• Title/Summary/Keyword: 초점화

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Foreground Extraction and Depth Map Creation Method based on Analyzing Focus/Defocus for 2D/3D Video Conversion (2D/3D 동영상 변환을 위한 초점/비초점 분석 기반의 전경 영역 추출과 깊이 정보 생성 기법)

  • Han, Hyun-Ho;Chung, Gye-Dong;Park, Young-Soo;Lee, Sang-Hun
    • Journal of Digital Convergence
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    • v.11 no.1
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    • pp.243-248
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    • 2013
  • In this paper, depth of foreground is analysed by focus and color analysis grouping for 2D/3D video conversion and depth of foreground progressing method is preposed by using focus and motion information. Candidate foreground image is generated by estimated movement of image focus information for extracting foreground from 2D video. Area of foreground is extracted by filling progress using color analysis on hole area of inner object existing candidate foreground image. Depth information is generated by analysing value of focus existing on actual frame for allocating depth at generated foreground area. Depth information is allocated by weighting motion information. Results of previous proposed algorithm is compared with proposed method from this paper for evaluating the quality of generated depth information.

Effects of Wearing Corrective Glasses for Presbyopia on Age-related Hyperopic Shifts and Reading Addition (노안보정용 안경 착용이 연령관련 원시화와 근용가입도 변화에 미치는 영향)

  • Lee, Koon-Ja;Kim, Jin-Han;Mun, Mi-Young;Leem, Hyun-Sung
    • Journal of Korean Ophthalmic Optics Society
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    • v.14 no.3
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    • pp.65-73
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    • 2009
  • Purpose: This study was conducted to investigate the changes in distance refractive power and reading addition that occur after wearing corrective glasses for prebyopia. Methods: The subjects aged 42 to 75 years who had no ophthalmologic diseases and did not undergo cataract or retina surgery, had a corrected visual acuity of 20/20 and did not have a previous history of wearing corrective glasses for presbyopia. These subjects were divided into 3 groups: the control, reading spectacles and multifocals wearing group and they were measured for distance refractive power and reading addition at their visit. The maximum follow-up period was 73 months. Results: As for distance refractive power, the power tends to shift to hyperopia depending on age (r=0.486, p<.001) and 50.0% of the subjects increased plus power during this study period. Plus power Increments per year in distance refractive power in the reading spectacle wearing group were significantly different with control and multifocals wearing group (p<.05). On the other hand, the multifocals wearing group's increments were not different with control. Increments in reading addition were also increased in the reading spectacles group than in the control and multifocals wearing groups (p<.05). Conclusions: The age related hyperopic shift could be occurred in the elderly people, routine refraction is mandatory. And reading spectacles could induce an age related hyperopic shift and the additional need for reading addition that the prescription of multifocals may reduce changes in distance refractive power and reading addition.

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Quantitative analysis of increase in depth of focus using Wigner distribution function (Wigner 분포 함수를 초점 심도 증가의 정량적 해석)

  • 장남영;강호정;은재정;최평석
    • Korean Journal of Optics and Photonics
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    • v.11 no.6
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    • pp.385-389
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    • 2000
  • A phase-retardation function which was derived from Wigner distribution function (WDF) is used to increase a focal depth of a radially symmetric optical system. The WDF for one-dimensional signal is represented as a two-dimensional function of phasespace ($\chi,\zeta$), and a normalized irradiance is described as a form of the Strehl ratio (SR). The increase in the focal depth is accomplished by delivering a shearing tilt a that represents a characteristic of free space propagation with simple manipulation in the WDF space. In this paper we propose a method for evaluating the focal depth quantitatively by representing the phaseretardation function in terms of the focal depth term. In order to verify the validity of the proposed method, we compared the numerically analyzed result with that of J. Sochki's study. study.

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Autofocusing Mechanism of a Triple-Magnification Infrared System (3중 배율 적외선 영상 장비의 자동 초점 조절 방안)

  • Jung, Hyojung;Jeong, Suseong;Yang, Yunseok;Lee, Yongchun;Han, Jeongsu
    • Korean Journal of Optics and Photonics
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    • v.31 no.6
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    • pp.314-320
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    • 2020
  • The optics used in an infrared imaging system has a strong refractive-index change according to temperature, so an autofocus control function is essential for a military infrared imaging system with a wide operating-temperature range. In this study, we design a triple-magnification infrared imaging system, and to compensate for the change in refractive index according to temperature we measure the change in the lens focus according to temperature. The autofocus control function was implemented by using the measured movement amount, and we could obtain an image with satisfactory resolution performance over a wide range of operating temperatures.

Adaptive Binarization for Camera Image by Image Quality Estimation (카메라 영상의 화질 분석에 의한 적응적 이진화)

  • Kim, In-Jung
    • Proceedings of the Korea Information Processing Society Conference
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    • 2006.11a
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    • pp.65-68
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    • 2006
  • 카메라로 촬영한 문서 영상의 분석 및 인식을 위한 적응적 이진화 방법을 제안한다. 먼저 카메라 영상의 화질을 분석하여 정량화하는 방법을 제안한다. 그 후 다양한 화질의 카메라 영상에 대하여 제안한 방법으로 측정한 화질과 그 화질에 적합한 이진화 파라미터간의 상관 관계를 통계적으로 분석한다. 그 후 그들간의 상관 관계를 이용하여 입력 영상의 화질에 적합한 이진화 파라미터를 자동으로 추정하도록 함으로써 화질 변화에 대한 적응력을 강화하였다. 실험을 통해 초점 및 잡영의 상태에 따라 적절한 파라미터를 추정함으로써 화질 변화에 적응하는 결과를 확인하였다.

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Analysis on the Validity of 'Point of Knowing' in Elementary Mathematics Textbook (초등학교 수학 교과서에 나타나는 앎의 시점의 타당성 분석)

  • Kang, Taeseok;Kang, Wan;Lim, Dawon
    • Journal of Educational Research in Mathematics
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    • v.26 no.4
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    • pp.731-754
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    • 2016
  • The purpose of the study is to identify the point of knowing. The point of knowing is the time, which indicates that 'knowing' occurs in the recognition process. To understand recognition process, the researchers analyzed the questions in units of lessons presented in elementary mathematics textbooks. The researchers analyzed the validity of the point of knowing and found out the basis of the point of knowing. The results are as follows. First, the point of knowing is time to expect to change from a leaner's 'not-knowing' to 'knowing'. Second, the point of knowing can be identified with the questions on textbooks to ask students to do practical action. Third, the point of knowing is closely related to instructional objective in a class. Fourth, in relation to subsidiary awareness and focal awareness, the point of knowing corresponds to focal awareness. Fifth, the point of knowing is equivalent to the inflection point at which personalization/contextualization is changed into depersonalization/decontextualization.