• 제목/요약/키워드: color systems

검색결과 1,304건 처리시간 0.173초

Color accuracy of imaging using color filters

  • Boher, P.;Leroux, T.;Patton, V. Collomb;Bignon, T.
    • Journal of Information Display
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    • 제13권1호
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    • pp.7-16
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    • 2012
  • In this paper, the problem concerning the color accuracy of imaging systems using color filters is examined. It is shown that the only solution to the problem is to build systems with the spectral response matching the CIE curves as closely as possible. If the spectral response does not closely match the CIE curves, it was demonstrated that calibration cannot solve the problem and will result in very unstable colorimeters. A practical solution that uses telecentric lenses on the sensor side in addition to dedicated color filters for each CCD detector is presented. For systems that closely match the CIE curves, an innovative method of improving the color accuracy based on the precise measurement of the spectral response is presented. The small discrepancies in the spectral response with regard to the CIE curves are corrected in different ways during the measurements. Finally, it is shown that the tristimulus calibration that is used for display measurement is very unstable for systems without CIE matching and is much more stable with systems that closely match the CIE curves.

On Color Cluster Analysis with Three-dimensional Fuzzy Color Ball

  • Kim, Dae-Won
    • 한국지능시스템학회논문지
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    • 제18권2호
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    • pp.262-267
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    • 2008
  • The focus of this paper is on devising an efficient clustering task for arbitrary color data. In order to tackle this problem, the inherent uncertainty and vagueness of color are represented by a fuzzy color model. By taking a fuzzy approach to color representation, the proposed model makes a soft decision for the vague regions between neighboring colors. A definition on a three-dimensional fuzzy color ball is introduced, and the degree of membership of color is computed by employing a distance measure between a fuzzy color and color data. With the fuzzy color model, a novel fuzzy clustering algorithm for efficient partition of color data is developed.

퍼지컬러 모델을 이용한 컬러 데이터 클러스터링 알고리즘1 (Color Data Clustering Algorithm using Fuzzy Color Model)

  • Kim, Dae-Won;Lee, Kwang H.
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2002년도 춘계학술대회 및 임시총회
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    • pp.119-122
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    • 2002
  • The research Interest of this paper is focused on the efficient clustering task for an arbitrary color data. In order to tackle this problem, we have tiled to model the inherent uncertainty and vagueness of color data using fuzzy color model. By laking a fuzzy approach to color modeling, we could make a soft decision for the vague regions between neighboring colors. The proposed fuzzy color model defined a three dimensional fuzzy color ball and color membership computation method with the two inter-color distance measures. With the fuzzy color model, we developed a new fuzzy clustering algorithm for an efficient partition of color data. Each fuzzy cluster set has a cluster prototype which is represented by fuzzy color centroid.

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QUALITY IMPROVEMENT OF COMPRESSED COLOR IMAGES USING A PROBABILISTIC APPROACH

  • Takao, Nobuteru;Haraguchi, Shun;Noda, Hideki;Niimi, Michiharu
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 2009년도 IWAIT
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    • pp.520-524
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    • 2009
  • In compressed color images, colors are usually represented by luminance and chrominance (YCbCr) components. Considering characteristics of human vision system, chrominance (CbCr) components are generally represented more coarsely than luminance component. Aiming at possible recovery of chrominance components, we propose a model-based chrominance estimation algorithm where color images are modeled by a Markov random field (MRF). A simple MRF model is here used whose local conditional probability density function (pdf) for a color vector of a pixel is a Gaussian pdf depending on color vectors of its neighboring pixels. Chrominance components of a pixel are estimated by maximizing the conditional pdf given its luminance component and its neighboring color vectors. Experimental results show that the proposed chrominance estimation algorithm is effective for quality improvement of compressed color images such as JPEG and JPEG2000.

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컬러교정인쇄에 대한 룩업테이블의 적용방법에 관한 연구 (A Study on the Application Method of Look-up Table to Color Proofing Systems)

  • 송경철;강상훈
    • 한국인쇄학회지
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    • 제18권1호
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    • pp.35-45
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    • 2000
  • Recently, as the prepress mainstream is changed to the digital workflow, various digital proofing systems such as high price dye sublimation printers and low price ink jet printers are widely used in printing industry. However, most of the digital proofing devices have lower resolution than analog proofing systems and differ with actual color presses in the color gamuts. Therefore, proper color compensations are needed for digital color proofing in order to match colors between the proofs and the press sheets. This study shows the application method of Look-up Table to the digital color proofer of Rainbow, the analog proofer of Matchprint-II, and an actual offset press is effective on the color compensations.

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3판식 액정 프로젝션 시스템의 다이크로익 미러의 색채학적 설계 (Colorimetric Design of Dichroic Mirrors in 3-LCD Projection Systems)

  • 김지홍
    • 전자공학회논문지S
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    • 제35S권9호
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    • pp.70-77
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    • 1998
  • 3판식 액정 프로젝션 시스템에서 색분리/합성용으로 사용되는 다이크로믹 미러의 새로운 설계 방법을 제안한다. 색재현 성능의 기준으로 단순히 밝거나 색순도에 근거한 방법이 아닌, 3차원 균등색공간에서의 색영역의 체적을 최대화 시키도록 설게 변수를 최적화한다. 제안된 설계 방법에서는 액정 프로젝션 시스템의 색재현의 색채학적 분석을 통해, 2개의 대표적 시청 조건에서 CIELUV 균등색공간의 재현 가능한 색영역의 체적을 최대화하도록 Dichroic Mirror/Filter의 경계 파장의 최적치가 구해진다.

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피부병변의 정량적 평가를 위한 디지털 컬러 영상 시스템 (Digital Color Imaging Systems for Quantitative Evaluation of Skin Lesions)

  • 한병관;정병조
    • 대한의용생체공학회:의공학회지
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    • 제28권2호
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    • pp.195-198
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    • 2007
  • In this paper, we introduce a digital cross-polarization and fluorescent color imaging system for quantitative evaluation of skin lesions. We describe the characterization of the imaging systems and the quantitative image analysis methods to show the feasibility for quantitative evaluation of skin lesions. The polarization color image was used to compute erythema and melanin index image which are useful for quantitative evaluation of pigmentation and vascular skin lesions, respectively. The fluorescent color image was used to quantitatively evaluate "sebum" and "vitiligo". In quantitative evaluation of various skin lesions, we confirmed the clinical efficacy of the imaging systems for dermatological applications. Finally, we sure that the imaging systems can be utilized as important assistant tools for the evaluation of skin lesions by providing reproducible quantitative result for widely distributed skin lesions.

컬러인쇄공정에 대한 룩업테이블의 적용방법에 관한 연구 (A Study on the Application Method of Look-up Table to Color Printing Process)

  • 송경철;강상훈
    • 한국인쇄학회:학술대회논문집
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    • 한국인쇄학회 2000년도 추계 학술 발표회 논문집
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    • pp.17-28
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    • 2000
  • Recently, as the prepress mainstream is changed to the digital workflow, various digital proofing systems such as high price dye sublimation printers and low price ink jet printers are widely used in printing industry. However, most of the digital proofing devices have lower resolutions than analog proofing systems and differ with actual color presses in the color gamuts. Therefore, proper color compensations are needed for digital color proofing in order to match color between the proofs and the press sheets. In this paper, we used 3-dimensional look-up table(LUT) and tetrahedral interpolation method for the color space conversion between the device independent color space(CIEXYZ or Lab) and the device dependent color space(CMY) to reduce the color differences between the original copy and digital color proofs and the press sheets.

콜로이드 골드 나노입자의 단백질 수송성 평가법 (Protein-Coating Evaluation Method of Colloidal Gold Nanoparticles)

  • 김미영;노상명;김정목;최한곤;김정애;오유경
    • Journal of Pharmaceutical Investigation
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    • 제34권6호
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    • pp.465-469
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    • 2004
  • Colloidal gold nanoparticles might be of use as nano scale delivery systems of various therapeutic materials in the future. Recent studies have reported the feasibility of colloidal gold nanoparticles as gene delivery systems or protein delivery systems. In this study, we aimed to develop a short-step method useful for screening the optimal coating conditions of colloidal gold nanoparticles with proteins. We observed that colloidal gold nanoparticles have properties of changing its unique color when they were exposed to NaCl solution. Taking advantage of the color changing properties of colloidal gold nanoparticles, we applied the color testing method of colloidal gold nanoparticles solutions for evaluating the protein coating nature. Using bovine serum albumin as a model protein, we tested the protein coating of colloidal gold nanoparticles via the color change upon NaCl addition. The optimal coating concentration and coating conditions of colloidal gold nanoparticles with bovine serum albumin were fixed using the color testing methods. We suggest that the color testing method might be applied to optimize the coating condition of colloidal gold nanoparticles with other therapeutic proteins.

Color Prediction of Yarn-dyed Woven Fabrics -Model Evaluation-

  • Chae, Youngjoo;Xin, John;Hua, Tao
    • 한국의류학회지
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    • 제38권3호
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    • pp.347-354
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    • 2014
  • The color appearance of a yarn-dyed woven fabric depends on the color of the yarn as well as on the weave structure. Predicting the final color appearance or formulating the recipe is a difficult task, considering the interference of colored yarns and structure variations. In a modern fabric design process, the intended color appearance is attained through a digital color methodology based on numerous color data and color mixing recipes (i.e., color prediction models, accumulated in CAD systems). For successful color reproduction, accurate color prediction models should be devised and equipped for the systems. In this study, the final colors of yarn-dyed woven fabrics were predicted using six geometric-color mixing models (i.e., simple K/S model, log K/S model, D-G model, S-N model, modified S-N model, and W-O model). The color differences between the measured and the predicted colors were calculated to evaluate the accuracy of various color models used for different weave structures. The log K/S model, D-G model, and W-O model were found to be more accurate in color prediction of the woven fabrics used. Among these three models, the W-O model was found to be the best one as it gave the least color difference between the measured and the predicted colors.