RANSIC: Fast and Highly Robust Estimation for Rotation Search and Point Cloud Registration using Invariant Compatibility

TL;DR

RANSIC is a novel, fast, and robust method for rotation search and point cloud registration that effectively handles high outlier ratios by combining random sampling with invariant compatibility tests.

Contribution

It introduces a new paradigm that integrates random sampling with invariance-based compatibility tests, improving robustness and efficiency in outlier-heavy scenarios.

Findings

Handles over 95% outliers effectively

Recalls nearly 100% inliers in experiments

Outperforms state-of-the-art methods in speed and robustness

Abstract

Correspondence-based rotation search and point cloud registration are two fundamental problems in robotics and computer vision. However, the presence of outliers, sometimes even occupying the great majority of the putative correspondences, can make many existing algorithms either fail or have very high computational cost. In this paper, we present RANSIC (RANdom Sampling with Invariant Compatibility), a fast and highly robust method applicable to both problems based on a new paradigm combining random sampling with invariance and compatibility. Generally, RANSIC starts with randomly selecting small subsets from the correspondence set, then seeks potential inliers as graph vertices from the random subsets through the compatibility tests of invariants established in each problem, and eventually returns the eligible inliers when there exists at least one K-degree vertex (K is automatically updated depending on the problem) and the residual errors satisfy a certain termination condition at the same time. In multiple synthetic and real experiments, we demonstrate that RANSIC is fast for use, robust against over 95% outliers, and also able to recall approximately 100% inliers, outperforming other state-of-the-art solvers for both the rotation search and the point cloud registration problems.