Cross-Modal Few-Shot Learning with Second-Order Neural Ordinary Differential Equations
Yi Zhang, Chun-Wun Cheng, Junyi He, Zhihai He, Carola-Bibiane Schönlieb, Yuyan Chen, Angelica I Aviles-Rivero
TL;DR
SONO introduces a cross-modal few-shot learning framework that leverages Second-Order Neural ODEs to refine visual features while a text-initialized cross-modal classifier maintains efficient learning. A text-based augmentation strategy, Text-as-Image Augmentation, enriches training by exploiting CLIP's image-text alignment, and the classifier is initialized with text embeddings from class prompts to avoid repeated text-encoder passes. Empirical results across 11 datasets and domain-shift settings demonstrate state-of-the-art performance with strong robustness and competitive efficiency, including notable gains on challenging datasets like ImageNet-A. The work shows that higher-order dynamical systems can enhance feature expressiveness for vision-language tasks, offering a practical and scalable approach for few-shot and domain-generalized cross-modal learning.
Abstract
We introduce SONO, a novel method leveraging Second-Order Neural Ordinary Differential Equations (Second-Order NODEs) to enhance cross-modal few-shot learning. By employing a simple yet effective architecture consisting of a Second-Order NODEs model paired with a cross-modal classifier, SONO addresses the significant challenge of overfitting, which is common in few-shot scenarios due to limited training examples. Our second-order approach can approximate a broader class of functions, enhancing the model's expressive power and feature generalization capabilities. We initialize our cross-modal classifier with text embeddings derived from class-relevant prompts, streamlining training efficiency by avoiding the need for frequent text encoder processing. Additionally, we utilize text-based image augmentation, exploiting CLIP's robust image-text correlation to enrich training data significantly. Extensive experiments across multiple datasets demonstrate that SONO outperforms existing state-of-the-art methods in few-shot learning performance.
