• Title/Summary/Keyword: Edge restoration

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Image restoration by Adaptive Regularization Considering the Edge Direction (윤곽 방향을 고려한 적응 정칙화 영상 복원)

  • 김태선
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.9B
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    • pp.1588-1595
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    • 2000
  • To restore image degraded by out-of-focus blur and additivie noise a regularized iterative restoration is used. In concentional method, regularization is usually applied to all over the image without considering the local characteristics of image. As a result, ringing artifacts appear in edge regions and the noise amplification is introduced in flat regions. To solve this problem we propose an adaptive regularization iterative restoration using directional regularization operator considering edges in four directions and the regularization operator with on direction for flat regions. We verified that the proposed method show better results in the suppression of the noise amplification in flat regions, and introduced less ringing artifacts in edge regions. As a result it showed visually better image and improved better ISNR further than the conventional methods.

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Restoration of a Bi-level Waveform by Estimation of Edge Locations (에지 위치 추정을 통한 이진 파형의 복원)

  • Kim, Jeong-Tae
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.55 no.7
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    • pp.327-331
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    • 2006
  • We have proposed an image restoration method for a bi-level waveforms whose number of edges is known to us. Based on the information, we parametrize a bi-level waveform using the locations of edges and restore the waveform by estimating the parameter. We estimated the locations by maximizing the correlation coefficients between the hi-level waveform and the measured waveform. In experiments using two dimensional barcode images of the PDF417 specification, the proposed method showed better performance than conventional methods in the sense that the proposed method was able to decode barcode images that were not decoded by the conventional methods.

THE CONSTRAINED ITERATIVE IMAGE RESTORATION ALGORITHM USING NEW REGULARIZATION OPERATORS

  • Lee, Sang-Hwa;Lee, Choong-Woong
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 1997.06a
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    • pp.107-112
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    • 1997
  • This paper proposes the regularized constrained iterative image restoration algorithms which apply new space-adaptive methods to degraded image signals, and analyzes the convergence condition of the proposed algorithm. First, we introduce space-adaptive regularization operators which change according to edge characteristics of local images in order to effectively prevent the restored edges and boundaries from reblurring. And, pseudo projection operator is used to reduce the ringing artifact which results from extensive amplification of noise components in the restoration process. The analysed algorithm is stable convergent to the fixed point. According to the experimental results for various signal-to-noise ratios(SNR) and blur models, the proposed algorithms other methods and is robust to noise effects and edge reblurring by regularization especially.

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Compression and Restoration of DNA Image Using JPEG and Edge Information (JPEG과 윤곽선 정보를 이용한 유전자 영상의 압축 및 복원)

  • Shin, Eun-Kyung;Lee, Youn-Jung;Kim, Do-Nyun;Cho, Dong-Sub
    • Proceedings of the KIEE Conference
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    • 1996.07b
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    • pp.1368-1370
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    • 1996
  • The Information of Edges which takes small area comparing with the total image is very important in DNA images as well as general images. DNA image is the object should be managed by computing and it's demanding information is less than general images, but the accuracy is more important In a huge DNA image processing system such as DNA Information Bank, the performance depends on the size of image. In this paper, we extract the edge information and make it as a binary image. To reduce the size of the original image, it was applied by JPEG image compression method. The compressed image is combined with edge information when they are restored. As a result, Both the image compression ratio and restoration quality are optimized without the loss of critical information.

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An Adaptive Image Restoration Algorithm Using Edge Detection Based on the Block FFT (블록 FFT에 기초한 에지검출을 이용한 적응적 영상복원 알고리즘)

  • Ahn, Do-Rang;Lee, Dong-Wook
    • Proceedings of the KIEE Conference
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    • 1998.11b
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    • pp.569-571
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    • 1998
  • In this paper, we propose a method of restoring blurred images by an edge-sensitive adaptive filter. The direction of the edge is estimated using the properties of 2-D block FFT. Reduction of blurring due to the added noise during image transfer and the focus of lens caused by shooting a fast moving object is very important. To remove this phenomenon effectively, we can use the edge information obtained by processing the blurred images. The proposed algorithm estimates both the existence and the direction of the edge. On the basis of the acquired edge direction information, we choose the appropriate edge-sensitive adaptive filter, which enables us to get better images than images obtained by methods not considering the direction of the edge. The performance of the proposed algorithm is shown in the simulation result.

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FINITE ELEMENT ANALYSIS OF STRESS DISTRIBUTION ACCORDING TO THE METHOD OF RESTORATION AFTER ROOT CANAL THERAPY (상악 중절치 근관치료후 수복 방법에 따른 응력 분포의 유한 요소 분석)

  • Lee, Jae-Young;Lee, Chung-Sik
    • Restorative Dentistry and Endodontics
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    • v.19 no.2
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    • pp.549-567
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    • 1994
  • Restoration of severly damaged teeth after endodontic treatment had been an interest to many dentists, and it is a fact that there have been lots of studies about it. In these days, although we have used Para-Post, pins, threaded steel post, cast gold post and core, and so on, as a method of restoration frequently, it has been in controversy with the influence of them on the teeth and surrounding periodontal tissue. In this study, we assume that the crown of the upper incisor have severly damaged, so, after the root canal therapy, 4 types of restoration had been carried out; 1) coronal-radicular amalgam restoration, 2) after setting up the Para-Post, restore with composite resin core only, 3) after setting up the Para-Post; restore with amalgam core, then cover with the PPM crown 4) after setting up the Para-Post, restore with composite core, then cover with the PPM crown. After restoration, in order to observe the concentration of stress at internal portion of the teeth and the sourrounding periodontal tissue, developing a 2-dimensional finite element model of labiopalatal section, then loading forces from 3 direction - direction of 45 degrees from lingual side near the incisal edge, horizontal direction from labial height of contour, vertical direction at the incisal edge-were applied. The analyzed results were as follows: 1. Stress of the normal central incisor was concentrated on the dentin aroundpulp chamber, labiocervical portion of a tooth and root apex, but with the alveolar bone, in the case of load from the direction of 45 degrees from lingual side near the incisal edge showed remarkable concentration of stress: 2. Coronal-radicular amalgam technique -showed less concentration of stress on the root and surrounding periodontal tissue than the restoration with the Para-Post. 3. The von Mises equivalent stress on the Para-Post showed maximum value at root-core junction rather than both ends and model with PPM restoration with amalgam core showed the least concentration of stress. Only the force from horizontal direction showed large shear stress on internal portion of the root, root apex and alveolar bone. 4. PPM crown with composite core rarely showed the concentration of stress on root and periodontal tissue. 5. As for alveolar bone, remarkable shear stress was concentrated on labial and palatal side by horizontal load.

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Vegetation Restoration Model of Pinus thunbergii in Urban Areas (도시지역 곰솔림의 식생복원모델)

  • Kim, Seok-Kyu
    • Journal of Environmental Impact Assessment
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    • v.20 no.2
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    • pp.151-162
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    • 2011
  • The purpose of this study is suggest to restoration model of Pinus thunbergii in Saha-gu, Busan Metropolitan City. The result of this study is summarized as follows; As the results of this study, vegetation restoration model is presented by separating community planting and edge planting. The community planting species of tree layer were Pinus thunbergii and Quercus acutissima and Quercus dentata and Quercus serrata and Quercus alienna and Quercus variabilis. The community planting species of subtree layer were Platycarya strobilacea and Prunus sargentii and Styrax japonica and Eurya japonica and Morus bombycis. The community planting species of shrub layer are Ulmus pavifolia and Ulmus davidiana and Lindera obtusiloba and Elaeagnus macrophylla and Mallotus japonicus and Ligustrum obtusifolium and Sorbus alnifolia and Rhus trichocarpa and Zanthoxylum schinifolium and Rosa wichuraiana and Rhus chinensis and Viburnum erosum and Rhododendron mucronulatum and Rhododendron yedoense and Indigofera pseudotinctoria. And the planting species of edge vegetation are Japanese Angelica and Symplocos chinensis and Pittosporum tobira and Lespedeza maximowiczii and Lespedeza bicolor and Rubus coreanus and Rubus idaeus and Vitis thunbergii and Ampelopsis brevipedunculata and Rosa multiflora. Considering the population of individuals up to layers in each $400m^2$ area, it was composed of 24 in tree layer, 35 in subtree layer, 410 in shrub layer and 34% herb layer in the Pinus thunbergii community. And the average of breast-high area and canopy area was $10,852cm^2$ in tree layer, in subtree layer $1,546cm^2$, in shrub layer $1,158,660cm^2$. The shortest distance between trees was calculated as 2.0m in tree layer, 1.9m in subtree layer.

JND based Illumination and Color Restoration Using Edge-preserving Filter (JND와 경계 보호 평탄화 필터를 이용한 휘도 및 색상 복원)

  • Han, Hee-Chul;Sohn, Kwan-Hoon
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.46 no.6
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    • pp.132-145
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    • 2009
  • We present the framework for JND based Illumination and Color Restoration Using Edge-preserving filter for restoring distorted images taken under the arbitrary lighting conditions. The proposed method is effective for appropriate illumination compensation, vivid color restoration, artifacts suppression, automatic parameter estimation, and low computation cost for HW implementation. We show the efficiency of the mean shift filter and sigma filter for illumination compensation with small spread parameter while considering the processing time and removing the artifacts such as HALO and noise amplification. The suggested CRF (color restoration filter) can restore the natural color and correct color distortion artifact more perceptually compared with current solutions. For the automatic processing, the image statistics analysis finds suitable parameter using JND and all constants are pre-defined. We also introduce the ROI-based parameter estimation dealing with small shadow area against spacious well-exposed background in an image for the touch-screen camera. The object evaluation is performed by CMC, CIEde2000, PSNR, SSIM, and 3D CIELAB gamut with state-of-the-art research and existing commercial solutions.

Ringing Artifact Removal in Image Restoration Using Wavelet Transform (웨이블릿 변환을 이용한 영상복원의 물결현상 제거 방법)

  • Youn, Jin-Young;Yoo, Yoon-Jong;Jun, Sin-Young;Shin, Jeong-Ho;Paik, Joon-Ki
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.45 no.6
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    • pp.78-87
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    • 2008
  • Digital image find own level core media in multimedia as image restoration technology fields, which remove degradation factor for image enhancement, have been growing. Linear space-invariant image restoration algorithm often introduce ringing artifacts near sharp intensity transition areas. This paper presents a new adaptive post-filtering algorithm for reducing ringing artifact. The proposed method extracts an edge map of the image using wavelet transform Based on the edge information, ringing artifacts are detected, and removed by an adaptive bilateral filter. Experimental results show that the proposed algorithm can efficiently remove ringing artifacts with edge preservation.

Chain code based New Decision Technique of Edge Orientation (체인코드를 이용한 새로운 에지 방향 결정 기법)

  • Sung, Min-Chul;Lee, Sang-Hwa;Cho, Nam-Ik
    • Journal of the Korea Institute of Military Science and Technology
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    • v.10 no.1
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    • pp.101-106
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    • 2007
  • In this paper, we propose chain code based decision technique of edge orientation. Edge Information is one of the most important information for handling image signals, and is applied to various civilian and military area, such as image surveillance for military reconnaissance, restoration of noised image signal, fingerprint recognition, and so on. The conventional methods to find edge orientations exploit a certain size of mask which weights for a certain direction, so they showed limitations in the case of diagonal edges except 45 degrees. We find edge orientations using chain code. According to the experiments, the proposed method shows better performance than the conventional approaches. The exact edge orientations including diagonal directions are well found.