1-5hit |
Tae-Wuk BAE Sung-Hak LEE Jung-Wook LEE Kyu-Ik SOHNG
This paper proposes a new auto flesh tone balance algorithm for the picture that is taken for people. In this paper, the basis of auto white balance (AWB) is human face in photo. For experiment, the transfer characteristic of camera image sensor is analyzed and the camera output RGB is calculated by measuring the average face chromaticity under standard illuminant. For the face region taken under unknown illuminant, the proposed algorithm makes RGB output rate of face region become its rate of standard face color. For this, it adjusts the R and B channel and performs the chromaticity correction. Algorithm is applied to the light skin color (average face color) in Macbeth color chart and average color of various face colors that are actually measured.
Slit-Mura defect is a notorious yield flaw of color filters. In this study, an innovative non-contact in-line optical inspection method is developed to detect low contrast slit Mura through quantitative measurements by a spectrometer. Using the features of either thickness or chromaticity profiles across a slit Mura, a thickness difference from 21 nm to 41 nm of color filters can be differentiated accurately. Thus, the quality of color filters can be accessed in-line during the manufacturing process TFT-LCDs.
Sung-Hak LEE Jong-Hyub LEE Kyu-Ik SOHNG
An image sensor for a use of colorimeter is characterized based on the CIE standard colorimetric observer. We use the method of least squares to derive a colorimetric characterization matrix between RGB output signals and CIE XYZ tristimulus values. This paper proposes an adaptive measuring method to obtain the chromaticity of colored scenes and illumination through a 33 camera transfer matrix under a certain illuminant. Camera RGB outputs, sensor status values, and photoelectric characteristic are used to obtain the chromaticity. Experimental results show that the proposed method is valid in the measuring performance.
Aryuanto SOETEDJO Koichi YAMADA
This paper describes a new color segmentation based on a normalized RGB chromaticity diagram for face detection. Face skin is extracted from color images using a coarse skin region with fixed boundaries followed by a fine skin region with variable boundaries. Two newly developed histograms that have prominent peaks of skin color and non-skin colors are employed to adjust the boundaries of the skin region. The proposed approach does not need a skin color model, which depends on a specific camera parameter and is usually limited to a particular environment condition, and no sample images are required. The experimental results using color face images of various races under varying lighting conditions and complex backgrounds, obtained from four different resources on the Internet, show a high detection rate of 87%. The results of the detection rate and computation time are comparable to the well known real-time face detection method proposed by Viola-Jones [11],[12].
Hiroyuki FUJII Hidehiro SAKURAI Kazuyasu TANI Lisheng MAO Kenichiro WAKISAKA Toshikazu HIRAO
Newly designed cyclometalated iridium phosphors bearing 2,3-diphenylquinoxalines were characterized to provide highly efficient and vivid-red emitting materials for electrophosphorescent organic light-emitting devices. Excellent quantum efficiencies for photoluminescence (PL) within a range 50-79% were observed in dichloromethane solutions at room temperature. A greatly improved PL decay lifetime of 1.1 µsec was also observed in CBP coevaporated film. Luminescence peak wavelengths of the phosphors lay within a preferable range 653-675 nm in evaporated films. The most vivid-red electroluminescence with 1931 CIE chromaticity coordinates of (x=0.70, y=0.28) was successfully attained.