Contextual Object Detection with Multimodal Large Language Models

Yuhang Zang  Wei Li  Jun Han  Kaiyang Zhou 
Chen Change Loy 

S-Lab, Nanyang Technological University

Currently, we only offer the Hugging Face demo code. The CODE dataset and training scripts will be made available once this paper is accepted.

🌟 Contextual Object Detection

Recent Multimodal Large Language Models (MLLMs) are remarkable in vision-language tasks, such as image captioning and question answering, but lack the essential perception ability, i.e., object detection. In this work, we address this limitation by introducing a novel research problem of contextual object detection--understanding visible objects within different human-AI interactive contexts. Three representative scenarios are investigated, including the language cloze test, visual captioning, and question answering.

Comparison with Related Works

Task	Language Input	Output(s)	Remark
Object Detection	✗	box, class label	pre-defined class labels
Open-Vocabulary Object Detection	(optional) class names for CLIP	box, class label	pre-defined class labels
Referring Expression Comprehension	complete referring expression	box that expression refers to	/
Contextual Cloze Test (ours)	incomplete expression, object names are masked	{box, name} to complete the mask	name could be most valid English word
Image Captioning	✗	language caption	/
Contextual Captioning (ours)	✗	language caption, box	/
Visual Question Answering	language question	language answer	/
Contextual QA (ours)	language question	language question, box	/

😎 Method

We present ContextDET, a novel generate-then-detect framework, specialized for contextual object detection. ContextDET is end-to-end and consists of three key architectural components:

1. a visual encoder that extracts high-level image representations and computes visual tokens,
2. a pre-trained LLM that decodes multimodal contextual tokens with a task-related multimodal prefix, and
3. a visual decoder that predicts matching scores and bounding boxes for conditional queries linked to contextual object words.

The new generate-then-detect framework enables us to detect object words within human vocabulary.

🥰 Qualitative Examples

💻 Try Demo

🤗 You can try our demo on HuggingFace spaces. To avoid waiting in the queue and speed up your inference, consider duplicating the space and use GPU resources.

🤗 If you want to try the demo on your own computer with GPU, follow these steps

1. Install the required python packages:

pip install -r requirements.txt

2. Download the checkpoint file from the following URL and save it in your local directory.
3. Now, you're ready to run the demo. Execute the following command:

python app.py

You are expected to see the following web page:

📝 Citation

We would be grateful if you consider citing our work if you find it useful:

@article{zang2023contextual,
  author = {Zang, Yuhang and Li, Wei and Han, Jun and Zhou, Kaiyang and Loy, Chen Change},
  title = {Contextual Object Detection with Multimodal Large Language Models},
  journal = {arXiv preprint arXiv:2305.18279},
  year = {2023}
}

📋 Liscense

This project is licensed under S-Lab License 1.0. Redistribution and use for non-commercial purposes should follow this license.

😃 Acknowledgement

We acknowledge the use of the following public code in this project: ¹DETR, ²Deformable DETR, ³DETA, ⁴OV DETR, ⁵BLIP2.

📧 Contact

If you have any questions, please feel free to contact Yuhang Zang (zang0012 AT ntu.edu.sg).