Using Lower-Bound Representations for Trajectory Similarity Learning
- URL: http://arxiv.org/abs/2608.01039v1
- Date: Sun, 02 Aug 2026 06:53:49 GMT
- Title: Using Lower-Bound Representations for Trajectory Similarity Learning
- Abstract summary: Trajectory similarity learning is fundamental to efficient trajectory retrieval under complex distance measures.<n>We propose LB-TrajRep, a unified lower-bound representation framework independent of deep neural embeddings.
- Score: 17.84474521141356
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Trajectory similarity learning is fundamental to efficient trajectory retrieval under complex distance measures. Existing learning-based methods typically rely on embeddings trained to approximate trajectory distances or rankings, but they often lack guarantees with respect to the original distances, exhibit unstable performance across distance measures, and incur substantial training costs. We revisit trajectory similarity learning from a lower-bound representation perspective and propose LB-TrajRep, a unified lower-bound representation framework independent of deep neural embeddings. This framework constructs single-vector representations from a set of lower-bound components, enabling admissible and interpretable lower bounds for multiple classical trajectory distances, including Dynamic Time Warping (DTW), Hausdorff distance, and Discrete Fréchet Distance (DFD). Within this framework, we instantiate point-pivot components, which naturally support both metric and non-metric distances and remain compatible with standard vector-based retrieval pipelines. To improve ranking quality, we develop two data-driven pivot selection strategies that explicitly optimize lower-bound tightness and prioritize hard near-neighbor trajectory pairs, respectively. Extensive experiments on real-world trajectory datasets show that the proposed lower-bound representations are able to consistently outperform state-of-the-art neural trajectory embeddings across diverse distance measures, improving top-$k$ ranking accuracy by up to 20\%--60\% on the Hausdorff distance and DFD and by 15\%--40\% on DTW.
Related papers
- Event-Based Motion Estimation via Oriented Distance Fields [55.23416502666468]
Event-based motion estimation is central to tasks that demand high temporal resolution and robustness to fast motion.<n>We propose Oriented Distance Field Motion Estimation (ODF Motion Estimation), which replaces this optimization with a single averaging step over a precomputed field of event distance vectors.<n>On public and self-collected datasets, ODF motion estimation reaches sub-pixel accuracy at the lowest latency among compared methods.
arXiv Detail & Related papers (2026-08-25T08:27:42Z) - FoundationGeo: Learning Spatial Pixel-Wise Fields for Monocular Metric Geometry [52.232826445242644]
FoundationGeo bridges relative and metric prediction via spatial calibration and principled data design.<n>Stage 1 learns a high-fidelity, affine-invariant geometry model by initializing with DINOv3.<n>Stage 2 moves beyond global scaling by introducing pixel-wise calibration fields for metric estimation.
arXiv Detail & Related papers (2026-07-13T14:10:01Z) - TopoCurate:Modeling Interaction Topology for Tool-Use Agent Training [53.93696896939915]
Training tool-use agents typically rely on Supervised Fine-Tuning (SFT) on successful trajectories and Reinforcement Learning (RL) on pass-rate-selected tasks.<n>We propose TopoCurate, an interaction-aware framework that projects multi-trial rollouts from the same task into a unified semantic quotient topology.<n>TopoCurate achieves consistent gains of 4.2% (SFT) and 6.9% (RL) over state-of-the-art baselines.
arXiv Detail & Related papers (2026-03-02T10:38:54Z) - Region-Point Joint Representation for Effective Trajectory Similarity Learning [25.664203648334563]
textbfRePo is a novel method that encodes textbfRegion-wise and textbfPoint-wise features to capture both spatial context and fine-grained moving patterns.<n>Experiment results show that RePo achieves an average accuracy improvement of 22.2% over SOTA baselines.
arXiv Detail & Related papers (2025-11-17T08:28:18Z) - DELTAv2: Accelerating Dense 3D Tracking [79.63990337419514]
We propose a novel algorithm for accelerating dense long-term 3D point tracking in videos.<n>We introduce a coarse-to-fine strategy that begins tracking with a small subset of points and progressively expands the set of tracked trajectories.<n>The newly added trajectories are using a learnable module, which is trained end-to-end alongside the tracking network.
arXiv Detail & Related papers (2025-08-02T03:15:47Z) - Contrast & Compress: Learning Lightweight Embeddings for Short Trajectories [11.6132604160666]
We propose a novel framework for learning fixed-dimensional embeddings for short trajectories by leveraging a Transformer encoder.<n>We analyze the influence of Cosine and FFT-based similarity metrics within the contrastive learning paradigm.<n>Our empirical evaluation on the Argoverse 2 dataset demonstrates that embeddings shaped by Cosine similarity objectives yield superior clustering of trajectories.
arXiv Detail & Related papers (2025-06-03T07:53:04Z) - GeoMM: On Geodesic Perspective for Multi-modal Learning [55.41612200877861]
This paper introduces geodesic distance as a novel distance metric in multi-modal learning for the first time.<n>Our approach incorporates a comprehensive series of strategies to adapt geodesic distance for the current multimodal learning.
arXiv Detail & Related papers (2025-05-16T13:12:41Z) - T-JEPA: A Joint-Embedding Predictive Architecture for Trajectory Similarity Computation [6.844357745770191]
Trajectory similarity computation is an essential technique for analyzing moving patterns of spatial data across various applications.
We propose T-JEPA, a self-supervised trajectory similarity method employing Joint-Embedding Predictive Architecture (JEPA) to enhance trajectory representation learning.
arXiv Detail & Related papers (2024-06-13T09:51:51Z) - Contrastive Trajectory Similarity Learning with Dual-Feature Attention [24.445998309807965]
Tray similarity measures act as query predicates in trajectory databases.
We propose a contrastive learning-based trajectory modelling method named TrajCL.
TrajCL is consistently and significantly more accurate and faster than the state-of-the-art trajectory similarity measures.
arXiv Detail & Related papers (2022-10-11T05:25:14Z) - Ranking Distance Calibration for Cross-Domain Few-Shot Learning [91.22458739205766]
Recent progress in few-shot learning promotes a more realistic cross-domain setting.
Due to the domain gap and disjoint label spaces between source and target datasets, their shared knowledge is extremely limited.
We employ a re-ranking process for calibrating a target distance matrix by discovering the reciprocal k-nearest neighbours within the task.
arXiv Detail & Related papers (2021-12-01T03:36:58Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.