A Median Cut Algorithm for Light Probe Sampling
A Median Cut Algorithm for Light Probe Sampling
SIGGRAPH 2005 Poster
Paul Debevec
USC Institute for Creative Technologies

Published in: Reinhard, Ward, Pattanaik, and Debevec, High Dynamic Range Imaging: Acquistion, Display, and Image-Based Lighting,
Ch. 9, "Image-Based Lighting", Morgan-Kaufmann, 2005, pp. 430-433.



We present a technique for approximating a light probe image as a constellation of light sources based on a median cut algorithm. The algorithm is simple to implement, runs efficiently, and can realistically represent a complex lighting environment with as few as 64 point light sources.


SIGGRAPH 2005 Poster Abstract:

Supplemental Images Poster Abstract:

  • There is an implementation of the Median Cut sampling algorithm as an HDR Shop 1.0 plugin in Francesco Banterle's Banty's Toolkit beta 1.1, which produces a simple text file with the light parameters.

  • The algorithm is also implemented in Jeremy Pronk's Image-Based Lighting Tools package, with support for Maya and Mental Ray.