Illumination direction from texture shading.

@article{Koenderink2003IlluminationDF,
  title={Illumination direction from texture shading.},
  author={Jan J. Koenderink and Andrea J. van Doorn and Astrid M. L. Kappers and Susan F. te Pas and Sylvia C. Pont},
  journal={Journal of the Optical Society of America. A, Optics, image science, and vision},
  year={2003},
  volume={20 6},
  pages={987-95}
}
We investigate the ability of human observers to judge the direction of illumination from image texture. Photographs of 61 real surfaces were used, taken from the Columbia-Utrecht Reflectance and Texture (Curet) database (http:/www.cs.columbia.edu/CAVE/curet). All samples were normally viewed but obliquely illuminated, the elevation of the source being 22.5 degrees, 45.0 degrees, or 67.5 degrees. The illumination was with a collimated, parallel beam. Stimuli were presented in random orientation… CONTINUE READING