• Journal of Korea Multimedia Society
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• v.4 no.4
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• pp.316-323
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• 2001

Gamut mapping is a technique that acts on cross-media color reproduction to transform a color between devices for the purpose of enhancing the appearance or preserving the appearance of an image. Gamut mapping essentially produces color conversion error which depends on the gamut mapping method, source and destination devices, and sample points for gamut modeling. For color space conversion between monitor colors and printer colors, empirical representation using sample measurements is currently widely utilized. Color samples are uniformly selected in the device space such as CMY or RGB, represented as color patches, and then measured. However, in the case of printer, these color samples are not evenly distributed inside the printer gamut and the color conversion error is increased. Accordingly, this paper introduces a equally distributed color sampling method in CIELAB space, a device- independent color space, to reduce color conversion error, and the performance is analyzed via color space conversion experiments using three-dimensional interpolation.

• Proceedings of the IEEK Conference
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• summer
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• pp.122-127
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• 2004

The color gamut mapping method that is used for enhancing the color reproduction quality between PC monitor and printer devices is adopted for display quality enhancement. The high definition display devices operate at the clock speed of around $70\;MHz\;\sim\;150\;MHz$ and permit several nano seconds for real-time processing. Thus, the concept of three-dimensional reduced resolution look-up table is used. The required hardware can be greatly reduced by look-up table resolution adjustment. The proposed hardware architecture is successfully implemented in ASIC and also successfully adopted in display quality enhancement purposes.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.693-694
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• 2006

The high definition digital TV display devices need real-time gamut mapping. This paper proposes a gamut mapping algorithm that used three dimensional reduced resolution look up table and tetrahedral interpolation for real-time processing. The proposed hardware architecture is successfully implemented in FPGA and ASIC.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.44 no.1
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• pp.56-63
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• 2007

A color gamut mapping has been known to be one of promising methods to enhance display quality of various types of color display device. However, it is required to handle this mapping in real time for display or digital TV application. If carefully arranged, the tetrahedral interpolation can be computed with simpler operations compared to a cubic interpolation in the conventional reduced resolution look-up table which is devised to process the gamut mapping in real time. Based on the tetrahedral interpolation, a new type hardware architecture for real-time gamut mapping is proposed in this paper. The proposed hardware architecture shows better processing speed and reduces the hardware cost.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.36S no.1
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• pp.38-50
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• 1999

Currently many devices reproduce electronic images in the various ways. However the color that is reproduced in any device is different from the original color due to the difference in the gamut between devices. In this paper, an image dependent gamut mapping method is proposed. This method clips the chroma with compensating for the change of lightness caused by the lightness scaling. The anchor point, which is the center point in the mapping, is set as a lower point by the proposed method than a point by the conventional mapping method. This reduces the color difference between point. In addition, to heighten the color contrast on the constant hue, the different two mapping methods are applied to the printer gamut which is divided in two region, bright region and dark region. Consequently, the printer output image was highly consistent with the corresponding monitor image.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.43 no.1 s.307
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• pp.45-54
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• 2006

This paper proposed color matching technique, including display characterization, chromatic adaptation model, and gamut mapping and extension, to generate consistent colors for the same input signal in each display device. It is necessary to characterize the relationship between input and output colors for display device, to apply chromatic adaptation model considering the difference of reference white, and to compensate for the gamut which display devices can represent for reproducing consistent colors on DTV display devices. In this paper, 9 channel-independent GOG model, which is improved from conventional 3 channel GOG(gain, offset gamma) model, is used to consider channel interaction and enhance the modeling accuracy. Then, the input images have to be adjusted to compensate for the limited gamut of each display device. We proposed the gamut mapping and extension method, preserving lightness and hue of an original image and enhancing the saturation of an original image in xy chromaticity diagram. Since the hmm visual system is more sensitive to lightness and hue, these values are maintained as the values of input signal, and the enhancement of saturation is changed to the ratio of input and output gamut. Also the xy chromaticity diagram is effective to reduce the complexity of establishing gamut boundary and the process of reproducing moving-pictures in DTV display devices. As a result, reproducing accurate colors can be implemented when the proposed method is applied to LCD and PDP display devices

• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.6
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• pp.137-146
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• 1998

Recently many devices print electronic images in a variety of ways. The reproduced color, however, is different from the original color because of the difference of hardware characteristics. To maintain device independent color, gamut mapping method is proposed. The proposed color gamut mapping uses nonlinear intensity mapping and clipping for saturation mapping on HSI color space. In the dithering operation, expanded nonlinear ordered dithering and modified error diffusion are proposed. The proposed ordered dithering uses expanded nonlinear quantization which considers overlapping phenomena of neighbored printing dots. In the modified error diffusion, quantization errors to be diffused are adjusted to improve both image blur and color change produced in the error diffusion. So, the printed image is similar to the image of monitor. Our results indicate that proposed algorithm can produce high quality image in the low bit color devices.

• Proceedings of the Korean Printing Society Conference
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• 2001.06a
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• pp.78-91
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• 2001

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1584-1587
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• 2005

Although the picture quality of today's displays is very good already, a continuous improvement is desirable as the new larger display sizes increase the visibility of artifacts. A contributing factor for picture quality enhancement through smart video processing and algorithm design is the information gathered from video statistics. Interesting parameters gathered from video statistics are e.g. the image- and display load, the usage of the color gamut, the estimated power consumption and the occurrence of static image parts. Examples of applications that can benefit from video statistics are power calculations, color gamut mapping algorithms, dynamic backlight control for LCD panels and LED backlights for LCD panels.

• Proceedings of the IEEK Conference
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• 2003.07e
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• pp.1779-1782
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• 2003

본 논문에서는 새로운 색역폭(color gamut) 매핑 방법을 이용하여 디지털 TV 디스플레이 장치의 화질을 개선하는 방법을 제안하였다. 기존에 실시간 적응이 어렵던 색역폭 매핑 방법을 실시간으로 처리하기 위한 하드웨어 구조를 제안하였으며 이를 통하여 수 나노 초 단위의 처리 속도가 필요한 디지털 TV 의 디스플레이 장치에 성공적으로 적용이 가능하였다. 또한 제안된 하드웨어 구조는 필요에 따라 색역폭 매핑 해상도의 조절이 가능하여 해상도 및 하드웨어 구현 비용을 적절히 조절할 수 있는 장점이 있다.