Power Variable Projection for Initialization-Free Large-Scale Bundle Adjustment
- URL: http://arxiv.org/abs/2405.05079v5
- Date: Tue, 13 Aug 2024 13:25:34 GMT
- Title: Power Variable Projection for Initialization-Free Large-Scale Bundle Adjustment
- Abstract summary: We introduce Power Variable Projection (PoVar) to solve small-scale Bundle Adjustment problems.
We experimentally demonstrate that our solver achieves state-of-the-art results in terms of speed and accuracy.
- Score: 39.997922776362174
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: Most Bundle Adjustment (BA) solvers like the Levenberg-Marquardt algorithm require a good initialization. Instead, initialization-free BA remains a largely uncharted territory. The under-explored Variable Projection algorithm (VarPro) exhibits a wide convergence basin even without initialization. Coupled with object space error formulation, recent works have shown its ability to solve small-scale initialization-free bundle adjustment problem. To make such initialization-free BA approaches scalable, we introduce Power Variable Projection (PoVar), extending a recent inverse expansion method based on power series. Importantly, we link the power series expansion to Riemannian manifold optimization. This projective framework is crucial to solve large-scale bundle adjustment problems without initialization. Using the real-world BAL dataset, we experimentally demonstrate that our solver achieves state-of-the-art results in terms of speed and accuracy. To our knowledge, this work is the first to address the scalability of BA without initialization opening new venues for initialization-free structure-from-motion.
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