Multimodal Transfer Functions for Talbot-Lau Grating Interferometry Data

Talbot-Lau grating interferometry X-ray computed tomography (TLGI-XCT) generates three modalities depicting different features in the scanned specimen. The combination of two or even all three modalities is often required for an in-depth analysis of the material. We present a multimodal transfer function widget for this purpose. It enables users to edit the combined transfer functions of three modalities, resulting in a customized fused image. We implement methods to arrange the individual transfer functions in two different intuitive layouts. The weighting for each modality can be easily modified and the resulting fusion image is immediately updated. We provide a combined histogram over all modalities within a triangular visualization which we call trimodal heatmap. Through this interactive analysis technique, the user can quickly gain insights into the analysed material. We show the effectiveness of our technique with the help of real-world TLGI-XCT datasets.