  The new trend in multi-object tracking task is to track objects of interest
using natural language. However, the scarcity of paired prompt-instance data
hinders its progress. To address this challenge, we propose a high-quality yet
low-cost data generation method base on Unreal Engine 5 and construct a
brand-new benchmark dataset, named Refer-UE-City, which primarily includes
scenes from intersection surveillance videos, detailing the appearance and
actions of people and vehicles. Specifically, it provides 14 videos with a
total of 714 expressions, and is comparable in scale to the Refer-KITTI
dataset. Additionally, we propose a multi-level semantic-guided multi-object
framework called MLS-Track, where the interaction between the model and text is
enhanced layer by layer through the introduction of Semantic Guidance Module
(SGM) and Semantic Correlation Branch (SCB). Extensive experiments on
Refer-UE-City and Refer-KITTI datasets demonstrate the effectiveness of our
proposed framework and it achieves state-of-the-art performance. Code and
datatsets will be available.
