Nonlinear phase portrait models for oriented textures

Nonlinear differential equations in Taylor series form are employed to model oriented textures. These models build upon the linear phase portrait description. Inclusion of higher order nonlinear terms provides a more accurate description in critical point regions. Nonlinear models containing multiple critical points are generated from linear phase portrait descriptions. The resulting models are highly compact descriptors, in that the flow-like textures of complex patterns are described by a single nonlinear system of differential equations