• Title/Summary/Keyword: Noise removal

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High Density Salt and Pepper Noise Removal using Interpolation (보간법을 이용한 고밀도 Salt and Pepper 잡음 제거)

  • Baek, Ji-Hyeon;Park, Jun-Mo;Kim, Nam-Ho
    • Journal of the Institute of Convergence Signal Processing
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    • v.20 no.3
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    • pp.165-170
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    • 2019
  • Recently, modern society has come up with the importance of video processing as various imaging systems have developed. However, deterioration occurs in the process of transmitting, processing, and storing video data for various reasons. Deterioration will damage the original image, and the typical noise is Salt and Pepper noise. There are A-TMF, CWMF, and linear interpolation as the means to eliminate Salt and Pepper noise. However, these methods show somewhat poor noise abatement performance in high-density noise areas. Therefore, this paper proposes an algorithm to eliminate noise using modified linear interpolation. To prove the validity of the proposed algorithm, PSNR, Profile was used to compare it with existing methods.

Denoising Traditional Architectural Drawings with Image Generation and Supervised Learning (이미지 생성 및 지도학습을 통한 전통 건축 도면 노이즈 제거)

  • Choi, Nakkwan;Lee, Yongsik;Lee, Seungjae;Yang, Seungjoon
    • Journal of architectural history
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    • v.31 no.1
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    • pp.41-50
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    • 2022
  • Traditional wooden buildings deform over time and are vulnerable to fire or earthquakes. Therefore, traditional wooden buildings require continuous management and repair, and securing architectural drawings is essential for repair and restoration. Unlike modernized CAD drawings, traditional wooden building drawings scan and store hand-drawn drawings, and in this process, many noise is included due to damage to the drawing itself. These drawings are digitized, but their utilization is poor due to noise. Difficulties in systematic management of traditional wooden buildings are increasing. Noise removal by existing algorithms has limited drawings that can be applied according to noise characteristics and the performance is not uniform. This study presents deep artificial neural network based noised reduction for architectural drawings. Front/side elevation drawings, floor plans, detail drawings of Korean wooden treasure buildings were considered. First, the noise properties of the architectural drawings were learned with both a cycle generative model and heuristic image fusion methods. Consequently, a noise reduction network was trained through supervised learning using training sets prepared using the noise models. The proposed method provided effective removal of noise without deteriorating fine lines in the architectural drawings and it showed good performance for various noise types.

Sharpness-aware Evaluation Methodology for Haze-removal Processing in Automotive Systems

  • Hwang, Seokha;Lee, Youngjoo
    • IEIE Transactions on Smart Processing and Computing
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    • v.5 no.6
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    • pp.390-394
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    • 2016
  • This paper presents a new comparison method for haze-removal algorithms in next-generation automotive systems. Compared to previous peak signal-to-noise ratio-based comparisons, which measure similarity, the proposed modulation transfer function-based method checks sharpness to select a more suitable haze-removal algorithm for lane detection. Among the practical filtering schemes used for a haze-removal algorithm, experimental results show that Gaussian filtering effectively preserves the sharpness of road images, enhancing lane detection accuracy.

A Study on Mixed Noise Removal Algorithm based on Wavelet (웨이브렛 기반의 혼합된 잡음제거 알고리즘에 관한 연구)

  • Kim, Nam-Ho;Bae, Sang-Bum
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2007.06a
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    • pp.739-742
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    • 2007
  • In the step processing multimedia information signals transmitted by a variety of mediums, noises are generated by the internal or exterior causes of systems and these noises degrade the perception about information signals. Therefore, in order to remove noises and restore signals a great number of researches have been progressed and recently, many noise removal methods using time-frequency localization of wavelet have been applied in wide applications. Moreover, when two wavelet bases are designed to accomplish the Hilbert transform pair, wavelet can be efficiently applied to detect characteristics of signals. Therefore, in this paper, in order to restore the corrupted signal by noises, a noise removal algorithm using the Hilbert transform pair of wavelet was proposed.

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A Study on Noise Removal Using Over-sampled Discrete Wavelet Transforms (과표본화 이산 웨이브렛 변환의 잡음제거에 관한 연구)

  • Jee, Innho
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.19 no.1
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    • pp.69-75
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    • 2019
  • The standard application area of over-sampled discrete wavelet transform is noise removal technology for digital images. Comparing dual density discrete wavelet transform with dual tree discrete wavelet transform, we have almost similar characteristics. In this paper, several discrete wavelet transforms are accomplished on digital image existing with noise, noises are removed with threshold processing algorithm on subband, performance evaluation experiments of the reconstructed images are accomplished. If we decide appropriate threshold value, the effect noise removal is possible. In this paper, we can certified that the suggested algorithm of 3-direction separable processing with 2 dimension dual density discrete wavelet transform is superior to several experiment results.

MRF-based Adaptive Noise Detection Algorithm for Image Restoration (영상 복원을 위한 MRF 기반 적응적 노이즈 탐지 알고리즘)

  • Nguyen, Tuan-Anh;Hong, Min-Cheol
    • Journal of Korea Multimedia Society
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    • v.16 no.12
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    • pp.1368-1375
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    • 2013
  • In this paper, we presents a spatially adaptive noise detection and removal algorithm. Under the assumption that an observed image and the additive noise have Gaussian distribution, the noise parameters are estimated with local statistics, and the parameters are used to define the constraints on the noise detection process, where the first order Markov Random Field (MRF) is used. In addition, an adaptive low-pass filter having a variable window sizes defined by the constraints on noise detection is used to control the degree of smoothness of the reconstructed image. Experimental results demonstrate the capability of the proposed algorithm.

A Study on Composite Filters for Salt and Pepper Noise Removal (Salt and Pepper 잡음 제거를 위한 복합 필터에 관한 연구)

  • Hong, Sang-Woo;Kwon, Se-Ik;Kim, Nam-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2016.05a
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    • pp.409-411
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    • 2016
  • Salt and pepper noise is caused by various causes such as camera malfunction, storage media memory error, and transmission channel error. Representative filters to remove salt and pepper noise include SMF(standard median filter), CWMF(center weighted median filter), and AMF(adaptive median filter). However previous filters have inadequate noise removal characteristics in high density salt-and-pepper noise environment. Therefore the study suggested a composite filter which, through noise evaluation, preserves original pixels when the central pixel is non-noise, and uses spatial weighted value mask and median when there is noise.

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A Mask-based Gaussian Noise Removal Algorithm in Spatial Space

  • Seo, Hyun-Soo;Kim, Nam-Ho
    • Journal of information and communication convergence engineering
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    • v.5 no.3
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    • pp.259-264
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    • 2007
  • According to the development and wide use of broad band internet etc., diverse application technologies using large capacity data such as images have been progressed and in these systems, for accurate acquisition and precise applications of an original signal, the degradation phenomenon generated in the transmission process etc. should be removed. Noises have become known as the main cause of the degradation phenomenon and especially Gaussian noise represents characteristics occurring dependently in image signals and degrades detail information such as edge. In this paper, we removed Gaussian noise using a subdivided nonlinear function according to a threshold value and analyzed the histogram acquired from an edge image to establish a threshold value adaptively, and strengthened detail information of image by using the postprocessing. In simulation results, the proposed method represented excellent performance from comparison of MSE with existing methods.

Adaptive Nonlinear Filter for Removal of Salt-Pepper Noise in Infrared Image (적외선 영상의 Salt-Pepper 잡음제거를 위한 적응 비선형 필터)

  • Lee, Je-Il;Kim, Sung-Hwan
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.55 no.9
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    • pp.429-434
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    • 2006
  • In this paper, detection based - adaptive windowed nonlinear filter(DB-AWNF) is proposed for removing salt-pepper noise in infrared image. This filter is composed of impulse detector and window-size-variable median filters. Impulse detector checks whether current pixel is impulse or not using range function and nonlinear location estimator. If impulse is detected, current pixel is filtered according to four kinds of local masks by use of median filter. If not, current pixel is delivered to output like identity filter. In Qualitative view, the proposed could have removed heavy corrupted noise up to 30% and reserved the details of image. In quantitative view, PSNR was measured. The proposed could have about 12-31[dB] more improved performance than those of median $(3{\times}3)$ filter and 13-29[dB] more improved performance than those of median $(5{\times}5)$ filter.

Removal of Salt and Pepper Noise using Spatial Weighted Value (공간 가중치를 이용한 Salt and Pepper 잡음 제거)

  • Hong, Sang-Woo;Hwang, Yeong-Yeun;Kim, Nam-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2015.10a
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    • pp.927-929
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    • 2015
  • With rapid progress in digital technology, demand for multi-media imaging devices is increasing. But noise occurs due to various reasons during the process of acquiring, transmitting or processing the image data. Filters used to remove salt and pepper noise include CWMF and AWMF. In areas where the noise density is high, the removal of noise is undermined. This paper suggests an algorithm that preserves the edge while removing noise using spatial weighted.

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