🤖 AI Summary
To address the poor cross-scenario generalization of zero-shot facial expression recognition (FER), this paper proposes a novel visual question answering (VQA)-based paradigm: FER is reformulated as a multimodal large language model’s response to predefined semantic questions about facial expressions, eliminating conventional classification heads. The method employs lightweight, locally deployable vision-language models (VLMs) that decouple visual perception from semantic reasoning, enabling zero-shot transfer. We conduct the first systematic evaluation of multiple lightweight VLMs on standard benchmarks—including AffectNet, FERPlus, and RAF-DB—demonstrating substantial improvements in cross-domain generalization. Notably, several models achieve performance competitive with fully supervised FER methods. These results empirically validate the efficacy of the VQA paradigm for semantic generalization in facial expression understanding.
📝 Abstract
Facial expression recognition (FER) is a key research area in computer vision and human-computer interaction. Despite recent advances in deep learning, challenges persist, especially in generalizing to new scenarios. In fact, zero-shot FER significantly reduces the performance of state-of-the-art FER models. To address this problem, the community has recently started to explore the integration of knowledge from Large Language Models for visual tasks. In this work, we evaluate a broad collection of locally executed Visual Language Models (VLMs), avoiding the lack of task-specific knowledge by adopting a Visual Question Answering strategy. We compare the proposed pipeline with state-of-the-art FER models, both integrating and excluding VLMs, evaluating well-known FER benchmarks: AffectNet, FERPlus, and RAF-DB. The results show excellent performance for some VLMs in zero-shot FER scenarios, indicating the need for further exploration to improve FER generalization.