  Directional dark-field imaging is an emerging x-ray modality that is
sensitive to unresolved anisotropic scattering from sub-pixel sample
microstructures. A single-grid imaging set-up can be used to capture dark-field
images by looking at changes in a grid pattern projected upon the sample. By
creating analytical models for the experiment, we have developed a single-grid
directional dark field retrieval algorithm that can extract dark-field
parameters such as the dominant scattering direction, and the semi-major and
-minor scattering angles. We show that this method is effective even in the
presence of high image noise, allowing for low dose and time sequence imaging.
