Recently, significant progress has been made in the research of 3D object detection. However, most prior studies have focused on the utilization of center-based or anchor-based label assignment schemes. Alternative label assignment strategies remain unexplored in 3D object detection. We find that the center-based label assignment often fails to generate sufficient positive samples for training, while the anchor-based label assignment tends to encounter an imbalanced issue when handling objects of varying scales. To solve these issues, we introduce a dynamic cross label assignment (DCLA) scheme, which dynamically assigns positive samples for each object from a cross-shaped region, thus providing sufficient and balanced positive samples for training. Furthermore, to address the challenge of accurately regressing objects with varying scales, we put forth a rotation-weighted Intersection over Union (RWIoU) metric to replace the widely used L1 metric in regression loss. Extensive experiments demonstrate the generality and effectiveness of our DCLA and RWIoU-based regression loss. The Code will be available at https://github.com/Say2L/DCDet.git.

近年来，3D物体检测的研究取得了显著进展。然而，大多数现有研究聚焦于基于中心或基于锚点的标签赋值方案的利用。在3D物体检测中，尚未探索其他的标签赋值策略。我们发现，基于中心的标签赋值方法通常在训练时生成不足的正样本，而基于锚点的标签赋值方法在处理不同尺度的物体时往往遇到不平衡问题。为了解决这些问题，我们引入了一种动态交叉标签赋值（DCLA）方案，该方案为每个物体动态地从交叉区域中分配正样本，从而为训练提供足够且平衡的正样本。此外，为了应对准确回归具有不同尺度的物体的挑战，我们提出了一种基于旋转加权交并比（RWIoU）的回归损失指标，以替代广泛使用的L1损失指标。大量实验证明了我们的DCLA和基于RWIoU的回归损失的普适性和有效性。代码可在此网址上获取：https://链接地址

DCDet: 动态基于交叉的3D目标检测器