Open-Scenario Domain Adaptive Object Detection in Autonomous Driving

Existing domain adaptive object detection algorithms (DAOD) have demonstrated their effectiveness in discriminating and localizing objects across scenarios. However, these algorithms typically assume a single source and target domain for adaptation, which is not representative of the more complex data distributions in practice. To address this issue, we propose a novel Open-Scenario Domain Adaptive Object Detection (OSDA), which leverages multiple source and target domains for more practical and effective domain adaptation. We are the first to increase the granularity of the background category by building the foundation model using contrastive vision-language pre-training in an open-scenario setting for better distinguishing foreground and background, which is under-explored in previous studies. The performance gains by introducing the pre-training have been observed and have validated the model's ability to detect objects across domains. To further fine-tune the model for domain-specific object detection, we propose a hierarchical feature alignment strategy to obtain a better common feature space among the various source and target domains. In the case of multi-source domains, the cross-reconstruction framework is introduced for learning more domain invariances. The proposed method is able to alleviate knowledge forgetting without any additional computational costs. Extensive experiments across different scenarios demonstrate the effectiveness of the proposed model.