• International Journal of Internet, Broadcasting and Communication
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• 제14권1호
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• pp.116-121
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• 2022

In this paper, we propose a highly secure watermarking technique in which the watermark is multi-encrypted using the R, G, and B component pixels of color image, and then the multi-encrypted watermark is hidden in the LSB of the color image pixel. According to the technique proposed in this paper, the quality of the stego-image created by hiding the multi-encrypted watermark in the LSB of the color image is so excellent that the difference from the cover image cannot be recognized. Also, it is possible to extract the original watermark from the stego-image without loss. If the watermark is hidden in the image using the proposed technique, the security of the watermark is maintained very well because the watermark hidden in the stego-image is multi-encrypted. The proposed watermarking technique can be used in the applications such as military and intellectual property protection requiring high security.

• 전자공학회논문지B
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• 제33B권4호
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• pp.101-110
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• 1996

Color image quantization is a process of selecting a set of colors to display an image with some representative colors without noticeable perceived difference. It is very important in many applications to display a true color image in a low cost color monitor or printer. the basic problem is how to display 224 colors with 256 or less colors, called color palette. In this paper, we propose an algorithm to design the 256 or less size color palette by using spatial maskin geffect of HVS and subjective distortion measure weighted by color palette by using spatial masking effect of HVS and subjective distortion measure weighted by color activity in 4*4 local region in any color image. The proposed algorithm consists of octal prequantization and subdivision quantization processing step using the distortion measure and modified Otsu's between class variance maximization method. The experimental results show that the proposed algorithm has higher visual quality and needs less consuming time than conventional algorithms.

• Current Optics and Photonics
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• 제3권5호
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• pp.408-414
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• 2019

In this paper we propose a method to generate a true color image in scanning white-light interferometry (SWLI). Previously, a true color image was obtained by using a color camera, or an RGB multichannel light source. Here we focused on acquiring a true color image without any hardware changes in basic SWLI, in which a monochrome camera is utilized. A Fourier transform method was used to obtain the spectral intensity distributions of the light reflected from the sample. RGB filtering was applied to the intensity distributions, to determine RGB values from the spectral intensity. Through color corrections, a true color image was generated from the RGB values. The image generated by the proposed method was verified on the basis of the RGB distance and peak signal-to-noise ratio analysis for its effectiveness.

• 디지털산업정보학회논문지
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• 제15권1호
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• pp.99-107
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• 2019

Retinex-based image enhancement is a technique that utilizes the property that the human visual characteristics are sensitive to the difference from the surrounding pixel value rather than the pixel value itself. These Retinex-based algorithms show different characteristics of the improved image depending on the applied color space or gamma correction. In this paper, we set eight different experimental conditions according to the application of color space and gamma correction, and analyze the objective and subjective performance of each Retinex based image enhancement algorithm and apply it to the implementation of Retinex based algorithm. In the case of gamma correction, quantitative low entropy images and low contrast images are obtained. The application of Retinex technique in HSI color space rather than RGB color space is found to be high in overall subjective image quality as well as maintaining color.

• 패션비즈니스
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• 제8권3호
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• pp.49-58
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• 2004

In the modern society, already a popular and public part of fashion, hair coloring has the effect of optical illusion on image. This study therefor aims to reveal the effects of varied and fashionable hair coloring on the body images. This is a combination of an actual examination and an experimental study. In order to know the effects of hair colors on body image, 230 female collegians residing in Busan were given a questionnaire on the reality of hair dyeing. Based on the actual research, one subject was selected and stimuli were manufactured. The analysis and examination of the effects of hair dyeing have produced the following conclusions. (1) As a result of dispersion analysis about the image effect according to hair colors, a meaningful difference is recognized in the item and indicates that hair color variation influences the image effect. (2) As a result, extracting the factors that hair colors can influence the image, 3 factors were extracted. The first factor is an intellectual image, the second factor is an active image, and the third factor is a comfortable image. (3) Image effect in hair colors are as same next. Red and Orange color clearly indicate the image of 'charismatic', 'lively', 'positive', 'active', 'light' and 'gorgeous'. Blue and Green color indicates the image of 'unfriendly', 'hard', 'cold' and 'uneasy'. White color indicates the image of 'unfriendly', 'charismatic', 'gorgeous' and 'impure' then Black color has images of 'friendly', 'intellectual', 'indignified' and 'pure'. In other words, the result indicates rather a different tendency comparison with the general color image.

• 한국실내디자인학회논문집
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• 제18권6호
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• pp.166-175
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• 2009

Many cities in developed countries are showing their unique urban image reflecting their own culture, history, and aesthetic tastes. Especially color, one of the major design elements, has greater impact than other visual factors to form an unique urban characteristic. Despite the long history and cultural background, Seoul as a capital city of Korea does not have been successful to show an unique city image with the perspective of color. As a leading city of design, Seoul is trying to make its own urban identity through the symbolic environmental color, 'Seoul Color'. The purpose of this study is to identify the perception on the Seoul Color established by Seoul City among design practitioners and to suggest strategies for implementing the 'Seoul Color' in various fields of environmental design to set up un unique urban image of Seoul City. For this purpose, questionnaire survey was used and 77 questionnaires were analysed. Although most of the respondents did not know the 'Seoul Color', they recognized the importance of it as a major tool of building an unique urban identity of Seoul City. Respondents recognized the representing color image of Seoul as gray. Therefore, it shows a need for environmental policy to make an eco-friendly and lively city image of Seoul instead of current monotonous image. Also in order to make a unique urban image of Seoul city, 'Seoul Color' should be applied to the shape of landscape of Seoul differently. In addition, many strategies including advertisement, education, making up obvious goals for using the 'Seoul Color', and so on were suggested as conclusion.

• 한국정보통신학회논문지
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• 제6권5호
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• pp.789-795
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• 2002

컬러 이미지는 Gray Scale 이미지와는 달리 3가지 채널의 조합으로 이루어지고 방대한 정보량 때문에 효과적인 이미지 분할이 어렵다. 본 논문에서는 범용성 있는 Color Morphological Pyramids(CMP)구조를 제안하고, 그를 이용한 이미지 분할을 보인다. 이미지 피라미드 구조는 최초 이미지의 반복적인 필터링과 샘플링에 의해 면적비가 $2^{\int}({\int}=1,2,....,N)$이 되는 순차적 이미지 계열이다. 본 방법에서는 CMP를 이용하여 RGB, HSI, CMY 등의 컬러 공간에서 연속적인 필터링 처리로 불필요한 크기의 물체 및 잡음을 제거하고, 다운샘플링과정으로 해상도를 낮춰준다. 생성된 CMP에서 인접 레벨 이미지간에는 이웃한 픽셀 벡터간의 상대거리를 이용한 연결식을 사용하여 새 레벨의 이미지를 생성한 후 이를 이미지 분할한다. 이미지 분할실험을 통하여 본 방법의 유효성을 검증한다.

• 대한전자공학회논문지SP
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• 제43권6호
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• pp.65-84
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• 2006

본 논문에서는 개선된 영상 생성 모델을 제시하고, 제시된 모델에 기반한 칼라 영상 향상을 제안한다. 제시된 영상 생성 모델에서는 입력 영상을 전역 조명 성분과 국부 조명 성분, 그리고 반사율 성분의 곱으로 표현한다. 제안된 칼라 영상 향상에서는 RGB 입력 칼라 영상을 HSV 칼라 영상으로 변환한 다음, 백색광 조명 상태라는 가정 하에 개선된 영상 생성 모델에 근거하여 V 성분 영상만을 향상한다. 전역 조명 성분은 입력 V 성분 영상에 유효 영역이 넓은 선형 저대역 필터를 적용하여 추정하고, 국부 조명 성분은 입력 V 성분 영상에서 추정된 전역 조명 성분이 제거된 영상에 유효 영역이 좁은 JND (just noticeable difference) 기반의 비선형 저대역 필터를 적용하여 추정한다. 그리고 반사율 성분은 입력 V 성분 영상에 추정된 전역 조명 성분과 국부 조명 성분을 나누어 추정한다. 이어서 이들 추정된 성분에 감마 수정을 각각 적용하고 그 결과들을 곱하여 출력 V 성분 영상을 얻은 다음 히스토그램 모델링을 적용하여 최종 출력 V 성분 영상을 얻는다. 마지막으로 최종 출력 V 성분 영상과 입력 H 성분 영상 및 S 성분 영상으로부터 출력 RGB 칼라 영상을 얻는다. 실험 결과 제안된 방법은 NASA 홈 페이지로부터 다운받은 칼라 영상과 MPEG-7 CCD 칼라 영상으로 구축한 시험 영상 데이터 베이스에 대하여 후광 효과가 거의 억제되고 색상 변화가 거의 없으면서 전역 대비와 국부 대비를 동시에 잘 증가시키는 것을 확인하였다.

• 한국통신학회논문지
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• 제22권5호
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• pp.889-898
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• 1997

Most general content-based image retrieval techniques use color and texture as retrieval indices. Spatial information is not used to color histogram and color pair based on color retrieval techniques. This paper proposes the selection of a set of representative in the duplicated color histogram, the analysis of spatial information of the selected colors and the image retrieval process based on the duplicated color histogram and spatial information. Two color historgrams for background and object are used in order to decide on color selection in the duplicated color histogram. Spatial information is obtained using a maximum entropy discretization. A retrieval process applies to duplicated color histogram and spatial to retrieve input images and relevant images. As the result of experiment of the image retrieval, improved color his togram and spatial information method hs increased the retrieval effectiveness more the color histogram method and color pair method.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권1호
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• pp.570-595
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• 2017

Robust and perceptually-adaptive image watermarking algorithms have mainly targeted gray-scale images either at the modeling or embedding levels despite the widespread availability of color images. Only few of the existing algorithms are specifically designed for color images where color correlation and perception are constructively exploited. In this paper, a new perceptual and high-capacity color image watermarking solution is proposed based on the extension of Tsui et al. algorithm. The $CIEL^*a^*b^*$ space and the spatio-chromatic Fourier transform (SCFT) are combined along with a perceptual model to hide watermarks in color images where the embedding process reconciles between the conflicting requirements of digital watermarking. The perceptual model, based on an emerging color image model, exploits the non-uniform just-noticeable color difference (NUJNCD) thresholds of the $CIEL^*a^*b^*$ space. Also, spread-spectrum techniques and semi-random low-density parity check codes (SR-LDPC) are used to boost the watermark robustness and capacity. Unlike, existing color-based models, the data hiding capacity of our scheme relies on a game-theoretic model where upper bounds for watermark embedding are derived. Finally, the proposed watermarking solution outperforms existing color-based watermarking schemes in terms of robustness to standard image/color attacks, hiding capacity and imperceptibility.