Vehicle Re-Identification (Re-ID) aims to identify the same vehicle across different cameras, hence plays an important role in modern traffic management systems. The technical challenges require the algorithms must be robust in different views, resolution, occlusion and illumination conditions. In this paper, we first analyze the main factors hindering the Vehicle Re-ID performance. We then present our solutions, specifically targeting the dataset Track 2 of the 5th AI City Challenge, including (1) reducing the domain gap between real and synthetic data, (2) network modification by stacking multi heads with attention mechanism, (3) adaptive loss weight adjustment. Our method achieves 61.34% mAP on the private CityFlow testset without using external dataset or pseudo labeling, and outperforms all previous works at 87.1% mAP on the Veri benchmark. The code is available at https://github.com/cybercore-co-ltd/track2_aicity_2021.

本文提出了一种针对第五届AI城市挑战赛数据集Track 2的车辆识别方法，包括缩小真实与合成数据之间的域间差距、通过堆叠多个具有注意力机制的网络头进行网络修改、自适应损失权重调整等。该方法在不使用外部数据集或伪标签的情况下，在私人CityFlow测试集上实现61.34％的mAP，并在Veri基准测试中以87.1％的mAP超越了所有先前的工作。

车辆再识别的强基线