. Cohn-Kanade and JAFFE, which are benchmark facial expression datasets, are used to evaluate this approach.

High Speed Face and Eye Detection Algorithm for Personal 3D Broadcasting Devices with User Interactive Function (사용자 인터페이스 기능의 개인용 3D 방송단말을 위한 얼굴 및 눈인식 알고리즘의 고속 검출 방법)

  • Song, Hyok;Kwak, Soo-Yeong;Bae, Jin-Woo;Choi, Byeong-Ho
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2011.07a
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    • pp.428-429
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    • 2011
  • 3D 디스플레이 장치는 디스플레이 장치의 시점 수에 따라 다시점 디스플레이 장치 및 스테레오 디스플레이 장치로 구분할 수 있다. 스테레오 디스플레이 장치는 좌우 두 개의 영상을 디스플레이 방식에 따라 영상포맷을 변경하여 디스플레이에 보여지고 다시점 디스플레이는 두 개 이상의 영상 데이터를 포함하는 것으로 구분할 수 있다. 영상의 화질문제로 인하여 최근 3DTV는 스테레오 방식을 사용하고 있으며 대기업에서 양산하고 있는 기술이다. 스테레오 방식에서는 개인용 단말의 경우 사용자의 위치 및 눈의 위치에 따라 깊이감을 달리 보여주는 장치가 개발되고 있어 이에 대한 연구를 진행하였다. 이와같은 기술의 흐름에 맞춰 3D 디스플레이 장치를 위한 눈 추적 알고리즘을 구현하였다. 본 논문에는 카메라에서 입력되는 영상에서 얼굴영역을 Haar training 방법을 통하여 추출하였으며 PCA 방법을 통하여 눈 영역을 추출하였다. 알고리즘의 복잡도로 인하여 연산량을 줄이기 위하여 Downsampling 방법을 활용하여 연산량을 약 26% 감소시켰다. 본 연구 결과를 통하여 얼굴 및 눈 추적 알고리즘 구현시 최적화를 위하여 필요한 프로세스를 예측할 수 있다.

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The Facial Area Extraction Using Multi-Channel Skin Color Model and The Facial Recognition Using Efficient Feature Vectors (Multi-Channel 피부색 모델을 이용한 얼굴영역추출과 효율적인 특징벡터를 이용한 얼굴 인식)

  • Choi Gwang-Mi;Kim Hyeong-Gyun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.9 no.7
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    • pp.1513-1517
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    • 2005
  • In this paper, I make use of a Multi-Channel skin color model with Hue, Cb, Cg using Red, Blue, Green channel altogether which remove bight component as being consider the characteristics of skin color to do modeling more effective to a facial skin color for extracting a facial area. 1 used efficient HOLA(Higher order local autocorrelation function) using 26 feature vectors to obtain both feature vectors of a facial area and the edge image extraction using Harr wavelet in image which split a facial area. Calculated feature vectors are used of date for the facial recognition through learning of neural network It demonstrate improvement in both the recognition rate and speed by proposed algorithm through simulation.

Steganalysis Based on Image Decomposition for Stego Noise Expansion and Co-occurrence Probability (스테고 잡음 확대를 위한 영상 분해와 동시 발생 확률에 기반한 스테그분석)

  • Park, Tae-Hee;Kim, Jae-Ho;Eom, Il-Kyu
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.49 no.2
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    • pp.94-101
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    • 2012
  • This paper proposes an improved image steganalysis scheme to raise the detection rate of stego images out of cover images. To improve the detection rate of stego image in the steganalysis, tiny variation caused by data hiding should be amplified. For this, we extract feature vectors of cover image and stego image by two steps. First, we separate image into upper 4 bit subimage and lower 4 bit subimage. As a result, stego noise is expanded more than two times. We decompose separated subimages into twelve subbands by applying 3-level Haar wavelet transform and calculate co-occurrence probabilities of two different subbands in the same scale. Since co-occurrence probability of the two wavelet subbands is affected by data hiding, it can be used as a feature to differentiate cover images and stego images. The extracted feature vectors are used as the input to the multilayer perceptron(MLP) classifier to distinguish between cover and stego images. We test the performance of the proposed scheme over various embedding rates by the LSB, S-tool, COX's SS, and F5 embedding method. The proposed scheme outperforms the previous schemes in detection rate to existence of hidden message as well as exactness of discrimination.