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Scattered Light Representation in Accordance with the Material Using Scatterer Template in Volume Rendering

볼륨 렌더링에서 산란자 템플릿을 이용한 재질별 산란광 표현

  • 이병준 (인하대학교 컴퓨터정보공학과) ;
  • 권구주 (인하대학교 컴퓨터정보공학과) ;
  • 신병석 (인하대학교 컴퓨터정보공학과)
  • Received : 2016.07.04
  • Accepted : 2016.08.24
  • Published : 2016.12.31

Abstract

For realistic rendering volume to calculate the light effects as well as the shade is essential. In order to produce the high quality of the resulting image, it is necessary to represent a global illumination, and it should be considered an indirect effect of the direct impact and scattering of light. It requires a lot of resources in order to perform this operation and, in particular, is very expensive when large amounts of data to be rendered as a volume data is consumed. In this paper, we generate a scatterer template according to the physical laws for each material. Considering that each object having material property stores photons of the template based on the Lambert illumination model. When the volume rendering in this paper, using the photon is stored in the template, based on the voxel to be sampled within the examination volume occluded, and it represents the global illumination of the scattering. Because the materials produced by the template requires a less resource only if comprised of a complex material, a simple operation can be expressed within the scattering volume at a low cost through.

사실적인 볼륨 렌더링을 위해서는 음영처리 뿐만 아니라 조명 효과를 계산하는 것이 필수적이다. 높은 품질의 결과영상을 만들어내기 위해서는 전역 조명을 표현할 필요가 있는데, 빛의 직접적인 영향과 산란에 따른 간접적인 영향을 고려해야 한다. 이러한 연산을 수행하기 위해서는 많은 자원이 필요하고, 특히 볼륨 데이터처럼 대용량의 데이터로 렌더링 할 때는 매우 많은 비용이 소모된다. 본 논문에서는 각 재질에 대해 물리적 법칙에 따른 산란자 템플릿을 생성한다. 각 물체들이 가지는 재질 특성을 고려하여 램버트 조명 모델을 기반으로 템플릿의 광자들을 저장한다. 본 논문에서 볼륨 렌더링을 할 때, 볼륨 내부에서 샘플링 되는 복셀을 기준으로 템플릿에 저장된 광자를 이용해 차폐를 검사하고, 산란에 따른 전역 조명을 표현한다. 재질별로 템플릿을 생성하기 때문에 매우 복잡한 물질들로 구성된 것만 아니라면 적은 자원을 필요로 하며, 간단한 연산을 통해 적은 비용으로 볼륨 내부의 산란을 표현할 수 있다.

Keywords

References

  1. Paul S. Calhoun et al., "Three-dimensional Volume Rendering of Spiral CT Data: Theory and Method 1," Radiographics, Vol.19, No.3, pp.745-764, 1999. https://doi.org/10.1148/radiographics.19.3.g99ma14745
  2. J. Kronander et al., "Efficient visibility encoding for dynamic illumination in direct volume rendering," IEEE Transactions on Visualization and Computer Graphics, Vol.18, No.3, pp.447-462, 2012. https://doi.org/10.1109/TVCG.2011.35
  3. M. Hadwiger et al., "GPU-accelerated deep shadow maps for direct volume rendering," SIGGRAPH/EUROGRAPHICS Conference on Graphics Hardware: Proceedings of the 21 st ACM SIGGRAPH/Eurographics Symposium on Graphics Hardware, Vienna, Austria, Vol.3, No.4, pp.49-52, 2006.
  4. M. Bunnell, "GPU gems, Dynamic ambient occlusion and indirect lighting," Addison-Wesley Professional, Aug., 2007.
  5. J. Kruger and R. Westermann, "Acceleration techniques for GPU-based volume rendering," Proceedings of the 14th IEEE Visualization 2003 (VIS'03), IEEE Computer Society, 2003.
  6. J. Diaz et al., "Real-time ambient occlusion and halos with summed area tables," Computers & Graphics, Vol.34, No.4, pp.337-350, 2010. https://doi.org/10.1016/j.cag.2010.03.005
  7. T. Ropinski et al., "Interactive volume rendering with dynamic ambient occlusion and color bleeding," Computer Graphics Forum, Vol.27, Iss.2, pp.567-576, 2008. https://doi.org/10.1111/j.1467-8659.2008.01154.x
  8. V. Solteszova et al., "A multidirectional occlusion shading model for direct volume rendering," Computer Graphics Forum, Vol.29, Iss.3, pp.883-891, 2010. https://doi.org/10.1111/j.1467-8659.2009.01695.x
  9. Yubo Zhang and Kwan-Liu Ma, "Fast global illumination for interactive volume visualization," Proceedings of the ACM SIGGRAPH Symposium on Interactive 3D Graphics and Games, ACM, 2013.
  10. J. Danskin, and P. Hanrahan, "Fast algorithms for volume ray tracing," Proceedings of the 1992 Workshop on Volume Visualization, ACM, 1992.
  11. P. Gautron, C. Delalandre, and J.-E. Marvie, "Extinction transmittance maps," SIGGRAPH Asia 2011 Sketches, ACM, 2011.
  12. W. Jarosz, M. Zwicker, and H. W. Jensen, "The beam radiance estimate for volumetric photon mapping," ACM SIGGRAPH 2008 Classes, ACM, 2008.
  13. H. W. Jensen and P. H. Christensen, "Efficient simulation of light transport in scenes with participating media using photon maps," Proceedings of the 25th Annual Conference on Computer Graphics and Interactive Techniques, ACM, 1998.
  14. D. Jonsson et al., "Historygrams: Enabling interactive global illumination in direct volume rendering using photon mapping," IEEE Transactions on Visualization and Computer Graphics, Vol.18, Iss.12, pp.2364-2371, 2012. https://doi.org/10.1109/TVCG.2012.232
  15. T. Whitted, "An improved illumination model for shaded display," ACM Siggraph 2005 Courses, ACM, 2005.
  16. P. Lacroute, and M. Levoy, "Fast volume rendering using a shear-warp factorization of the viewing transformation," Proceedings of the 21st Annual Conference on Computer Graphics and Interactive Techniques, ACM, 1994.
  17. Y. Sato, et al., "Three-dimensional multi-scale line filter for segmentation and visualization of curvilinear structures in medical images," Medical Image Analysis, Vol.2, No.2, pp.143-168, 1998. https://doi.org/10.1016/S1361-8415(98)80009-1
  18. R. Westermann, and B. Sevenich, "Accelerated volume ray-casting using texture mapping," Proceedings of the Conference on Visualization'01, IEEE Computer Society, 2001.
  19. Koo-Joo, Kwon and Byeong-Seok Shin, "Visualization of segmented color volume data using gpu," Advances in Artificial Reality and Tele-Existence, Springer Berlin Heidelberg, 1062-1069, 2006.