arXiv Computer Vision
Sep 28

ProCAP: Probabilistic Cross-Attentive Prompt Learning for Vision-Language Models

ProCAP introduces a probabilistic cross-attentive prompt learning framework for vision-language models like CLIP, enabling improved cross-modal interaction without updating the backbone. It jointly learns visual and textual prompt tokens, linking them via stacked bidirectional multi-head cross-attention to refine each branch across prompt depth. The method incorporates Gaussian parameterization of prompt tokens, lightweight KL and L2 regularization, and a compact symmetric InfoNCE head to align image features with class-level text representations, achieving strong few-shot base-to-novel performance and competitive transfer results across multiple datasets and benchmarks.

By Hiwa Azeez Abbas, Fatemeh Daneshfar, Moloud Abdar
arXiv Computer Vision
Oct 19

FedRAPP: Federated Test-Time Prompt Tuning for Vision-Language Models with Reliability-Aware Prompt Personalization

FedRAPP introduces a personalized aggregation framework for federated test‑time prompt tuning of vision‑language models, enabling distributed clients to adapt soft prompts on unlabeled test streams without source data. The method incorporates reliability‑aware client assessment, server‑side exponential moving‑average prompt memory, and similarity‑guided peer aggregation to selectively combine information from reliable and compatible clients. Experiments on nine CLIP benchmark datasets and ImageNet variants show that FedRAPP consistently outperforms standard federated aggregation baselines under heterogeneous client distributions while preserving prompt‑only adaptation efficiency.

By Syed Md. Ahnaf Hasan, Md Akil Raihan Iftee, Sajib Mistry, Amin Ahsan Ali, AKM Mahbubur Rahman
arXiv Machine Learning
Sep 22

Tackling Feature-Classifier Mismatch in Federated Learning via Prompt-Driven Feature Transformation

The paper introduces FedPFT, a federated learning framework that tackles the feature‑classifier mismatch problem by using personalized prompts processed through a shared self‑attention transformation module. Unlike prior methods that either degrade the feature extractor or address the mismatch only after training, FedPFT aligns local features with the global classifier during training, improving aggregation and model performance. Experiments demonstrate that FedPFT surpasses state‑of‑the‑art methods by up to 5.07%, and gains up to 7.08% when combined with collaborative contrastive learning.

By Xinghao Wu, Xuefeng Liu, Jianwei Niu, Guogang Zhu, Mingjia Shi, Shaojie Tang, Jing Yuan
arXiv Computer Vision
Oct 2

Beyond Domain-Level Adaptation: Margin-Oriented Semantic-Appearance Interaction Correction for Personalized Federated Vision-Language Models

The paper introduces MOSAIC, a method for personalized federated vision‑language models that addresses domain heterogeneity by focusing on class‑specific cross‑domain residuals. It constructs a decision‑aware harmfulness score to identify residuals that hurt image‑text decision margins, then uses a low‑rank residual adapter with shared class factors and private domain factors, an image‑conditioned gate, and harmful‑pair‑aware reweighting to refine local updates. Experiments on Office31, OfficeHome, and DomainNet100 show consistent improvements in macro‑client top‑1 accuracy across various domain‑shift scenarios.

By Wentao Yue, Qingyu Mao, Tianyou Lai, Ahmed M. Abdelmoniem, Qilei Li