Distilling Implicit Multimodal Knowledge into Large Language Models for Zero-Resource Dialogue Generation
Bo Zhang, Hui Ma, Jian Ding, Jian Wang, Bo Xu, Hongfei Lin
TL;DR
This work tackles zero-resource dialogue generation by leveraging implicit visual knowledge distilled from large image-text corpora. It introduces VIKDF, a two-stage framework that first distills visual cues with an Implicit Query Transformer (IQ-Former) and then fuses them into a frozen LLM via Bidirectional Variational Information Fusion (BVIF). The approach demonstrates state-of-the-art performance on zero-resource benchmarks (Image-Chat and Reddit Conversation), supported by comprehensive automatic and human evaluations, ablations, and case studies. The results highlight the value of implicit multimodal signals for enriching dialogue generation when explicit multimodal data is unavailable, with evidence of robustness across different LLM backbones and strong generalization. Overall, VIKDF advances multimodal dialogue research by showing how implicit knowledge can be effectively learned and integrated to produce coherent, relevant, and informative conversations in resource-constrained settings.
Abstract
Integrating multimodal knowledge into large language models (LLMs) represents a significant advancement in dialogue generation capabilities. However, the effective incorporation of such knowledge in zero-resource scenarios remains a substantial challenge due to the scarcity of diverse, high-quality dialogue datasets. To address this, we propose the Visual Implicit Knowledge Distillation Framework (VIKDF), an innovative approach aimed at enhancing LLMs for enriched dialogue generation in zero-resource contexts by leveraging implicit multimodal knowledge. VIKDF comprises two main stages: knowledge distillation, using an Implicit Query Transformer to extract and encode visual implicit knowledge from image-text pairs into knowledge vectors; and knowledge integration, employing a novel Bidirectional Variational Information Fusion technique to seamlessly integrate these distilled vectors into LLMs. This enables the LLMs to generate dialogues that are not only coherent and engaging but also exhibit a deep understanding of the context through implicit multimodal cues, effectively overcoming the limitations of zero-resource scenarios. Our extensive experimentation across two dialogue datasets shows that VIKDF outperforms existing state-of-the-art models in generating high-quality dialogues. The code is available at https://github.com/zhangbo-nlp/VIKDF.
