• Title, Summary, Keyword: Brightness

Search Result 2,843, Processing Time 0.05 seconds

MIXED BRIGHTNESS-INTEGRALS OF CONVEX BODIES

  • Li, Ni;Zhu, Baocheng
    • Journal of the Korean Mathematical Society
    • /
    • v.47 no.5
    • /
    • pp.935-945
    • /
    • 2010
  • The mixed width-integrals of convex bodies are defined by E. Lutwak. In this paper, the mixed brightness-integrals of convex bodies are defined. An inequality is established for the mixed brightness-integrals analogous to the Fenchel-Aleksandrov inequality for the mixed volumes. An isoperimetric inequality (involving the mixed brightness-integrals) is presented which generalizes an inequality recently obtained by Chakerian and Heil. Strengthened version of this general inequality is obtained by introducing indexed mixed brightness-integrals.

Controlling Brightness Compensation of Full Color LED Vision (천연색 LED 정보표시 시스템의 휘도보정 제어장치)

  • Hwang, Hyun-Hwa;Yim, Hyung-Kun;Park, Jung-Hwan;Lee, Jong-Ha
    • Proceedings of the IEEK Conference
    • /
    • /
    • pp.1291-1296
    • /
    • 2005
  • In this paper, we prevent a display quality drop for image of characteristics brightness ununiformity depend on LED use to LED vision. It is about that method also a control system development equipped with brightness compensation function of LED vision which is done easily for LED set up of LED vision. Generally, It is calculate driving current value is attended by each brightness to brightness characteristics mathematical function establish by "Y=aX+b", When is doing brightness value for "Y", driving current value for "X", brightness compensation value by using time for "b", characteristics value for "a" ground with characteristics curve of LED. So much, First It is create brightness data of each pixel take a photograph red, green and blue of LED vision. Second It is get average error about each pixel which get average brightness value of entire. Last, It is handle a complicated for about gradationally regulation to color and brightness of image send to LED vision. Also It raise the whole average brightness value of vision adjust for "b" value to solve brightness drop problem of LED using the long time.

  • PDF

Brightness Function on TV Viewing Condition (TV 시청 조건에서의 Brightness Function)

  • 최성호;김희철;장수욱;김은수;한찬호;송규익
    • Proceedings of the IEEK Conference
    • /
    • /
    • pp.2403-2406
    • /
    • 2003
  • When viewing images, the relative luminance of the surround has a profound impact on the apparent contrast of the image. The dark surround causes the image elements to appear lighter than those viewed in an illuminated surround. For this reason, it is worthwhile to briefly review the general results of brightness sealing under a various viewing condition. Two of the most often cited parers on the topic of brightness scaling are Stevens-stevens and Bartleson-Breneman's function. There are, however, significant differences between the perceptual functions for simple-field and complex-field viewing. In this paper, we research the relationship between Steven's power law and Bartleson-Breneman's function. We present an appropriate brightness perception function due to TV system viewing conditions. Highlight luminance peak and absolute brightness threshold value in various adaptation levels are obtained from the proposed brightness function . Also, the luminance value of black level to produce the same contrast ratio with variety of display highlight luminance peak is obtained from the proposed brightness function.

  • PDF

Contrast Image Enhancement Using Multi-Histogram Equalization

  • Phanthuna, Nattapong;cheevasuwit, Fusak
    • International Journal of Advanced Culture Technology
    • /
    • v.3 no.2
    • /
    • pp.161-170
    • /
    • 2015
  • Mean separated histogram equalization in order to preserve the original mean brightness has been proposed. To provide the minimum mean brightness error after the histogram modification, the input image's histogram is successively divided by the factor of 2 until the mean brightness error is satisfied the defined threshold. Then each divided group or sub-histogram will be independently equalized based on the proportional input mean. To provide the overall minimum mean brightness error, each group will be controlled by adding some certain pixels from the adjacent grey level of the next group for giving its mean near by the corresponding the divided mean. However, it still exists some little error which will be put into the next adjacent group. By successive dividing the original histogram, we found that the absolute mean brightness error is gradually decreased when the number of group is increased. Therefore, the error threshold is assigned in order to automatically dividing the original histogram for obtaining the desired absolute mean brightness error (AMBE). This process will be applied to the color image by treating each color independently.

Approximate and Three-Dimensional Modeling of Brightness Levels in Interior Spaces by Using Artificial Neural Networks

  • Sahin, Mustafa;Oguz, Yuksel;Buyuktumturk, Fuat
    • Journal of Electrical Engineering and Technology
    • /
    • v.10 no.4
    • /
    • pp.1822-1829
    • /
    • 2015
  • In this study, artificial neural networks were used to determine the intensity of brightness in interior spaces. The illumination elements to illuminate indoor spaces were considered, not individually, but as a system. So, during the planned maintenance periods of an illumination system, after its design and installation, simple brightness level measurements must be taken. For a three-dimensional evaluation of the brightness level in indoor spaces in a speedy and accurate manner, the obtained brightness level measurement results and artificial neural network model were used. Upon estimation of the most suitable brightness level for indoor spaces by using the artificial neutral network model, the energy demands required by the illumination elements decreased. Consequently, in this study, with estimations of brightness levels, the extent to which the artificial neutral networks become successful was observed and more correct results have been obtained in terms of both economy and usage.

Change of Intrinsic Brightness Temperatures of Compact Radio Jets

  • Lee, Sang-Sung
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.39 no.2
    • /
    • pp.57.1-57.1
    • /
    • 2014
  • We present results of our investigation of intrinsic brightness temperatures of compact radio jets at radio frequencies. The intrinsic brightness temperatures of about 100 compact radio jets at 2, 5, 8, 15, and 86 GHz are estimated based on large VLBI surveys conducted in 2001-2003 (or in 1996 for the 5 GHz sample). The multi-freqeuncy intrinsic brightness temperatures of the sample of the jets are determined with a statistical method relating the observed brightness temperatures with the maximal apparent jet speed, assuming one representative intrinsic brightness temperature for the sample at each observing frequency. With investigating the observed brightness temperatures at 15 GHz in multiple epochs, we found that the determination of the intrinsc brightness temperature for our sample is affected by variability of individual jets in flux density at the time scales of a few years. This implies an importance of contemporaneity of the multi-frequency VLBI observations for the statistical method. Since our analysis is based on the VLBI observations conducted in 2001-2003, the results are less affected by the flux density variability. We found that the intrinsic brightness temperature $T_0$ increases as $T_0{\propto}{\nu}^{\epsilon}$ with ${\epsilon}{\approx}0.7$ below a critical frequency ${\nu}_c{\approx}10GHz$ where energy losses begin to dominate the emission, and above the critical frequency, $T_0$ decreases with ${\epsilon}{\approx}-1.2$ supporting for the decelerating jet model.

  • PDF

A Study on Improving Brightness Values for Real Representations of Material Images in Lightscape (Lightscape에서의 사실적 재질 이미지 표현을 위한 Brightness 수치 개선에 관한 연구)

  • Chang, Jun-Ho;Park, Ji-Ae;Choi, An-Seop
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.21 no.2
    • /
    • pp.1-8
    • /
    • 2007
  • This study is to generate optimal values of brightness and achieve more realistic images by varying such values according to individual materials in order to create better quality simulation images using Lightscape. Because there are discolorations of materials by adding the radiation of luminaires to that of daylight during the daytime, when low brightness values are inputted in case of daytime, the results are founded that images of materials can be seen much similar with real images. And in most of the materials, when low values in the daytime and high values in the nighttime are inputted this study verifies that the realest simulation images can be obtained using Lightscape, because the RGB data of simulation images are almost similar with that of real materials.

The Impact of Brightness, Polarity, and Hue Difference on Legibility and Emotional Effect of Word in Visual Display (시각디스플레이에서 단어와 배경간의 밝기, 대비부호, 색상차이에 따른 가독성 및 감성효과)

  • Jung, Hye-Heon;Cho, Kyung-Ja;Han, Kwang-Hee
    • Korean Journal of Cognitive Science
    • /
    • v.17 no.4
    • /
    • pp.337-356
    • /
    • 2006
  • This research was conducted to see the impact of brightness, polarity, and hue diference on legibility and emotional effcts of the word. In the experiment 1, stimuli with three levels of brightness difference and two-typed polarity were used. The results showed that legibility, aesthetics, and preference increased with increasing brightness difference. In the experiment 2, the same stimuli if experiment 1 included four hues: red, green, blue, yellow. As a result, the effects of brightness and polarity and the interaction effect of brightness and polarity on legibility were significant. Also, the effects of brightness, polarity, and hue and the interaction effect of brightness and hue on aesthetics and preference were significant. These results showed that legibility, aesthetics, and preference increased with increasing brightness difference of word and background and positive polarity was better than negative. Aesthetics and preference rating increased according to the following order: red, blue, green, yellow. In addition, the interaction effect of brightness and polarity on legibility was because reaction time of negative polarity was longer than positive at the small brightness difference condition. The interaction effect of brightness and hue on aesthetics and preference ws because the aesthetics rating of hue at the large brightness difference condition had significant difference compared with small brightness difference. In the experiment 3, participants rated text designs and simple color stimuli with 18 emotional adjectives to see the similarity of their emotion. The conclusion was that to reflect the subjective feelings of a rotor on the text design, it would be appropriate to use the rotor on background of the text design.

  • PDF

Analysis of Eye Response to Low Brightness 3D Displays and Increase Brightness in 3D RPTV using Long Life, High Power DPR System

  • Li, Kenneth
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • /
    • pp.763-764
    • /
    • 2008
  • 3D displays requires multiplexing of left and right pictures on the same screen so that they can be viewed independently by the view using various schemes, including LCD shutters, polarizers, narrow band filters, and lenticular lenses on the screen. All these methods reduce the effective screen brightness by as much as 10X. The eye responses to the lower brightness are analyzed and found to compensate partially giving a lower perceived brightness. This paper presents such eye response analysis and a low cost approach to increasing brightness in a RPTV using the long life DPR system, increasing the screen brightness by over 2.5 times, while maintaining acceptable lamp lifetime.

  • PDF