Mitigating Object Hallucinations in Large Vision-Language Models via Attention Calibration
Journal:
arXiv
Published Date:
Feb 4, 2025
Abstract
Large Vision-Language Models (LVLMs) exhibit impressive multimodal reasoning
capabilities but remain highly susceptible to object hallucination, where
models generate responses that are not factually aligned with the visual
content. Recent works attribute this issue to an inherent bias of LVLMs where
vision token attention map has a fixed correlation with spatial position, and
propose to mitigate this issue by reordering visual tokens. However, we find
that different LVLMs exhibit different correlations between attention and
spatial position, which makes the existing solution difficult to generalize to
other LVLMs. To address this issue, we first introduce a training-free
solution, Uniform Attention Calibration (UAC), that estimates the bias from
single meaningless input image and applies a calibration matrix to rectify
attention imbalances. To further alleviate the bias, we relax the assumption of
single meaningless input in UAC and introduce a fine-tuning solution, Dynamic
Attention Calibration (DAC), that enforces the consistent outputs wherever the
object locates in the image via a plug-and-plays module. Comprehensive
experiments across multiple benchmarks demonstrate that UAC and DAC
significantly reduce object hallucination while improving general multimodal
alignment. Our methods achieve state-of-the-art performance across diverse LVLM
architectures on various metrics.