Modeling of Lizard Skin Pattern by Cellular Automaton

Abstract

Properties of lizard skin pattern (LSP) comprised of light and dark scales are characterized statistically and compared with the corresponding properties of a random binary field (RBF). The similarity function of these fields exhibits an outstanding peak that indicates their stochastic character. Stochastic properties are still more generally indicated by the probability distribution of scales in hexagonal cells comprised of a center and ring. It shows that similar scales are grouped together in LSP, but not in RBF. This difference is characterized by the conditional probability that reveals why LSP appears more striped than RBF. For generation of fields resembling LSP the cellular automaton (CA) is adapted to LSP by the non-parametric regression. Its deterministic performance is demonstrated by the operation on RBF. By adding a random number generator to this model the deterministic CA is generalized to a probabilistic one. Its actions cause more expressive changing of the input field as the actions of the deterministic CA.