Geometry-Anchored Transport Framework for Exemplar-Free Class-Incremental Learning
For researchers in class-incremental learning, this work addresses the problem of anisotropic representation drift in exemplar-free settings, offering a method that avoids decoupled fine-tuning.
The paper tackles exemplar-free class-incremental learning, proposing a Geometry-Anchored Transport Framework that integrates feature transport as an endogenous training constraint. It achieves consistent improvements over post-hoc alternatives on CIFAR-100, TinyImageNet, and ImageNet-100.
Exemplar-free class-incremental learning (EFCIL) requires stable decision boundaries within a shifting feature space. While maintaining class-conditional Gaussian statistics provides a principled classification strategy, these parametric summaries remain sensitive to anisotropic representation drift. Existing methods often transport these statistics across tasks using a decoupled, post-hoc paradigm: optimizing a backbone without explicit geometric constraints can distort the legacy manifold, limiting the precision of retroactive alignment. In this paper, we formulate feature transport as an endogenous training constraint rather than a separate post-task step, presenting the Geometry-Anchored Transport Framework. First, we derive an Analytic Geometric Anchor via Mahalanobis-aligned regression to mitigate macroscopic anisotropic drift. Second, we introduce a Topology-Aware Evolution objective that regularizes localized manifold degradation while calibrating a residual network against the analytic prior. By coupling manifold evolution with transport constraints during the primary training phase, our framework mitigates evaluation errors without requiring decoupled fine-tuning. Experiments across CIFAR-100, TinyImageNet, and ImageNet-100 demonstrate that the proposed framework consistently improves upon existing post-hoc alternatives under strict exemplar-free constraints.