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.
Moreover, we present ContextDET, a unified multimodal model that is capable of
end-to-end differentiable modeling of visual-language contexts, so as to
locate, identify, and associate visual objects with language inputs for
human-AI interaction. Our ContextDET involves three key submodels: (i) a visual
encoder for extracting visual representations, (ii) a pre-trained LLM for
multimodal context decoding, and (iii) a visual decoder for predicting bounding
boxes given contextual object words. The new generate-then-detect framework
enables us to detect object words within human vocabulary. Extensive
experiments show the advantages of ContextDET on our proposed CODE benchmark,
open-vocabulary detection, and referring image segmentation. Github:
https://github.com/yuhangzang/ContextDET.Comment: Github: https://github.com/yuhangzang/ContextDET, Project Page:
https://www.mmlab-ntu.com/project/contextdet/index.htm