Closed-Form GPU-Accelerated Tensor Voting with Refinement

Helya Goharbavang, Omar Baig, Guoning Chen, David Mayerich

teaser
Structure tensor field labeling fiber orientation in an EM image of zebrafish tectum. Color indicates the eigenvector associated with \( |\lambda_0| \leq |\lambda_1| \). Saturation indicates eccentricity. (a) The raw EM image is used to produce a structure tensor field (b) using second-order finite differences. Methods to refine the field (all using \( \sigma=4 \)): (c) Gaussian blur, (d) original tensor voting, (e) tensor voting with refinement (\( p=6 \)), and (f) full implementation including the plate voting field. (h) The proposed method is shown overlayed on the original image, with insets showing a fiber bundle with each method shown as an overlay.

Abstract

Tensor fields can encode local image features for downstream algorithms. Common examples include the structure tensor and Hessian, which encode the local gradient and curvature. However, the results are sensitive to noise because they rely on finite difference methods. While this can be mitigated through low-pass filtering, this comes at the cost of resolution. Tensor voting (TV) provides a method of distributing tensor information across neighboring pixels based on Gestalt principles. However, these basic assumptions do not translate well to biomedical images, particularly surface and fiber extraction. In this paper, we add several features to the TV framework enabling more robust control of the refined field. Specifically, we reformulate TV to enable (1) tuning the vote field’s scope to reinforce highly directed structures, (2) normalized energy distribution so that TV can be applied iteratively or with other algorithms, (3) a closed-form solution for all terms and the corresponding plate tensor, and (4) a GPUbased algorithm for fast processing of large images.

Visualization

This is a demo of the 3D visualization toolkit for tensor fields. While the paper focuses on 2D tensor voting, this implementation extends to 3D and is available in the same repository. The toolkit enables interactive exploration of tensor fields, helping to analyze their structure and behavior.

teaser

Resources

Paper: Our paper is available on IEEE and locally.

Poster: Our poster is available here.

Code: Our code is available on Github.

Data: Our data (Serial EM) is available upon request.