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New Intra Coding Scheme for High-definition Video Coding (고화질 비디오 부호화를 위한 새로운 화면내 부호화 방법)

  • Heo, Jin;Ho, Yo-Sung
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.45 no.5
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    • pp.72-78
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    • 2008
  • Although the H.264 video coding scheme is popular, it is not efficient for high-definition (HD) video coding because the size of its macroblock is relatively small for the HD video resolution. In this paper, we propose a new intra coding scheme based on the enlarged macroblock size. For the luminance component, intra $4{\times}4$ prediction and intra $16{\times}16$ prediction in H.264 are scaled into intra $8{\times}8$ prediction and intra $32{\times}32$ prediction, respectively. For the chrominance components, intra $8{\times}8$ prediction is extended to intra $16{\times}16$ prediction. Along with the $8{\times}8$ basic coding block size, an $8{\times}8$ integer discrete cosine transform (DCT) is used. Experimental results show that the proposed algorithm improves coding efficiency of the intra coding for HD video: PSNR gain by 0.23dB and bit-rate reduction by 5.32% on average.

A Study on Pattern Inspection of LCD Using Color Compensation and Pattern Matching (색상보정 및 패턴 정합기법을 이용한 LCD 패턴검사에 관한 연구)

  • Ye, Soo-Young;Yoo, Choong-Woong;Nam, Ki-Gon
    • Journal of the Institute of Convergence Signal Processing
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    • v.7 no.4
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    • pp.161-168
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    • 2006
  • In this paper, we propose a method for the pattern inspection of LCD module using the color compensation and pattern matching. The pattern matching is generally used for the inspection method of LCD module at the industry. LCD module has many defections such as the brightness difference of the back light, the optic feature of liquid crystal, the difference of the light penetrated by driving LCD and the color difference by the lighting. The conventional method without the color compensation can not solve these defections and decreases the efficiency of inspecting LCD module. The method proposed to inspect defective badness through the pattern matching after it compensated color difference of the LCD occurred by the various causes. At first, it revises with setting by standard tone of color with the LCD pattern of the reference image. And It perform the preprocessing and pattern matching algorithm on the compensated image. In experiment, we confirmed that this algorithm is useful to detect some defections of LCD module. The proposed methods was easy to detect the faulty product.

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Changes in Quality Characteristics of Shark Meat (Dombaegi) during Salting Using Vacuum and Conventional Salting Methods (감압 및 절임방법에 따른 돔배기의 품질변화)

  • Kim, Do-Hoon;Lee, Shin-Ho;Youn, Kwang-Sup
    • Food Science and Preservation
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    • v.16 no.6
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    • pp.869-874
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    • 2009
  • We aimed to develop a new salting method to improve the quality of Dombaegi. The changes in quality characteristics of Dombaegi during salting using different salting methods (dry and brine salting) and salting pressures (vacuum and atmospheric pressure) were investigated. Moisture content was highest in Dombaegi prepared by brine salting under atmospheric pressure. Salt content was greater when salting was conducted under vacuum compared with atmospheric pressure. Water-holding capacity and water activity were higher under vacuum pressure than at atmospheric pressure and after dry salting compared with brine salting. Color change varied greatly when Dombaegi samples salted at atmospheric pressure and under vacuum were compared, and was affected more by dry salting than brine salting. Springiness was higher after salting under vacuum, and in dry conditions. The results showed that dry salting under vacuum provided better quality characteristics compared with other methods. Therefore, salting under vacuum was the optimal salting process.

Design of NTSC/PAL/SECAM Video Encoder for Mobile Device (모바일 기기를 위한 NTSC, PAL, SECAM 비디오 인코더의 설계)

  • Kim, Joo-Hyun;Yang, Hoon-Gee;Kang, Bong-Soon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.11C
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    • pp.1083-1090
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    • 2005
  • This paper presents the design of a video encoder for the device of need TV-OUT function. The designed video encoder satisfies the standard conditions of International Telecommunication Union-Radiocommunication (ITU-R) BT.470. ITU-R BT.470 can be classified as NTSC, PAL or SECAM. NTSC and PAL use Amplitude Modulation (AM) to transmit color difference signals and SECAM uses Frequency Modulation (FM). SECAM must have an antic-cloche filter but the filter recommended by ITU-R BT.470 is not easy to design due to sharpness of the frequency response. So formerly the filter was designed as analog. This paper proposes that the filter is designed as digital and the special quality of the filter is transformed easy to design. And the modulation method is modified to be identical with the result required at standard. The encoder can control power consumption by output mode to apply mobile phone, mobile devices, etc. The proposed encoder is experimentally demonstrated with ALTERA FPGA APEX20KE EP20K1000EBC652-3 device and SAMSUNG LCD-TV.

Intra MB Prediction Mode Decision Method for Fast MPEG-2 to H.264/AVC Transcoding (고속 MPEG-2-H.264/AVC 변 환부호화를 위한 화면내 MB 예측 모드 결정 기법)

  • Liu, Xingang;Yoo, Kook-Yeol
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.12C
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    • pp.1046-1054
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    • 2008
  • Since the high quality digital TV systems are broadly deployed in the market, the digital video contents will be edited and distributed in MPEG-2 MP@HL fonnat. Due to its impressive coding efficiency, the H.264/AVC codec has rapidly replaced the MPEG-4 SP codec for mobile digital video terminal with low quality. For the bro ad distribution of digitial video contents produced in MPEG-2 format, the MPEG-2 to H.264/AVC transcoding is highly necessary nowadays. In this paper, we propose a fast intra MB prediction mode decision method to reduce the computational complexity in the transcoding, which is the main bottleneck in the transcoders. The proposed method is based on the several relationships such as DCT coefficients and edge orientation, correlation between prediction directions in the $Intra16{\times}16$ and $Intra4{\times}4$ modes, correlation between edge-orientations of luminance an d chrominance components. The simulation results show that the proposed method can reduce the computational complexity upto 70% and 40%, compared with the cascaded transcoder and the well-known fast intraframe transc oder, respectively.

Adaptive Intra Prediction Method using Modified Cubic-function and DCT-IF (변형된 3차 함수와 DCT-IF를 이용한 적응적 화면내 예측 방법)

  • Lee, Han-Sik;Lee, Ju-Ock;Moon, Joo-Hee
    • Journal of Broadcast Engineering
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    • v.17 no.5
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    • pp.756-764
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    • 2012
  • In current HEVC, prediction pixels are finally calculated by linear-function interpolation on two reference pixels. It is hard to expect good performance on the case of occurring large difference between two reference pixels. This paper decides more accurate prediction pixel values than current HEVC using linear function. While existing prediction process only uses two reference pixels, proposed method uses DCT-IF. DCT-IF analyses frequency characteristics of more than two reference pixels in frequency domain. And proposed method calculates prediction value adaptively by using linear-function, DCT-IF and cubic-function to decide more accurate interpolation value than to only use linear function. Cubic-function has a steep slope than linear-function. So, using cubic-function is utilized on edge in prediction unit. The complexity of encoder and decoder in HM6.0 has increased 3% and 1%, respectively. BD-rate has decreased 0.4% in luma signal Y, 0.3% in chroma signal U and 0.3% in chroma signal V in average. Through this experiment, proposed adaptive intra prediction method using DCT-IF and cubic-function shows increased performance than HM6.0.

Image Processing System for Color Analysis of Food (식품의 색채 분석을 위한 영상 처리 시스템)

  • Kim, Kyung-Man;Seo, Dong-Wook;Chun, Jae-Kun
    • Korean Journal of Food Science and Technology
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    • v.28 no.4
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    • pp.786-789
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    • 1996
  • An image processing system was built to evaluate the color properties of apple and meat. The system consisted of video camera, video card, 32 bit microcomputer and an optical illuminator. The operating software was developed to carry out capturing, analyzing, displaying and storing of the 8 bit digitized images of food. The images of apples at various maturing stages were investigated to obtain the color histogram of R, G, B and Hunter value. RGB histogram showed a major difference in G value, 35.01, the minor change in R value, 6.16, and the negligible difference in B value. The image of beef cut was separated into two parts, fat and lean tissue, by applying threshold value method based on the digital value of color. The threshold value for fat was over 240 and for lean under 230 in R value, respectively. The resulting non fat image showed 2% decreased color difference value, ${\Delta}E$, than whole meat cut.

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Intra Prediction Offset Compensation for Improving Video Coding Efficiency (영상 부호화 효율 향상을 위한 화면내 예측 오프셋 보상)

  • Lim, Sung-Chang;Lee, Ha-Hyun;Choi, Hae-Chul;Jeong, Se-Yoon;Kim, Jong-Ho;Choi, Jin-Soo
    • Journal of Broadcast Engineering
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    • v.14 no.6
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    • pp.749-768
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    • 2009
  • In this paper, an intra prediction offset compensation method is proposed to improve intra prediction in H.264/AVC. In H.264/AVC, intra prediction based on various directions improves the coding efficiency by removing spatial correlation between neighboring blocks. In details, neighboring pixels in reconstructed block can be used as intra reference block for the current block to be coded when intra prediction method is used. In order to reduce further the prediction error of the intra reference block, the proposed method introduces an intra prediction offset which is determined in the sense of the rate-distortion optimization and is added to the conventional intra prediction block. Besides the intra prediction offset compensation, the coefficient thresholding method which is used for inter coding in JM 11.0, is used for chroma component in intra block, which leads the improvement of the luma coding efficiency of the proposed method. In experiments, we show that the proposed method achieves average 2.45% in High Profile condition and maximum 4.41% of bitrate reduction relative to JM 11.0.

Implementation on the Urine Analysis System using Color Correction and Chromaticity Coordinates Transform Methods (색 보정 및 색 좌표 변환 기법을 이용한 요분석 시스템의 구현)

  • 김기련;예수영;손정만;김철한;정도운;이승진;장용훈;전계록
    • Journal of Biomedical Engineering Research
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    • v.24 no.3
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    • pp.183-192
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    • 2003
  • A transformation methode of the chromaticity coordinates was proposed to calibrate the measured data obtained by a urine analysis system which implemented in our previous study. Generally. the reacted color of a reagent strip by urine analysis system often exhibit the color distortions due to nonlinear characteristics of the various devices that is the optic module mechanism. hardware, and surround circumstance. A color correction method for minimizing the color distortion play a few role in maintaining high accuracy and reproduction of the urine analysis system. In this work, we used the compensation method such as the shading correction, the characteristic curve extraction of RGB color by means of third order spline interpolation, and linear transformation using a reference color. In addition, 1931 CIE XYZ color space was used to compensate the color of the measured data by a standard reference system as colorimeter. A compensation matrix was obtained so that the output values of the urine analysis system is nearly equal to that of a standard reference system for identical color sample. Color correction obtained by a urine analysis system which implemented in our previous study exhibited a good color accuracy when it was compared with the reference data. Observed result from an experiments on ten items or a urinalysis strip that color difference or between two urine analysis system was 1.28.

Chromatic adaptation model for the variations of the luminance of the same chromaticity illuminants (동일 색도 광원의 휘도 변화에 따른 색 순응 모델)

  • Kim Eun-Su;Jang Soo-Wook;Lee Sung-Hak;Sohng Kyu-lk
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.42 no.4 s.304
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    • pp.31-38
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    • 2005
  • In this paper, we propose the chromatic adaptation models (CAM) for the variations of the luminance levels. A chromatic adaptation model, CAM$\Delta$Y , is proposed according to the change of luminance level under the same illuminants. The proposed model is obtained by the transform the test colors of the high luminance into the corresponding colors of the low luminance. In the proposed model, the optimal coefficients are obtained from the corresponding colors data of the Breneman's experiments. In the experimental results, we confined that the chromaticity errors, $\Delta$u'v', between the predicted colors by the proposed model and the corresponding colors of the Breneman's experiments are 0.004 in u'v' chromaticity coordinates. The prediction performance of the proposed model is excellent because this error is the threshold value that two adjacent color patches can be distinguished. Additionally, we also propose equal-whiteness CCT curves (EWCs) by CAM$\Delta$Y according to the luminance levels of the surround viewing conditions. And the proposed EWCs can be used as the theoretical standard which determines the reference white of the color display devices.