L. Schjøth, J. R. Frisvad, K. Erleben, Jon Sporring


The finite frame rate also used in computer animated films is cause of adverse temporal aliasing effects. Most noticeable of these is a stroboscopic effect that is seen as intermittent movement of fast moving illumination. This effect can be mitigated using non-zero shutter times, effectively, constituting a temporal smoothing of rapidly changing illumination. In global illumination temporal smoothing can be achieved with distribution ray tracing (Cook et al., 1984). Unfortunately, this, and resembling methods, requires a high temporal resolution as samples has to be drawn from in-between frames. We present a novel method which is able to produce high quality temporal smoothing for indirect illumination without using in-between frames. Our method is based on ray differentials (Igehy, 1999) as it has been extended in (Sporring et al., 2009). Light rays are traced as bundles creating footprints, which are used to reconstruct indirect illumination. These footprints expand into the temporal domain such that light rays interacting with non-static scene elements draw a path reacting to the elements movement.


  1. Cammarano, M. and Jensen, H. W. (2002). Time dependent photon mapping. In EGRW 7802: Proceedings of the 13th Eurographics workshop on Rendering, pages 135-144, Aire-la-Ville, Switzerland, Switzerland. Eurographics Association.
  2. Christensen, P. H., Laur, D. M., Fong, J., Wooten, W. L., and Batali, D. (2003). Ray differentials and multiresolution geometry caching for distribution ray tracing in complex scenes. In Proceedings of Eurographics 2003, Computer Graphics Forum, pages 543-552. Blackwell Publishing Inc.
  3. Cook, R. L., Porter, T., and Carpenter, L. (1984). Distributed ray tracing. SIGGRAPH Comput. Graphics, 18(3):137-145.
  4. Durand, F., Holzschuch, N., Soler, C., Chan, E., and Sillion, F. X. (2005). A frequency analysis of light transport. In Marks, J., editor, ACM SIGGRAPH 2005, pages 1115-1126.
  5. Egan, K., Tseng, Y.-T., Holzschuch, N., Durand, F., and Ramamoorthi, R. (2009). Frequency Analysis and Sheared Reconstruction for Rendering Motion Blur. SIGGRAPH (ACM Transactions on Graphics), 28(3):93:1-93:13.
  6. Gjøl, M., Larsen, B. D., and Christensen, N.-J. (2008). Final gathering using ray differentials. In Proceedings of WSCG 2008, pages 41-46.
  7. Haeberli, P. and Akeley, K. (1990). The accumulation buffer: hardware support for high-quality rendering. In SIGGRAPH 7890: Proceedings of the 17th annual conference on Computer graphics and interactive techniques, pages 309-318, New York, NY, USA. ACM.
  8. Igehy, H. (1999). Tracing ray differential. In Rockwood, A., editor, Siggraph 1999, Computer Graphics Proceedings, pages 179-186, Los Angeles. Addison Wesley Longman.
  9. Myszkowski, K., Tawara, T., Akamine, H., and Seidel, H.- P. (2001). Perception-guided global illumination solution for animation rendering. In SIGGRAPH 7801: Proceedings of the 28th annual conference on Computer graphics and interactive techniques, pages 221-230, New York, NY, USA. ACM.
  10. Schjøth, L., Frisvad, J. R., Erleben, K., and Sporring, J. (2007). Photon differentials. In GRAPHITE 7807: Proceedings of the 5th international conference on Computer graphics and interactive techniques in Australia and Southeast Asia, pages 179-186, New York, NY, USA. ACM.
  11. Sporring, J., Schjøth, L., and Erleben, K. (2009). Spatial and Temporal Ray Differentials. Technical Report 09/04, Institute of Computer Science, University of Copenhagen, Copenhagen, Denmark. ISSN: 0107- 8283.
  12. Tawara, T., Myszkowski, K., Dmitriev, K., Havran, V., Damez, C., and Seidel, H.-P. (2004). Exploiting temporal coherence in global illumination. In SCCG 7804:

Paper Citation

in Harvard Style

Schjøth L., R. Frisvad J., Erleben K. and Sporring J. (2010). TEMPORAL PHOTON DIFFERENTIALS . In Proceedings of the International Conference on Computer Graphics Theory and Applications - Volume 1: GRAPP, (VISIGRAPP 2010) ISBN 978-989-674-026-9, pages 54-61. DOI: 10.5220/0002847800540061

in Bibtex Style

author={L. Schjøth and J. R. Frisvad and K. Erleben and Jon Sporring},
booktitle={Proceedings of the International Conference on Computer Graphics Theory and Applications - Volume 1: GRAPP, (VISIGRAPP 2010)},

in EndNote Style

JO - Proceedings of the International Conference on Computer Graphics Theory and Applications - Volume 1: GRAPP, (VISIGRAPP 2010)
SN - 978-989-674-026-9
AU - Schjøth L.
AU - R. Frisvad J.
AU - Erleben K.
AU - Sporring J.
PY - 2010
SP - 54
EP - 61
DO - 10.5220/0002847800540061