DAP: Domain-aware Prompt Learning for Vision-and-Language Navigation
Ting Liu, Yue Hu, Wansen Wu, Youkai Wang, Kai Xu, Quanjun Yin
TL;DR
Vision-and-language navigation (VLN) suffers from a domain gap when applying web-trained pretrained models to in-domain VLN environments. The paper proposes Domain-aware Prompt Learning (DAP), a model-agnostic framework that injects in-domain knowledge via soft visual prompts into the visual encoder while keeping the backbone frozen. DAP leverages in-domain image-text pairs generated with CLIP, uses prompt tuning to ground object- and scene-level semantics, and demonstrates state-of-the-art performance on R2R and REVERIE. The results indicate that lightweight prompt-based adaptation can effectively bridge dataset domain gaps and enhance VLN performance with low training cost.
Abstract
Following language instructions to navigate in unseen environments is a challenging task for autonomous embodied agents. With strong representation capabilities, pretrained vision-and-language models are widely used in VLN. However, most of them are trained on web-crawled general-purpose datasets, which incurs a considerable domain gap when used for VLN tasks. To address the problem, we propose a novel and model-agnostic domain-aware prompt learning (DAP) framework. For equipping the pretrained models with specific object-level and scene-level cross-modal alignment in VLN tasks, DAP applies a low-cost prompt tuning paradigm to learn soft visual prompts for extracting in-domain image semantics. Specifically, we first generate a set of in-domain image-text pairs with the help of the CLIP model. Then we introduce soft visual prompts in the input space of the visual encoder in a pretrained model. DAP injects in-domain visual knowledge into the visual encoder of the pretrained model in an efficient way. Experimental results on both R2R and REVERIE show the superiority of DAP compared to existing state-of-the-art methods.
