ALTA  alpha

Data formats

ALTA can open common BRDF data formats such as:

We also provide our text-based data format (cf. format) that is compatible with Gnuplot.

Vertical Segment interpolation with Rational Functions

ALTA can perform rational interpolation in the sense of Pacanowski et al. [2012]. Multiple implementations are provided with various library for the quadratic solver:

We also provide plugin to perform least-square interpolation of rational functions. These plugins are based on Eigen's solvers. Due to the ill-posed formulation of the least-square method, the solution provided by those plugins might have singularities (denominator equals to zero) in the definition domain.

Non-linear fitting

ALTA can perform non-linear optimisation to fit parametric BRDF models to data. It supports a wide variety of non-linear optimizers such as:

Analytic BRDF models

We try to provide as much parametric BRDF models as possible. You will find the list of currently supported BRDF models in the Function plugins list page.

Scripting mechanisms

Writing command lines can be burdensome. To avoid having to write lengthy command lines, we provide a scripting mechanism to launch ALTA commands from XML formatted files or Python bindings.