• Title/Summary/Keyword: Gray difference

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Recovering the Colors of Objects from Multiple Near-IR Images

  • Kim, Ari;Oh, In-Hoo;Kim, Hong-Suk;Park, Seung-Ok;Park, Youngsik
    • Journal of the Optical Society of Korea
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    • v.19 no.1
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    • pp.102-111
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    • 2015
  • This paper proposes an algorithm for recovering the colors of objects from multiple near-infrared (near-IR) images. The International Commission on Illumination (CIE) color coordinates of objects are recovered from a series of gray images captured under multiple spectral near-IR illuminations using polynomial regression. The feasibility of the proposed algorithm is tested experimentally by using 24 color patches of the Color Rendition Chart. The experimental apparatus is composed of a monochrome digital camera without an IR cut-off filter and a custom-designed LED illuminator emitting multiple spectral near-IR illuminations, with peak wavelengths near the red edge of the visible band, namely at 700, 740, 780, and 860 nm. The average color difference between the original and the recovered colors for all 24 patches was found to be 11.1. However, if some particular patches with high value are disregarded, the average color difference is reduced to 4.2, and this value is within the acceptability tolerance for complex image on the display.

Fast Algorithm for Intra Prediction of HEVC Using Adaptive Decision Trees

  • Zheng, Xing;Zhao, Yao;Bai, Huihui;Lin, Chunyu
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.7
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    • pp.3286-3300
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    • 2016
  • High Efficiency Video Coding (HEVC) Standard, as the latest coding standard, introduces satisfying compression structures with respect to its predecessor Advanced Video Coding (H.264/AVC). The new coding standard can offer improved encoding performance compared with H.264/AVC. However, it also leads to enormous computational complexity that makes it considerably difficult to be implemented in real time application. In this paper, based on machine learning, a fast partitioning method is proposed, which can search for the best splitting structures for Intra-Prediction. In view of the video texture characteristics, we choose the entropy of Gray-Scale Difference Statistics (GDS) and the minimum of Sum of Absolute Transformed Difference (SATD) as two important features, which can make a balance between the computation complexity and classification performance. According to the selected features, adaptive decision trees can be built for the Coding Units (CU) with different size by offline training. Furthermore, by this way, the partition of CUs can be resolved as a binary classification problem. Experimental results have shown that the proposed algorithm can save over 34% encoding time on average, with a negligible Bjontegaard Delta (BD)-rate increase.

AN EXPERIMENTAL STUDY ON THE TOOTH ROOT RESORPTION FOR DIGITAL RADIOGRAPHY (디지털 방사선 촬영술을 이용한 치근 흡수 판독에 관한 실험적 연구)

  • Oh Phill-Gyo;Kim Jae-Duk
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.25 no.2
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    • pp.375-387
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    • 1995
  • The purpose of this study was to quantitatively evaluated experimental tooth root resorption for digital radiography. For this study, experimentally three root sites were used, and radiograms were taken with standardized apparatus. Digital imaging system were consisted of NEC PC-980l(computer), TRINITRON(monitor), SONY XC-711 CCD camera. The display monitor had a resolution of 512X512 pixels. The obtained results were as follows: 1. In the difference of the four X-ray film of the contrast correction, the contrast difference was one gray scale variation at mean value. 2. Viewing of the view box of the periapical radiographs, experimental tooth root resorption of the periapical area of the first premolar, middle of mesial surface of the first molar mesial root, middle of lingual surface of the first molar distal root were recognized by increased diameter. 3. On the analysis by histogram, the periapical area of the first premolar, the middle of mesial surface of the first molar mesial root were each recognized tooth root resorption of the 5,6,7 pixel, 2,4,5 pixel by increased diameter. 4. On the analysis by histogram, the middle of lingual surface of the first molar distal root was each recognized tooth root resorption of the none, 3,6 pixel by increased diameter.

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Efficient Human body tracking Using Similarity Of Histogram Of Intensity and Hue Local Area (국부 영역의 명도와 색상 히스토그램 유사도를 이용한 인체 추적)

  • Kwak, Nae-Joung;Song, Teuk-Seob
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2016.10a
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    • pp.149-152
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    • 2016
  • In this paper, we propose an algorithm to track human body of input video from a single camera. The proposed method gets the difference image between gray image of input image and one of background image and also the difference image between hue image of input image and one of background image. Then we combine the results, splits foreground and background and detect human body objects. Then each object is numbered and is tracked. The proposed method tracks each object using the intensity and hue histogram of local area in objects. The proposed method is applied to video from a camera and tracked well the hided objects and the overlapped objects.

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Response of Gray Rock Cod to the Colored Lights (색광에 대한 볼낙의 반응)

  • YANG Yong-Rhim
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.16 no.4
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    • pp.330-334
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    • 1983
  • The author carried out an experiment to find out the response of gray rock cod, Sebastes inermis (Cuvier et Valenciennes) to the color light. The experimental tank ($360L{\times}50W{\times}55H\;cm$) was set up in a dark room. Six longitudinal sections with 60 cm intervals are marked in the tank to observe the location of the fish. Water depth in the tank was kept 50 cm level. Light bulbs of 20W at the both ends of the tank projected the light horizontally into the tank. Two different colored filters were selected from four colors of red, blue, yellow, and white, and they were placed in front of the light bulbs to make different colors of light. Light intensity were controlled by use of auxiliary filters intercepted between the bulb and the filter. The fishes were acclimatized in the dark for 50 minutes before they were employed in the experiment. Upon turning on the light, the number of fish in each section was counted 40 times in 30 second intervals, and the mean of the number of fish in each section was given as the gathering rate of the fish. The colors favourited by the fish was found in the order of white, blue, yellow and red. The gathering rate of fish on illumination period was small and comparatively fluctuated with stability. The difference of the gathering rates on two different colors of light was much greater, regardless of illumination period, in day time than in night time.

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Sex Differences in Cerebellar Structure of Healthy Adults (정상 성인에서 남녀의 소뇌 구조 차이)

  • Kim, Ji-Hyun H.;Bae, Su-Jin;Ryu, Keun-Taik;Kang, Min-Seong;Lim, Soo-Mee;Lee, Sun-Ho;Lee, So-Jin;Ko, Eun;Jeong, Do-Un
    • Korean Journal of Biological Psychiatry
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    • v.19 no.2
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    • pp.77-83
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    • 2012
  • Objectives : Although there have been studies that examine sex differences of the brain structures using magnetic resonance imaging, studies that specifically investigate cerebellar structural differences between men and women are scarce. The purpose of current study was to examine sex differences in structures of the cerebellum using cerebellar template and cerebellum analysis methods. Methods : Sixteen men and twenty women were included in the study. A MATLAB based program (MathWorks, Natick, MA, USA), Statistical Parametric Mapping 5 (SPM5) using the spatially unbiased infra-tentorial atlas template (SUIT) as the cerebellum template, was used to analyze the brain imaging data. Results : There was no significant difference in age between men (mean age=28.1) and women (mean age=27.2). Men showed higher gray matter density than women in two left cerebellar areas including the clusters in the lobules IV and V (a cluster located across the lobules IV and V), and the lobule VIIIb (lobules IV and V, t=4.75, p<0.001 ; lobule VIIIb, t=3.08, p=0.004). Conclusions : The current study found differences in cerebellar gray matter density between men and women. The current study holds its significance for applying the template specifically developed for the analysis of cerebellum.

An Adaptive Thresholding of the Nonuniformly Contrasted Images by Using Local Contrast Enhancement and Bilinear Interpolation (국소 영역별 대비 개선과 쌍선형 보간에 의한 불균등 대비 영상의 효율적 적응 이진화)

  • Jeong, Dong-Hyun;Cho, Sang-Hyun;Choi, Heung-Moon
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.36S no.12
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    • pp.51-57
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    • 1999
  • In this paper, an adaptive thresholding of the nonuniformly contrasted images is proposed through using the contrast pre-enhancement of the local regions and the bilinear interpolation between the local threshold values. The nonuniformly contrasted image is decomposed into 9${\times}$9 sized local regions, and the contrast is enhanced by intensifying the gray level difference of each low contrasted or blurred region. Optimal threshold values are obtained by iterative method from the gray level distribution of each contrast-enhanced local region. Discontinuities are reduced at the region of interest or at the characters by using bilinear interpolation between the neighboring threshold surfaces. Character recognition experiments are conducted using backpropagation neural network on the characters extracted from the nonuniformly contrasted document, PCB, and wafer images binarized through using the proposed thresholding and the conventional thresholding methods, and the results prove the relative effectiveness of the proposed scheme.

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Flexible Background-Texture Analysis for Coronary Artery Extraction Based on Digital Subtraction Angiography (유동적인 배경 텍스쳐 분석을 통한 DSA 기반의 관상동맥 검출)

  • Park Sung-Ho;Lee Joong-Jae;Lee Geun-Soo;Kim Gye-Young
    • The KIPS Transactions:PartB
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    • v.12B no.5 s.101
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    • pp.543-552
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    • 2005
  • This paper proposes the extraction of coronary arteries based on DSA(Digital Subtraction Angiography) through a texture analysis of background in the angiography. DSA is a well established modality for the visualization of coronary arteries. DSA involves the subtraction of a mask image - an image of the heart before injection of contrast medium - from live image. However, this technique is sensitive to the movement of background and can result to a wrong detection by the variance of background gray-level intensity between two images. Therefore, this paper solves a structural problem resulted from a background movement bV selecting an image which has the least difference of movement through an analysis of the similarity of background texture and proposes a method to extract only the blood vessel efficiently through local gray-level correction of the selected image. Using the coronary angiogram of 5 patients clinical data, we proved that the proposed method has the lower false-detection rate, approximately $2\%$, and the higher accuracy than the existing methods.

Study on the Scanimation Expression Using Color Scheme (색상 배색을 이용한 Scanimation 표현방법 연구)

  • Lee, Yu-Seop;Chung, Jean-Hun
    • Journal of Digital Convergence
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    • v.14 no.12
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    • pp.451-456
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    • 2016
  • Scanimation is utilized in various fields due to its simple and easy basic principle, whereas mostly it is expressed in gray scale, and the cases of expressing with color is rare. This research classified scanimation into form change of the images with no connectivity, continuous motion of the images with connectivity, and optical illusion with continuity along with visualization effect based on the advanced research and utilization case, and conducted a comparative analysis of scanimation per type applied with color scheme by color difference based on PCCS(Practical Color Co-ordinate System) system. Based on this research, the researcher intended to suggest various direction and expressive method of scanimation using color, expecting the research result could be a valuable reference for the researches utilizing scanimation, henceforth.

Effective Gray-white Matter Segmentation Method based on Physical Contrast Enhancement in an MR Brain Images (MR 뇌 영상에서 물리기반 영상 개선 작업을 통한 효율적인 회백질 경계 검출 방법)

  • Eun, Sung-Jong;Whangbo, Taeg-Keun
    • Journal of Digital Contents Society
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    • v.14 no.2
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    • pp.275-282
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    • 2013
  • In medical image processing field, object recognition is usually carried out by computerized processing of various input information such as brightness, shape, and pattern. If the information mentioned does not make sense, however, many limitations could occur with object recognition during computer processing. Therefore, this paper suggests effective object recognition method based on the magnetic resonance (MR) theory to resolve the basic limitations in computer processing. We propose the efficient method of robust gray-white matter segmentation by texture analysis through the Susceptibility Weighted Imaging (SWI) for contrast enhancement. As a result, an average area difference of 5.2%, which was higher than the accuracy of conventional region segmentation algorithm, was obtained.