Statistics of natural images: Scaling in the woods

This work gathers images from the woods and finds that these scenes possess an ensemble scale invariance, and this non-Gaussian character cannot be removed through local linear filtering, meaning information is maximized at fixed channel variance.

Abstract

We study the statistics of an ensemble of images taken in the woods. Distributions of local quantities such as contrast are scale invariant and have nearly exponential tails. Power spectra exhibit scaling with a nontrivial exponent. These data limit the information content of natural images and point to the importance of gain-control strategies in visual processing.