Mitigating Hallucination in Large Vision-Language Models via Adaptive Attention Calibration
Journal:
arXiv
Published Date:
May 27, 2025
Abstract
Large vision-language models (LVLMs) achieve impressive performance on
multimodal tasks but often suffer from hallucination, and confidently describe
objects or attributes not present in the image. Current inference-time
interventions, while training-free, struggle to maintain accuracy in open-ended
and long-form generation scenarios. We introduce the Confidence-Aware Attention
Calibration (CAAC) framework to address this challenge by targeting two key
biases: spatial perception bias, which distributes attention disproportionately
across image tokens, and modality bias, which shifts focus from visual to
textual inputs over time. CAAC employs a two-step approach: Visual-Token
Calibration (VTC) to balance attention across visual tokens, and Adaptive
Attention Re-Scaling (AAR) to reinforce visual grounding based on the model's
confidence. This confidence-driven adjustment ensures consistent visual
alignment during generation. Experiments on CHAIR, AMBER, and POPE benchmarks
demonstrate that CAAC outperforms baselines, particularly in long-form
generations, effectively reducing hallucination.