Contextual AD Narration with Interleaved Multimodal Sequence
Hanlin Wang, Zhan Tong, Kecheng Zheng, Yujun Shen, Limin Wang
TL;DR
This work addresses automatic Audio Description generation for long-form video by introducing Uni-AD, which prompts frozen LLMs with interleaved multimodal sequences that fuse video frames, character exemplars, text, and context. It couples a visual mapping network to align multi-modal content, a character-refinement module to isolate AD-relevant characters, and contextual information plus a contrastive loss to improve coherence and diversity. Empirical results on MAD-eval-Named, CMDAD, and TVAD show state-of-the-art performance and robustness across settings, with improvements from stronger visual encoders and larger LLMs. The approach is scalable and accompanies public code to facilitate reproducibility and broader adoption in AD generation research.
Abstract
The Audio Description (AD) task aims to generate descriptions of visual elements for visually impaired individuals to help them access long-form video content, like movies. With video feature, text, character bank and context information as inputs, the generated ADs are able to correspond to the characters by name and provide reasonable, contextual descriptions to help audience understand the storyline of movie. To achieve this goal, we propose to leverage pre-trained foundation models through a simple and unified framework to generate ADs with interleaved multimodal sequence as input, termed as Uni-AD. To enhance the alignment of features across various modalities with finer granularity, we introduce a simple and lightweight module that maps video features into the textual feature space. Moreover, we also propose a character-refinement module to provide more precise information by identifying the main characters who play more significant roles in the video context. With these unique designs, we further incorporate contextual information and a contrastive loss into our architecture to generate smoother and more contextually appropriate ADs. Experiments on multiple AD datasets show that Uni-AD performs well on AD generation, which demonstrates the effectiveness of our approach. Our code is available at: https://github.com/ant-research/UniAD.
