• Title/Summary/Keyword: adjusting brightness

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Image Quality Enhancement by Using Logistic Equalization Function (로지스틱 평활화 함수에 의한 영상의 화질개선)

  • Cho, Yong-Hyun
    • Journal of the Korean Institute of Intelligent Systems
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    • v.20 no.1
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    • pp.30-35
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    • 2010
  • This paper presents a quality enhancement of images by using a histogram equalization based on the symmetric logistic function. The histogram equalization is a simple and effective spatial processing method that it enhances the quality by adjusting the brightness of image. The logistic function that is a sigmoidal nonlinear transformation function, is applied to non-linearly enhance the brightness of the image according to its intensity level frequency. We propose a flexible and symmetrical logistic function by only using the intensity with maximum frequency in an histogram and the total number of pixels. The proposed function decreases the computation load of an exponential function in the traditional logistic function. The proposed method has been applied for equalizing 5 images with a different resolution and histogram distribution. The experimental results show that the proposed method has the superior enhancement performances compared with the source images and the traditional global histogram equalization, respectively.

Image Recognition Based on Nonlinear Equalization and Multidimensional Intensity Variation (비선형 평활화와 다차원의 명암변화에 기반을 둔 영상인식)

  • Cho, Yong-Hyun
    • Journal of the Korean Institute of Intelligent Systems
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    • v.24 no.5
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    • pp.504-511
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    • 2014
  • This paper presents a hybrid recognition method, which is based on the nonlinear histogram equalization and the multidimensional intensity variation of an images. The nonlinear histogram equalization based on a adaptively modified function is applied to improve the quality by adjusting the brightness of the image. The multidimensional intensity variation by considering the a extent of 4-step changes in brightness between the adjacent pixels is also applied to reflect accurately the attributes of image. The statistical correlation that is measured by the normalized cross-correlation(NCC) coefficient, is applied to comprehensively measure the similarity between the images. The NCC is considered by the intensity variation of each 2-direction(x-axis and y-axis) image. The proposed method has been applied to the problem for recognizing the 50-face images of 40*40 pixels. The experimental results show that the proposed method has a superior recognition performances to the method without performing the histogram equalization, or the linear histogram equalization, respectively.

Image Histogram Equalization Using Flexible Logistic Transformation Function (유연한 로지스틱 변환함수를 이용한 영상의 히스토그램 평활화)

  • Cho, Yong-Hyun
    • Journal of the Korean Institute of Intelligent Systems
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    • v.19 no.6
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    • pp.787-795
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    • 2009
  • This paper presents a histogram equalization based on the logistic function for enhancing the quality of images. The histogram equalization is a simple and effective spatial processing method that it enhances the quality by adjusting the brightness of image. The logistic function that is a nonlinear transformation function is applied to adaptively enhance the brightness of the image according to its intensity level frequency. We propose a flexible and asymmetrical logistic function by only using the intensity level with maximum frequency and the maximum intensity level in an histogram, and the total number of pixels. The proposed function excludes both the computation load of an exponential function and the heuristic setting of an optimal parameter values in the traditional logistic function. The proposed method has been applied for equalizing many images with a different resolution and histogram distribution. The experimental results show that the proposed method has the superior enhancement performances and the faster equalizing speed compared with the traditional histogram equalization and the adaptively modified histogram equalization, respectively. And the proposed histogram equalization can be used in various multimedia systems in real-time.

Studies on the multi-layered coated paper(I) - The effect of pre-coated layer formulation on top coated layer properties - (다층 도공지에 관한 연구(I) - 프리코팅층의 안료배합이 탑층의 물성에 미치는 영향 -)

  • Lee, Myoung-Seok;Kim, Sun-Kyung;Cho, Byoung-Uk;Lee, Yong-Kyu
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 2011.04a
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    • pp.251-263
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    • 2011
  • This study was carried out in order to investigate the effect of pre-coating layer on top-coating layer. The coated paper with five different formulations were prepared. The properties of coated paper were measured and correlation between pre and top-coated layer was evaluated. Paper gloss was increased with addition of clay and GCC that has smaller particle size. Roughness was decreased with using smaller particle GCC, clay and talc. The highest thickness was obtained with talc. Brightness and whiteness of pre-coated layer were affected to top-coated layer. GCC 60 shows the highest and ununiform water adsorption during 1sec. The adsorption was higher with increasing coated weight. Talc shows the excellent water adsorption properties due to its wettability. These results indicate that final printability and properties of top coating layer can be controlled with adjusting pre-coating layer.

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Analysis on Topographic Normalization Methods for 2019 Gangneung-East Sea Wildfire Area Using PlanetScope Imagery (2019 강릉-동해 산불 피해 지역에 대한 PlanetScope 영상을 이용한 지형 정규화 기법 분석)

  • Chung, Minkyung;Kim, Yongil
    • Korean Journal of Remote Sensing
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    • v.36 no.2_1
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    • pp.179-197
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    • 2020
  • Topographic normalization reduces the terrain effects on reflectance by adjusting the brightness values of the image pixels to be equal if the pixels cover the same land-cover. Topographic effects are induced by the imaging conditions and tend to be large in high mountainousregions. Therefore, image analysis on mountainous terrain such as estimation of wildfire damage assessment requires appropriate topographic normalization techniques to yield accurate image processing results. However, most of the previous studies focused on the evaluation of topographic normalization on satellite images with moderate-low spatial resolution. Thus, the alleviation of topographic effects on multi-temporal high-resolution images was not dealt enough. In this study, the evaluation of terrain normalization was performed for each band to select the optimal technical combinations for rapid and accurate wildfire damage assessment using PlanetScope images. PlanetScope has considerable potential in the disaster management field as it satisfies the rapid image acquisition by providing the 3 m resolution daily image with global coverage. For comparison of topographic normalization techniques, seven widely used methods were employed on both pre-fire and post-fire images. The analysis on bi-temporal images suggests the optimal combination of techniques which can be applied on images with different land-cover composition. Then, the vegetation index was calculated from the images after the topographic normalization with the proposed method. The wildfire damage detection results were obtained by thresholding the index and showed improvementsin detection accuracy for both object-based and pixel-based image analysis. In addition, the burn severity map was constructed to verify the effects oftopographic correction on a continuous distribution of brightness values.

Analysis of User Preferences in the Use of E-book Readers: Feature-Setting Options and Touchscreen Actions in a Smartphone Environment (스마트폰 환경에서 전자책 리더 기능 설정 옵션 및 터치스크린 동작 사용에 관한 사용자 선호도 분석)

  • Kim, Mihye
    • The Journal of the Korea Contents Association
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    • v.14 no.9
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    • pp.141-152
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    • 2014
  • The user interfaces of electronic-book (e-book) readers in the e-book market are highly diverse, and this has led to major usability issues. In this paper, we analyze user preferences in terms of feature-setting options and the use of touchscreen actions in the six most commonly used e-book readers for smartphnoes. We identify alternatives for these features, which can enhance the usability of e-book readers, based on these user preferences. The survey results for the feature-setting options show that it is desirable to support at least eight background colors, as well as the ability to specify the color of the background icons. Adjusting the screen brightness using a setting bar with the support of an auto-brightness option is desirable, as in using +/- buttons to adjust the font size, as well as approximately 10 font faces. We find that it is desirable to support fade, slide, scroll and curl page-turing options, in addition to a simple non-animated page-turning effect, and that page movement should be accomplished using a scroll bar with the support of the page movement features by entering a page number, and by using the table of contents as well as bookmarks. The survey results on the use of touchscreen options indicated that it is useful to be able to configure the screen layout of an e-book reader by dividing it into three areas: left, right, and center. And then, when users briefly touch the left and right areas, it is ideal to move to the previous and subsequent pages, respectively; and when they briefly touch the center region, it is desirable to display a touch feature menu. We believe that the results of this study may provide guidance in the design of user interfaces for e-book readers.

Development of the new meta-heuristic optimization algorithm inspired by a vision correction procedure: Vision Correction Algorithm (시력교정 과정에서 착안된 새로운 메타휴리스틱 최적화 알고리즘의 개발: Vision Correction Algorithm)

  • Lee, Eui Hoon;Yoo, Do Guen;Choi, Young Hwan;Kim, Joong Hoon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.3
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    • pp.117-126
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    • 2016
  • In this study, a new meta-heuristic optimization algorithm, Vision Correction Algorithm (VCA), designed according to the optical properties of glasses was developed. The VCA is a technique applying optometry and vision correction procedure to optimization algorithm through the process of myopic/hyperopic correction-brightness adjustment-compression enforcement-astigmatism adjustment. The proposed VCA unlike the conventional meta-heuristic algorithm is an automatically adjusting global/local search rate and global search direction based on accumulated optimization results. The proposed algorithm was applied to the representative optimization problem (mathematical and engineering problem) and results of the application are compared with that of the present algorithms.

AWM Driving Method with Hybrid Current Control for PM-OLED Panel (수동형 OLED를 위한 복합 전류 제어 기능을 갖는 AWM 구동방식)

  • Kim, Seok-Man;Lee, Je-Hoon;Hur, Yeo-Jin;Kim, Yong-Hwan;Cho, Kyoung-Rok
    • The Journal of the Korea Contents Association
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    • v.7 no.1
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    • pp.116-123
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    • 2007
  • This paper proposed a new amplitude width modulation for OLED data driver IC. The data driver controls brightness of OLED by adjusting amplitude and width of the data drive current pulse. There were two conventional methods; pulse amplitude modulation(PAM) and pulse width modulation(PWM). The PWM method suffered from lower light emitting time efficiency at low luminance signal. The PAM method suffered from large chip area using DACs for each column. The proposed method was aiming at accurately controlling of the current level by MSB data and light emitting efficiency by LSB data to improve the inefficiencies of the PAM and a PWM. The proposed AWM driver circuit implemented using $0.35-{\mu}m$ 3-poly 4-metal CMOS high voltage process. The simulation result shows the improvement in the accuracy of the gray level control even though the driver circuit is smaller than the PAM.

The Study of Development of Color-Mud for Boryeong Mud Festival by Color Pigment (착색안료를 이용한 보령머드축제용 유색머드의 개발)

  • Shim, Seung-Bo;Oh, Seong-Geun;Hong, Kyung-Hee;Chun, Yong-Jin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.6
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    • pp.2300-2305
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    • 2010
  • This study was performed about color-contained mud to provide fun and diversity for the event of mud self massage as a core program of Boryeong Mud Festival which has become one of representative festivals in Korea. Adjusting its own lower brightness of mud and based on the primary study performed about the expressivity of yellowish colors, inorganic colors (oxidized steel in red, ultra marine pink, ultra marine blue, chrome oxide green) were added for the development of colored mud in diverse colors on the basis of Korean traditional colors. It had been judged about each expressivity of color by methods of colormeter, naked eyes inspection and feeling of usage, etc. For the color decided, it had been examined about the coloring when it got wet with the cleaning condition so that it can be used for the event of mud self massage as a program of Boryeong Mud Festival to increase diversity of the Festival and also attempted to develope colored mud to show Korean traditional colors.

Backlight Compensation by Using a Novel Region of Interest Extraction Method (새로운 관심영역 추출 방법을 이용한 역광보정)

  • Seong, Joon Mo;Lee, Seong Shin;Lee, Songwook
    • KIPS Transactions on Software and Data Engineering
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    • v.6 no.6
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    • pp.321-328
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    • 2017
  • We have implemented a technique to correct the brightness, saturation, and contrast of an image according to the degree of light, and further compensate the backlight. Backlight compensation can be done automatically or manually. For manual backlight compensation, we have to select the region of interest (ROI). ROI can be selected by connecting the outline of the desired object. We make users select the region delicately with the new magnetic lasso tool. The previous lasso tool has a disadvantage that the start point and the end point must be connected. However, the proposed lasso tool has the advantage of selecting the region of interest without connecting the start point and the end point. We can automatically obtain various results of backlight compensation by adjusting the number of k-means clusters for texture extraction and the threshold value for binarization.