• Title/Summary/Keyword: preprocessing filter

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Morphological Filter for Enhancement of Monumental Inscription Image (금석문 영상 향상을 위한 형태학적 필터)

  • 김기석;최호형
    • Proceedings of the Korea Society for Industrial Systems Conference
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    • 2001.05a
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    • pp.311-317
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    • 2001
  • The study on Shilla monumental inscription has beer accomplished by many historians. However, the research on enhancement of monumental inscription image using digital image processing technique is not sufficient. The preprocessing using computer is needed fur accurate interpretation of history. In this paper, digital image enhancement algorithm based on mathematical morphology for noise reduction and character clearness is proposed. In the experiment, the subjective image quality is improved using the proposed algorithm.

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Translation- and Rotation-Invariant Fingerprint Authentication Based on Gabor Features (Gabor 특징에 기반한 이동 및 회전 불변 지문인증)

  • 김종화;조상현;성효경;최홍문
    • Proceedings of the IEEK Conference
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    • 2000.09a
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    • pp.901-904
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    • 2000
  • A direct authentication from gray-scale image, instead of the conventional multi-step preprocessing, is proposed using Gabor filter-based features from the gray-scale fingerprint around core point. The core point is located as a reference point for the translation invariant matching. And its principal symmetry axis is detected for the rotation invariant matching from its neighboring region centered at the core point. And then fingerprint is divided into non-overlapping blocks with respect to the core point and features are directly extracted form the blocked gray level fingerprint using Gabor filter. The proposed fingerprint authentication is based on the Euclidean distance between the corresponding Gabor features of the input and the template fingerprints. Experiments are conducted on 300${\times}$300 fingerprints obtained from a CMOS sensor with 500 dpi resolution, and the proposed method could lower the False Reject Rate(FRR) to 18.2% under False Acceptance Rate(FAR) of 0%.

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A Road Lane Detection Algorithm using HSI Color Information and ROI-LB (HSI 색정보와 관심영역(ROI-LB)을 이용한 차선검출 알고리듬)

  • Choi, In-Suk;Cheong, Cha-Keon
    • Proceedings of the IEEK Conference
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    • 2009.05a
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    • pp.222-224
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    • 2009
  • This paper presents an algorithm that extracts road lane's specific information by using HSI color information and performance enhancement of lane detection base on vision processing of drive assist. As a preprocessing for high speed lane detection, the optimal extraction of region of interest for lane boundary(ROI-LB) can be processed to reduction of detection region in which high speed processing is enabled and it also increases reliabilities by deleting edges those are misrecognized. Road lane is extracted with simultaneous processing of noise reduction and edge enhancement using the Laplacian filter, the reliability of feature extraction can be increased for various road lane patterns. Since noise can be removed by using saturation and brightness of HSI color model. Also it searches for the road lane's color information and extracts characteristics. The real road experimental results are presented to evaluate the effectiveness of the proposed method.

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An Implementation of Evolvable Adaptive Image Preprocessing Filter (진화적응성을 갖는 영상 전처리 필터 구현)

  • Lee, Seung-Young;Jun, In-Ja;Rhee, Phill-Kyu
    • Proceedings of the KIEE Conference
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    • 2002.07d
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    • pp.2783-2787
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    • 2002
  • 최근 멀티미디어 및 통신의 발달로 인하여 영상 정보를 이용한 응용시스템이 많이 연구되고있다. 중간 전달 매체를 이용한 응용시스템으로의 영상 정보를 전달과정에서 잡영(noise) 이 포함되어 시스템의 성능을 저하시키게 된다. 또한 잡영은 임의의 형태이기 때문에 상황에 따라 적합한 필터를 선택하기는 쉽지 않다. 본 논문에서는 유전자 알고리즘 프로세서를 이용하여 필터들의 구성 및 파라미터를 조절하여 임의의 잡영에 진화적응적인 능력을 가지는 영상 전처리 필터를 구현하였다. 주파수 영역의 잡영에 대해서는 하드웨어에 적합하고 구현이 용이한 멀티밴드필터(Multi-Band filter)를 설계하여 사용하였다. 시스템은 유전자알고리즘과 필터블록에 대해서는 하드웨어(FPCA)로 구현하였고 적합도 평가는 PC 기반으로 수행하였다. 실험결과 순수 PC기반의 시뮬레이션에 비해 속도향상 및 성능면에서도 만족할 만한 결과를 얻었다.

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The Study of Stereo Matching for 3D Image Implementation in Augmented Reality (증강현실에서 3D이미지 구현을 위한 스테레오 정합 연구)

  • Lee, Yonghwan;Kim, Youngseop;Park, Inho
    • Journal of the Semiconductor & Display Technology
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    • v.15 no.4
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    • pp.103-106
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    • 2016
  • 3D technology is main factor in Augmented Reality. Depth map is essential to make cubic effect using 2d image. There are a lot of ways to construct Depth map. Among them, stereo matching is mainly used. This paper presents how to generate depth map using stereo matching. For stereo matching, existing Dynamic programming method is used. To make accurate stereo matching, High-Boost Filter is applied to preprocessing method. As a result, when depth map is generated, accuracy based on Ground Truth soared.

Mobile measurement system of ECG signal in vehicle environment (차량운전자 심전도 신호의 QRS 검출 방법)

  • Park, Jae-Yong;Oh, Kwang-Seok;Lee, Choon-Young;Lee, Sang-Ryong
    • Proceedings of the IEEK Conference
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    • 2006.06a
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    • pp.895-896
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    • 2006
  • This paper proposes a new method to measure the ECG signal from the driver. The ECG signal is often measured in the room. But it is mixed with many kinds of noise when we measure it during the vehicle moving. We classified noise occupied most many parts as the experimental among them. And we designed one suitable filter for each noise. It used ALE(Adaptive Line Enhancement) to remove the noise occurred to electromagnetic wave in vehicle. To remove the noise occurred to steering or vibration of vehicle, we used Wavelet transformation after ALE(preprocessing filter).

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ECG Pattern Classification Using Back Propagation Neural Network (역전달 신경회로망을 이용한 심전도 신호의 패턴분류에 관한 연구)

  • 이제석;이정환;권혁제;이명호
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.30B no.6
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    • pp.67-75
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    • 1993
  • ECG pattern was classified using a back-propagation neural network. An improved feature extractor of ECG is proposed for better classification capability. It is consisted of preprocessing ECG signal by an FIR filter faster than conventional one by a factor of 5. QRS complex recognition by moving-window integration, and peak extraction by quadratic approximation. Since the FIR filter had a periodic frequency spectrum, only one-fifth of usual processing time was required. Also, segmentation of ECG signal followed by quadratic approximation of each segment enabled accurate detection of both P and T waves. When improtant features were extracted and fed into back-propagation neural network for pattern classification, the required number of nodes in hidden and input layers was reduced compared to using raw data as an input, also reducing the necessary time for study. Accurate pattern classification was possible by an appropriate feature selection.

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Mode-by-mode evaluation of structural systems using a bandpass-HHT filtering approach

  • Lin, Jeng-Wen
    • Structural Engineering and Mechanics
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    • v.36 no.6
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    • pp.697-714
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    • 2010
  • This paper presents an improved version of the Hilbert-Huang transform (HHT) for the modal evaluation of structural systems or signals. In this improved HHT, a well-designed bandpass filter is used as preprocessing to separate and determine each mode of the signal for solving the inherent modemixing problem in HHT (i.e., empirical mode decomposition, EMD, associated with the Hilbert transform). A screening process is then applied to remove undesired intrinsic mode functions (IMFs) derived from the EMD of the signal's mode. A "best" IMF is selected in each screening process that utilizes the orthogonalization coefficient between the signal's mode and its IMFs. Through mode-by-mode signal filtering, parameters such as the modal frequency can be evaluated accurately when compared to the theoretical value. Time history of the identified modal frequency is available. Numerical results prove the efficiency of the proposed approach, showing relative errors 1.40%, 2.06%, and 1.46%, respectively, for the test cases of a benchmark structure in the lab, a simulated time-varying structural system, and of a linear superimposed cosine waves.

Feature Selection for Anomaly Detection Based on Genetic Algorithm (유전 알고리즘 기반의 비정상 행위 탐지를 위한 특징선택)

  • Seo, Jae-Hyun
    • Journal of the Korea Convergence Society
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    • v.9 no.7
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    • pp.1-7
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    • 2018
  • Feature selection, one of data preprocessing techniques, is one of major research areas in many applications dealing with large dataset. It has been used in pattern recognition, machine learning and data mining, and is now widely applied in a variety of fields such as text classification, image retrieval, intrusion detection and genome analysis. The proposed method is based on a genetic algorithm which is one of meta-heuristic algorithms. There are two methods of finding feature subsets: a filter method and a wrapper method. In this study, we use a wrapper method, which evaluates feature subsets using a real classifier, to find an optimal feature subset. The training dataset used in the experiment has a severe class imbalance and it is difficult to improve classification performance for rare classes. After preprocessing the training dataset with SMOTE, we select features and evaluate them with various machine learning algorithms.

Detecting the Prostate Contour in TRUS Image using Support Vector Machine and Rotation-invariant Textures (SVM과 회전 불변 텍스처 특징을 이용한 TRUS 영상의 전립선 윤곽선 검출)

  • Park, Jae Heung;Seo, Yeong Geon
    • Journal of Digital Contents Society
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    • v.15 no.6
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    • pp.675-682
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    • 2014
  • Prostate is only an organ of men. To diagnose the disease of the prostate, generally transrectal ultrasound(TRUS) images are used. Detecting its boundary is a challenging and difficult task due to weak prostate boundaries, speckle noise and the short range of gray levels. In this paper a method for automatic prostate segmentation in TRUS images using Support Vector Machine(SVM) is presented. This method involves preprocessing, extracting Gabor feature, training, and prostate segmentation. The speckle reduction for preprocessing step has been achieved by using stick filter and top-hat transform has been implemented for smoothing. Gabor filter bank for extraction of rotation-invariant texture features has been implemented. SVM for training step has been used to get each feature of prostate and nonprostate. Finally, the boundary of prostate is extracted. A number of experiments are conducted to validate this method and results shows that the proposed algorithm extracted the prostate boundary with less than 10% relative to boundary provided manually by doctors.