Low-dimensional re-ID features are compact numerical embeddings that capture the visual appearance of an object to track and re-identify it across video frames or camera views. Unlike traditional re-identification systems that generate high-dimensional feature vectors, these compact embeddings intentionally restrict feature dimensionality to facilitate joint object detection and re-identification within a single unified network. This lower dimensionality balances the learning dynamics between the detection and tracking branches during multi-task training, reduces computational complexity and memory consumption for real-time data association, and helps prevent overfitting on small identity datasets while retaining sufficient discriminative detail.