• Title/Summary/Keyword: 임펄스 잡음 검출기

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Impulse Noise Removal Using Noise Detector and Total Variation Optimization (잡음 검출기와 총변량 최적화를 이용한 영상의 임펄스 잡음제거)

  • Lee Im-Geun
    • The Journal of the Korea Contents Association
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    • v.6 no.4
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    • pp.11-18
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    • 2006
  • A new algorithm for removing salt and pepper impulse noise in image using impulse noise detector and total variation optimization is presented. The proposed two types of noise detectors which are based on the adaptive median filter, can detect impulse noise with high accuracy while reducing the probability of detecting image details as impulses. And the detectors maintain its performance independent of noise density. For removing impulses, total variation optimization is applied only to those detected noise candidate to reduces unnecessary computation. The proposed approach successfully remove impulse noise while preserving image details.

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Impulse Noise Removal using Past Tow Phase Algorithm (고속2단 알고리즘을 이용한 영상의 임펄스 잡음 제거)

  • Lee, Im-Geun;Han, Soo-Whan
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.11 no.1
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    • pp.95-101
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    • 2007
  • Recently, two phase scheme for removing impulse noise in images is proposed. This algorithms first detect the noise candidates based on the adaptive median filter, and then apply optimizing techniques recursively only to those noise candidates to restore image. Thus the noise detector with high accuracy is important role on this algorithm, In this paper, novel noise detector is proposed, which can detect impose noise with high accuracy while reducing the probability of false detecting image details as impulses. And the method for reducing computational cost of regularization phase is presented also.

A Study on Edge Detection Algorithm using Estimated Mask in Impulse Noise Environments (임펄스 잡음 환경에서 추정 마스크를 이용한 에지 검출 알고리즘에 관한 연구)

  • Lee, Chang-Young;Kim, Nam-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.9
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    • pp.2259-2264
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    • 2014
  • For edge detection methods, there are Sobel, Prewitt, Roberts and Canny edge detector, and these methods have insufficient detection characteristics in the image corrupted by the impulse noise. Therefore in this paper, in order to improve these disadvantages of the previous methods and to effectively detect the edge in the impulse noise environment, using the $5{\times}5$ mask, the noise factors within the $3{\times}3$ mask based on the central pixel is determined, and depending on its status, for noise-free it is processed as is, and if noise is found, by obtaining the estimated mask using the adjacent pixels of each factor, an algorithm that detects the edge is proposed.

Alpha-trimmed Mean Filter for Impulse Noise Removal (임펄스 잡음 제거를 위한 알파트림 평균 필터)

  • Kim, Kuk-Seung;Kim, Nam-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2010.05a
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    • pp.393-396
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    • 2010
  • In this paper the process of transmitting images signal restore to image corrupted by impulse noise proposed alpha-trimmed mean filter. the proposed filter first identifies the noise pixels using the morphological noise detector and then removes the detected impulse noise using the alpha-trimmed mean filter. these proposed filter can realize the accurate noise detection and it can remove impulse noise effectively while preserving edge region in the image very well. Through the simulation, we compared with the existing methods and capabilties.

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Adaptive Weighted Mean Filter to Remove Impulse Noise in Images (영상에서 임펄스 잡음제거를 위한 적응력 있는 가중 평균 필터)

  • Lee, Jun-Hee;Choi, Eo-Bin;Lee, Won-Yeol;Lim, Dong-Hoon
    • The Korean Journal of Applied Statistics
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    • v.21 no.2
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    • pp.233-245
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    • 2008
  • In this work, a new adaptive weighted mean filter is proposed for preserving image details while effectively suppressing impulse noise. The proposed filter is based on a noise pixel detection-estimation strategy. All the pixels are first detected using an impulse noise detector. Then the detected noise pixels are replaced with the output of the weighted mean filter over adaptive working window according to the rate of corrupted neighborhood pixels, while noise-free pixels are left unaltered. We compare the proposed filter to other existing filters in the qualitative measure and quantitative measures such as PSNR and MAE as well as computation time to verify the capability of the proposed filter. Extensive simulations show that the proposed filter performs better than other filters in impulse noise suppression and detail preservation without increasing of running time.

PSK Error Performance with Impulsive Noise and Cochannel Interference (임펄스 잡음 및 동일 채널 간섭하의 PSK신호의 오율 특성)

  • 강병옥;조성준
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.20 no.1
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    • pp.55-62
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    • 1983
  • The error rate performance of phase shift Keyed(PSK) signal has been evaluated in terms of carrier-to-noise ratio(CNR), carrier-to-interferer ratio(CIR), impulsive index, and the phase difference between signal and interferer in the environment of cochannel PSK inter-ference and impulsive noise. We hays derived a general equation of the probability density function (p.d.f.) of output of coherent phase detector. And the error rate of the received binary PSK(BPSK) signal has been numerically evaluated. The graphic results show us that the best case is the situation of the signal and the inter- ferer meet with orthogonal phase.

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Noise Eliminations by Median filtering in BDPCM Image (DBPCM에서 메디안 필터링에 의한 잡음 제거)

  • 황재정;이문호
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.18 no.8
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    • pp.1094-1101
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    • 1993
  • We show that image compression possibilities of BDPCM which reduces information and increases correlation with signal-blurring. Under the same quantization steps, signal flow at the coder is analyzed and complete signal reconstruction properties are shown. Dynamic range characteristics of the differences by the conventional DPCM predictor are analyzed. In order to improve the median filter reduces impulse noise with blurring, adaptive filtering for the differences is proposed. By means of the difference range, transmission impulse noises are detected and corrected by the filtering. Therefore, low bit rate image codec with noise eliminations is proposed.

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A Study on Edge Detection using Directional Mask in Impulse Noise Image (임펄스 잡음 영상에서 방향성 마스크를 이용한 에지 검출에 관한 연구)

  • Lee, Chang-Young;Kim, Nam-Ho
    • Journal of the Institute of Convergence Signal Processing
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    • v.15 no.4
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    • pp.135-140
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    • 2014
  • As the digital image devices are widely used, interests in the software- and the hardware-related image processing become higher and the image processing techniques are applied in various fields such as object recognition, object detection, fingerprint recognition, and etc. For the edge detections Sobel, Prewitt, Laplacian, Roberts and Canny detectors are used and these existing methods can excellently detect the edges of the images without noise. However, in the images corrupted by the impulse noise, these methods are insufficent in noise elimination characteristics, showing unsatisfactory edge detection. Therefore in this paper, in order to obtain excellent edge detection characteristics in the corrupted image by the impulse noise, an detection algorithm is porposed, which uses the central pixel of mask divided by four regions along the axis, calculates the estimated mask according to the representing pixel values in each regions, and detects the final edges by applying the estimates mask and the new directional one.

Design of Two Stage Amative Filters for Real time QRS Detection (실시간 ECG 분석을 위한 QRS 검출에 관한 연구 -2단 적응필터을 이용한-)

  • 이순혁;윤형로
    • Journal of Biomedical Engineering Research
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    • v.16 no.1
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    • pp.49-56
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    • 1995
  • This paper is a study on the design of adptive filter for QRS complex detection. We propose a simple adaptive algorithm to increase capability of noise cancelation in QRS complex detection with two stage adaptive filter. At the first stage, background noise is removed and at the next stage, only spectrum of QRS complex components is passed. Two adaptive filters can afford to keep track of the changes of both noise and QRS complex. Each adaptive filter consists of prediction error filter and FIR filter. The impulse response of FIR filter uses coefficients of prediction error filter. The detection rates for 105 and 108 of MIT/BIH data base were 99.3% and 97.4% respectively.

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