Journal of the Institute of Electronics Engineers of Korea SP (대한전자공학회논문지SP)

The Institute of Electronics and Information Engineers (대한전자공학회)
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Ray Tracing Method Based on Spectral Distribution for Reproducing a Realistic Image

실사영상 재현을 위한 분광분포 기반의 광선추적기법

  • Lee Myong-Young (School of Electrical Engineering and Computer Science, Kyungpook National University) ;
  • Lee Cheol-Hee (Department of Computer Engineering, Andong Univ.) ;
  • Lee Ho-Keun (School of Electrical Engineering and Computer Science, Kyungpook National University) ;
  • Ha Yeong-Ho (School of Electrical Engineering and Computer Science, Kyungpook National University)
  • 이명영 (경북대학교 전자전기컴퓨터공학부) ;
  • 이철희 (안동대학교 컴퓨터공학과) ;
  • 이호근 (경북대학교 전자전기컴퓨터공학부) ;
  • 하영호 (경북대학교 전자전기컴퓨터공학부)
  • Published : 2004.01.01
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Abstract

In this paper, we propose an improved reproduction algorithm for a realistic image of the real scene based on the spectral distribution of lights and objects. The proposed method for the realistic image is focused on a more accurate reproduction of an image incident on the sight of the viewer. At first, to reproduce an image accurately incident on a sight of viewer, we used the backward ray tracing method based on spectral distribution of object and illuminant representing its physical characteristic used in real. Next, we propose utilizing the improved shading model of the reproduction algorithm of realistic image by applying Bouguer-Beer's law to consider an optical absorptive property of transparent objects. We also define a new ambient light term which is considered the diffuse reflection of neighboring objects instead of constant ambient light. The simulation results show that the proposed algorithm can reproduce the visually similar image with a scene incident on a sight of viewer.

본 논문에서는 관찰자의 시야에 들어오는 3차원 영상을 정확하게 재현하기 위한 분광분포 기반의 영상재현알고리즘을 제안한다. 빛의 투과 및 굴절을 모델링하기 위해 컴퓨터 그래픽에서 많이 사용되고 있는 광선추적기법을 이용하고, 정확한 실사영상(realistic image)을 재현하기 위하여 물체의 물리적 특성을 반영하는 분광분포를 고려하였다. 광원에서 출발한 빛을 추적하여 더욱 정확한 실사영상을 재현하기 위해 음영모델을 두 가지의 측면에서 개선하여 적용하였다. 첫째는, 빛이 투과할 때에 발생하는 에너지의 감소를 Bouguer-Beer의 법칙을 적용하여 고려하였다 둘째는, 일반적인 상수로 정의하던 주변광의 요소를 주위 물체들의 반사광을 고려한 새로운 주변광으로 개선하여 적용하였다. 제안한 기법을 이용한 시뮬레이션을 통하여 실사영상에 근접한 3차원 영상을 재현할 수 있었다.

Keywords

References

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