• Journal of Korea Multimedia Society
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• v.19 no.10
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• pp.1782-1791
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• 2016

Various color spaces such as RGB, HSV, log-chromaticity have been used in the field of person re-identification. However, not enough studies have been done to find suitable color space for the re-identification. This paper reviews color invariance of color spaces by diagonal model and explores the suitability of each color space in the application of person re-identification. It also proposes a method for person re-identification based on a histogram refinement technique and some fusion strategies of color spaces. Two public datasets (ALOI and ImageLab) were used for the suitability test on color space and the ImageLab dataset was used for evaluating the feasibility of the proposed method for person re-identification. Experimental results show that RGB and HSV are more suitable for the re-identification problem than other color spaces such as normalized RGB and log-chromaticity. The cumulative recognition rates up to the third rank under RGB and HSV were 79.3% and 83.6% respectively. Furthermore, the fusion strategy using max score showed performance improvement of 16% or more. These results show that the proposed method is more effective than some other methods that use single color space in person re-identification.

• Journal of Korea Multimedia Society
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• v.17 no.7
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• pp.806-817
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• 2014

The extraction of lip region is essential to Lip Reading, which is a field of image processing to get some meaningful information by the analysis of lip movement from human face image. Many conventional methods to extract lip region are proposed. One is getting the position of lip by using geometric face structure. The other discriminates lip and skin regions by using color information only. The former is more complex than the latter, however it can analyze black and white image also. The latter is very simple compared to the former, however it is very difficult to discriminate lip and skin regions because of close similarity between these two regions. And also, the accuracy is relatively low compared to the former. Conventional analysis of color coordinate systems are mostly based on specific extraction scheme for lip regions rather than coordinate system itself. In this paper, the method for selection of effective color coordinate system and chromaticity transformation to discriminate these two lip and skin region are proposed.

• Korean Journal of Optics and Photonics
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• v.10 no.5
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• pp.379-385
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• 1999

The characteristics of image quality of a color CRT (cathode ray tube) monitor are studied by changing the contrast and brightness levels. The resolution is assessed by SQRI (square root integral) measured at 9 different combinations of the contrast and brightness levels. The chromaticity coordinates and luminances of red-green-blue channels as a function of the digital value are measured at these combinations and the relationships among the constant-channel chromaticity, color gamut, maximum luminance of a white point with the channel independence are analyzed. From the results, the optimized combination of levels is obtained.

• Journal of the Korean Ceramic Society
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• v.32 no.10
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• pp.1203-1211
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• 1995

The tests of three point bending and vickers hardness have been carried out to investigate mechanical characteristics of bioceramics for artificial dental crowns. And color and color difference test has been performed to study chromaticity changes after sintering specimens composited with glass and leucite powders. In addition, thermal dilation test has been carried out to examine bonding relations between dental porcelain and metal frame (Ni-Cr alloy). The result of three point bending test showed a maximum strength of about 68 MPa. Thermal expansion coefficient changed from 8.3$\times$10-6/$^{\circ}C$ to 13.5$\times$10-6/$^{\circ}C$ with increasing leucite content (0~30wt.%) in glass matrix. Bonding between porcelain (25% leucite-75% glass) and Ni-Cr alloy was excellent.

• Journal of Applied Reliability
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• v.12 no.4
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• pp.275-285
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• 2012

This paper presents a changes of luminescence property for converted white LEDs with the commercially available silicate phosphor. If silicate phosphor's quantity increase step by step. luminescence property will be changing. we analyze luminescence property for these change and carry out the high temperature aging test for 7,000 hours, the high temperature and humidity aging test for 7,000 hours for reliability. LED degradation not only results in reduced light output but also in color changes. so we monitor correlated color temperature (CCT), chromaticity coordinates(x, y) and spectrum intensity. Those results suggest that humidity factor more bad effect in color changes than temperature factor and Lighting quality is related with quantity of phosphor.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.41 no.5
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• pp.71-75
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• 2004

An efficient color compensation method is proposed to reduce the color difference between the camera based inspection system and the colorimeter based inspection system in a plasma display panel production line. The color compensation matrix can be constructed by using the relationship between RGB to XYZ conversion matrices, which are obtained by the RGB primaries and reference white chromaticity coordinates. Experimental results show that the non-contact color inspection system using the proposed color compensation method satisfactorily compensates the chromaticity coordinates acquired by the area color CCD camera to be matched to those measured by the colorimeter for various test color.

• Journal of the Institute of Convergence Signal Processing
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• v.2 no.4
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• pp.1-8
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• 2001

In this paper we propose high performance system with reduced hardware architecture to convert a color tone. Conversion for the color tone of a input image is necessary to calculate the color temperature of the image Conventional way of calculating the temperature uses algorithm using the method calculating 2-D chromaticity coordinates. But it requires bulky hardware[1]. This paper propose the color temperature calculation method about 1-D chromaticity coordinates that reduces the hardware complexity while keeping the performance of the 2-D color temperature algorithm . The proposed method is verified by fLCD-TV system using the Xilinx Virtex FPGA XCV 2000E-6BG560 that has 1344*806 resolution and requires a high-speed 65MHz operation.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.414-415
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• 2006

At present, Characteristic of high color reproduction for LCD products needed in Display market. Therefore, The improving methods of high color reproduction are alteration of color Filter or Red, Green, Blue phosphor alteration of CCFL. But High color reproduction phosphor is short life time as compared with conventional phosphor. In this experiment, by using split the Red, Green, Blue CCFL with high color reproduction phosphor instead of conventional high color reproduction CCFL. We knew that the high color reproduction RGB split CCFL BLU has same spectrum data and chromaticity, but has long life time as manufacturing RGB split CCFL and reduce chromaticity shift following long time discharge as compared with conventional high color reproduction CCFL.

• Journal of the Korea Institute of Military Science and Technology
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• v.10 no.3
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• pp.51-61
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• 2007

This paper concerns about the requirement analysis for night vision imaging system(NVIS), whose purpose is to intensify the available nighttime near infrared(IR) radiation sufficiently to be caught by the human eyes on a miniature green phosphor screen. The requirements for NVIS are NVIS radiance(NR), chromaticity, daylight legibility/readability, etc. The NR is a quantitative measure of night vision goggle (NVG) compatibility of a light source as viewed through goggles. The chromaticity is the quality of a color as determined by its purity and dominant wavelength. The daylight legibility/readability is the degree at which words are readable based on appearance and a measure of an instrument's ability to display incremental changes in its output value. In this paper, the requirements of NR, chromaticity, and daylight legibility/readability for Type I and Class B/C NVIS are analyzed. Also the rationale is shown with respect to those requirements.

• Korean Journal of Human Ecology
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• v.15 no.2
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• pp.283-292
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• 2006

The purpose of this study is to analyze and compare the color characteristics of preferred summer clothing textiles, such as shirts, blouse, slacks and skirt. 109 male and female college students evaluated the preference to clothing textiles in previous research and top 10 kinds of textiles were chosen for each clothing item. To analyze the color characteristics of preferred textiles, spectral data were measured with spectrophotometer. By the results, color and color tone, value of L, a, b according to clothing item and season were compared. Chromaticity diagram was drawn, too. The results of this study are as following: 1. Color characteristics of shirts textile college student preferred for summer was PB color and p tone. The textile, in general, represented simple color that is close to achromatic color with light and soft shade. 2. The most preferred color of blouse textiles was G color and It, d tone. The color characteristics of blouse textiles represented stronger and more brilliant than those of shirts. 3. For slacks, colors of preferred summer textiles were mostly B, YR color and p, It.g, dk tone. Therefore, preferred textiles for slacks represented simple bluish or brownish color that is close to achromatic color with light or dark shade. 4. The most preferred color of skirt textiles were Y, R color and It tone. Skirt textiles had various colors compared to slacks. 5. College students generally prefer simple cold color that is close to achromatic color, because shirts and slacks have high frequency of wearing. In color tone, light and soft tone were preferred for shirts, and for slacks, they preferred light or dark tone. Comparatively, blouse and skirt which have low frequency of wearing represented various colors which contain more brilliant and stronger toned warm colors. 6. By the result of analyzing L, a, b value, shirts and blouse textiles showed higher L value than those of slacks and skirt. The textiles preferred by college students were generally close to achromatic color, because values of a, b were very low. This was confirmed with the result of chromaticity diagram. 7. In pattern of preferred textiles, solid textile were preferred mostly for shirt, blouse, skirt and slacks, and stripe pattern was preferred secondly.