Abstract
Images have characteristic statistics that can be characterized in terms of the responses of wavelet or Gabor-like filters. There has been a great deal of interest in the fact that images have sparse (kurtotic) statistics in the wavelet domain, with implications for efficient image encoding in biological and artificial systems. If we set aside the issue of efficiency, we are still left with the problem of seeing. We have been studying the ways in which filter statistics can reveal useful information about surfaces, including albedo, shading, and gloss. We find that odd order statistics such as skewness are quite useful in extracting information about reflectance and gloss, and we also find evidence that humans make use of this information. It is straightforward to compute skewness with physiological mechanisms.