Title: Beyond Next-Token Alignment: Distilling Multimodal Large Language Models via Token Interactions
Primary area: applications to computer vision, audio, language, and other modalities
Keywords: MLLM, Token Alignment, Token Interaction

Abstract: Multimodal Large Language Models (MLLMs) have demonstrated impressive cross-modal understanding capabilities, yet their substantial model size poses significant challenges for widespread deployment. Knowledge distillation (KD) presents a promising solution for compressing these large-scale MLLMs. However, existing KD methods primarily rely on static next-token alignment, neglecting to model the dynamic token interactions, which embed essential capabilities for multimodal understanding and generation. To this end, we introduce **Align-TI**, a novel KD framework designed from the perspective of **T**oken **I**nteractions. Our approach is motivated by the insight that MLLMs rely on two primary interaction types: vision-instruction token interactions to extract instruction-relevant visual information, and intra-response token interactions for dynamic reasoning and coherent generation. Accordingly, Align-TI introduces two components: Instruction-aware Vision Alignment (IVA) and Transition Probability Alignment (TPA). IVA enables the student model to imitate the teacher's ability to extract instruction-relevant visual information by aligning on salient visual regions. TPA captures the teacher's dynamic generative logic by aligning the sequential token-to-token transition probabilities. Extensive experiments on standard multimodal benchmarks demonstrate the superiority of Align-TI. Notably, our approach achieves 3.7% relative improvement over direct supervised fine-tuning across multiple benchmarks. Moreover, our distilled Align-TI-2B even outperforms LLaVA-1.5-7B (a much larger MLLM) by 7.0%, establishing a new state-of-the-art distillation framework for training parameter-efficient MLLMs.

TL;DR: A novel MLLM knowledge distillation framework designed from the perspective of token interactions.