VRAR: Video-Radar Automatic Registration Method Based on Trajectory Spatiotemporal Features and Bidirectional Mapping

Automating video and radar spatial registration without sensor layout constraints is crucial for enhancing the flexibility of perception systems. However, this remains challenging due to the lack of effective approaches for constructing and utilizing matching information between heterogeneous sensors. Existing methods rely on human intervention or prior knowledge, making it difficult to achieve true automation. Consequently, establishing a registration model that automatically extracts matching information from heterogeneous sensor data remains a key challenge. To address these issues, we propose a novel Video-Radar Automatic Registration (VRAR) method based on vehicle trajectory spatiotemporal feature encoding and a bidirectional mapping network. We first establish a unified representation for heterogeneous sensor data by encoding spatiotemporal features of vehicle trajectories. Based on this, we automatically extract a large number of high-quality matching points from synchronized trajectory pairs using a frame synchronization strategy. Subsequently, we utilize the proposed Video-Radar Bidirectional Mapping Network to process these matching points. This network learns the bidirectional mapping between the two sensor modalities, extending the alignment from discrete local observation points to the entire observable space. Experimental results demonstrate that the VRAR method exhibits significant performance advantages in various traffic scenarios, verifying its effectiveness and generalizability. This capability of automated and adaptive registration highlights the method’s potential for broader applications in heterogeneous sensor integration.