English

TOD3Cap: Towards 3D Dense Captioning in Outdoor Scenes

Computer Vision and Pattern Recognition 2024-06-07 v2

Abstract

3D dense captioning stands as a cornerstone in achieving a comprehensive understanding of 3D scenes through natural language. It has recently witnessed remarkable achievements, particularly in indoor settings. However, the exploration of 3D dense captioning in outdoor scenes is hindered by two major challenges: 1) the domain gap between indoor and outdoor scenes, such as dynamics and sparse visual inputs, makes it difficult to directly adapt existing indoor methods; 2) the lack of data with comprehensive box-caption pair annotations specifically tailored for outdoor scenes. To this end, we introduce the new task of outdoor 3D dense captioning. As input, we assume a LiDAR point cloud and a set of RGB images captured by the panoramic camera rig. The expected output is a set of object boxes with captions. To tackle this task, we propose the TOD3Cap network, which leverages the BEV representation to generate object box proposals and integrates Relation Q-Former with LLaMA-Adapter to generate rich captions for these objects. We also introduce the TOD3Cap dataset, the largest one to our knowledge for 3D dense captioning in outdoor scenes, which contains 2.3M descriptions of 64.3K outdoor objects from 850 scenes. Notably, our TOD3Cap network can effectively localize and caption 3D objects in outdoor scenes, which outperforms baseline methods by a significant margin (+9.6 CiDEr@0.5IoU). Code, data, and models are publicly available at https://github.com/jxbbb/TOD3Cap.

Keywords

Cite

@article{arxiv.2403.19589,
  title  = {TOD3Cap: Towards 3D Dense Captioning in Outdoor Scenes},
  author = {Bu Jin and Yupeng Zheng and Pengfei Li and Weize Li and Yuhang Zheng and Sujie Hu and Xinyu Liu and Jinwei Zhu and Zhijie Yan and Haiyang Sun and Kun Zhan and Peng Jia and Xiaoxiao Long and Yilun Chen and Hao Zhao},
  journal= {arXiv preprint arXiv:2403.19589},
  year   = {2024}
}

Comments

Code, data, and models are publicly available at https://github.com/jxbbb/TOD3Cap

R2 v1 2026-06-28T15:37:23.424Z