• Journal of the Institute of Electronics Engineers of Korea SP
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• v.40 no.1
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• pp.43-50
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• 2003

Today, the demand of image acquisition systems grows as the multimedia applications go on increasing greatly. Among the systems, film scanner is one of the systems, which can acquire high quality and high resolution images. However due to the nonlinear characteristic of the light source and sensor, colors of the original film image do not correspond to the colors of the scanned image. Therefore color correction mr the scanned digital image is essential in the film scanner. In this paper, polynomial regression method is applied for the color correction to CIE $L^{*}$ $a^{*}$ $b^{*}$ color model data converted from RGB color model data. A1so a film scanner hardware with 12 bit color resolution for each R, G, B and 2400 dpi was implemented by using TMS320C32 DSP chip and high resolution line sensor. An experimental result shows that the average color difference ($\Delta$ $E^{*}$$_{ab}$ ) is reduced from13.48 to 8.46.6.6.6.6.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.9
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• pp.119-126
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• 2013

In this paper, we propose a chromatic aberration removal algorithm in image capture devices, which considers local properties of the image. Chromatic aberration is generated by the fact that the refractive index of the lens is different for different wavelengths, which produces color artifacts on strong edge due to misalignment of RGB channels. Under the characteristics of the artifacts, the proposed algorithm first estimates the regions with the apparent color artifacts as the neighborhoods of the strong edge. In the regions, the proposed algorithm removes the color artifacts by matching the edges of RGB channels. The widely used conventional methods based on global image warping could not remove the color artifacts of longitudinal chromatic aberration and purple fringing identified by the image sensor, whereas the matching process of the proposed method could reduce them. Experimental results show that the proposed algorithm outperforms the conventional methods on objective and subjective criteria.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.7 no.4
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• pp.19-25
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• 1993

The purpose of this study was to investigate the scope of color perception for Korean standard color. 99 male and 126 female university students were selected as the random sample. Color perception was made with the naked eyes. Minolta Chroma Meter CR 300 was used for physical measurement of the color. The results were as follows, 1) Color perception was classified into four large groups: simple group includes Red, Yellow Red, Pale Red Yellow, Yellow, X( -axis)group includes Pale Yellow Red, Pale Green Yellow, Green Yellow, Purple, Pale Red Purple, Y( -axis)group includes Pale Blue Green, Blue Green, Pale Green Blue, Blue, Pale Ptuple Blue, complex group includes Pale Yellow Green, Green, Purple Blue, Pale Blue Purple, Red Purple, Pale Purple Red. 2) There is little difference between the values of standard color and mean percept color for Blue, Yellow, Pale Green Yellow, Green Yellow, Pale Yellow Green, Green, Pale Blue Green, Blue Green, Purple, while big difference for Blue, Pale Green Blue, Pale Red Purple, Pale Purple Red. 3) As for as sex was concerned, female is more accurate than male in color perception.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.10C
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• pp.621-628
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• 2011

The skin color has been used as important cues in the systems for detecting or recognizmg the face. However, the color difference in images under different illuminants makes it difficult to find out the skin in these systems. For solving the problem, this paper proposes a method of recovering skin colors based on well-known color constancy approaches, such as Retinex, Gray World, White Patch, and Simplified Horn. To acquire experimental images under the colored scene illumination, the effects of colored illuminants were added to source images. Next, result images, having the corrected skin color by the constancy methods, were derived from the source images. The experiment results showed that most of the skin colors in our experiments were recovered into some steady range in the color space, and that Gray World had higher performance than the other methods compared.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.44 no.4 s.316
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• pp.60-69
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• 2007

The human eye usually experiences a loss of color sensitivity when it is subjected to high levels of luminance, and perceives a discrepancy in color between high and normal-luminance displays, generally known as a hue shift. Accordingly, this paper models the hue-shift phenomenon and proposes a hue-correction method to provide perceptual matching between high and normal-luminance displays. The value of hue-shift is determined by perceived hue matching experiments. At first the phenomenon is observed at three lightness levels, that is, the ratio of luminance is the same between high and normal-luminance display when the perceived hue matching experiments we performed. To quantify the hue-shift phenomenon for the whole hue angle, color patches with the same lightness are first created and equally spaced inside the hue angle. These patches are then displayed one-by-one on both displays with the ratio of luminance between two displays. Next, the hue value for each patch appearing on the high-luminance display is adjusted by observers until the perceived hue for the patches on both displays appears the same visually. After obtaining the hue-shift values, these values are fit piecewise to allow shifted-hue amounts to be approximately determined for arbitrary hue values of pixels in a high-luminance display and then used for correction. Essentially, input RGB values of an image is converted to CIELAB values, and then, LCh (lightness, chroma, and hue) values are calculated to obtain the hue values for all the pixels. These hue values are shifted according to the amount calculated by the functions of the hue-shift model. Finally, the corrected CIELAB values are calculated from corrected hue values, after that, output RGB values for all pixels are estimated. For evaluation, an observer's preference test was performed with hue-shift results and Almost observers conclude that the images from hue-shift model were visually matched with images on normal luminance display.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2002.11a
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• pp.261-266
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• 2002

본 연구에서는 광원의 색온도와 연색성의 차이에 의한 밝음의 느낌과 조도와의 관계를 밝히기 위하여 이종 램프간, 또한 동종 램프 간의 비교 실험을 시각 대상물로 흑백 인쇄문자지와 색상지를 사용하여 수행하였다. 현재 널리 사용되고 있는 백열전구, 형광램프, 고압 나트륨램프, 메탈핼라이드램프, 무전극 방전램프를 대상으로 실험을 수행하여, 램프 간 실험 결과의 통계처리 결과, 백열전구와 무전극 방전램프, 주광색 형광램프와 무전극 방전램프, 고압 나트륨램프와 무전극 방전램프, 메탈핼라이드램프와 무전극 방전램프는 유의수준 5[%] 이내에서 결과에 분명한 차이가 있음이 밝혀졌다.

• Proceedings of the Korean Information Science Society Conference
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• 2006.06c
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• pp.100-102
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• 2006

인터넷 환경에서 데이터 저장과 전송을 위한 표준으로 XML이 부각되고 있다. 이에 따라 XML자체에 대한 관심뿐 아니라 XML 질의 처리를 위한 연구도 활발하게 이루어지고 있다. 이러한 연구는 XML문서 자체의 내용 뿐 아니라 구조에 대한 질의에 대해서도 진행되고 있다. 구조에 대한 질의를 위해 경로 질의가 사용되고 있으며, 최근 경로 질의를 효과적으로 처리하기 위하여 여러 가지 색인 기법들이 연구되고 있다. 본 연구에서는 기존에 제안된 대표적인 두 가지 색인기법인, 경로 색인 기법과 구조 조인 기법에 대한 특징에 대해 살펴보고, 구조 조인 기법에 대한 기존연구의 알고리즘의 성능을 개선시킬 수 있는 메커니즘을 제안하였다. 기존 연구에서는 질의에 해당하는 모든 엘리먼트들을 비교하여 결과를 뽑아내지만 제안한 메커니즘은 입력 값의 형태를 변형하여 비교하는 엘리먼트의 수를 줄여 더 적은 조인연산을 수행함으로서 성능을 향상시킬 수 있었다. 이러한 결과를 4절에서 실험을 통해 검증하였다. 실험 결과 기존 방법에 비해 실험한 질의에 따라 최대 34%, 최소 7%의 성능 향상을 이룰 수 있었다.

• Journal of the Korean Society for information Management
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• v.13 no.1
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• pp.19-43
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• 1996

The indexing languages and techniques were ~ u ~ e y e d for Korean textual databases, and retrieval effectivenesses of two indexing languages were evaluated in an online searching experiment. It was found that most of the Korean textual databases surveyed employ natural language indexing by either an automatic or a manual method, and that natural language indexing may outperform controlled language indexing if appropriate search strategies are employed.

• Journal of Korea Multimedia Society
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• v.13 no.5
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• pp.674-683
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• 2010

For the purpose of color reproduction under standard viewing conditions, recently, color display devices have developed for the colorimetric color reproduction. However the real viewing condition of color display devices is quite different from that. Therefore, it is very important for reproduced colors viewed under real conditions to match the color appearance under standard situations. There are various models that can be used to reproduce corresponding colors considering the chromatic adaptation of the human visual system. However neutral point or chromatic adaptation for the luminance level is not enough. In this paper, we propose a model that find adapting white points for the variations of the luminance levels under the same illuminant. This model is modeled by the proportion of Euclidian distance for luminance level. It is the adapting white function of the sigmoid type for surround luminance level. In the model, the optimal coefficients are obtained from the Hunt's experimental result. It is applied in the chromatic adaptation model using the neutral point of the various viewing conditions. And the neutral point can be used as the theoretical standard which determines the reference white of the color display devices.

• The Journal of the Korea Contents Association
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• v.19 no.4
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• pp.663-674
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• 2019

The background of the study is to experiment with the color glass plaster technique and the resist printing technique which are newly developed with the motif of natural leaves, and to make an interior vase added with new and unique decoration by fusing with ceramic vases. First research and development method is to describe the color glass plaster technique. Second is to explain the resist printing technique and study the decoration method. Third is to examine the history and kinds of vase. And lastly, it is to design 16 vases contemporarily, and use the leaves to experiment with oxidation and reduction of white porcelain and celadon. This experiment acquired the unique color expression by yaobian, and the soft, warm brown resist printing gradation was formed around the leaves. It will get good effects and results by expanding and applying the unique experiment effects to living interior porcelain, molding porcelain, and industrial porcelain.