STRIDE-QA: Visual Question Answering Dataset for Spatiotemporal Reasoning in Urban Driving Scenes¶
Conference: AAAI 2026 Oral
arXiv: 2508.10427
Code: turingmotors/stride-qa
Area: Autonomous Driving / Visual Question Answering / Spatiotemporal Reasoning
Keywords: VQA, spatiotemporal reasoning, ego-centric perspective, 3D annotation, VLM fine-tuning
TL;DR¶
This paper constructs STRIDE-QA, the largest spatiotemporal reasoning VQA dataset in autonomous driving (270K frames, 16M QA pairs), defines three categories of spatiotemporal reasoning tasks (object-centric spatial / ego-centric spatial / ego-centric spatiotemporal), and demonstrates that fine-tuning a VLM raises localization success rate from near zero to 55% and temporal localization consistency from 0 to 28.4%.
Background & Motivation¶
Background: VLMs (e.g., GPT-4o, Qwen2.5-VL) have been applied to autonomous driving scene understanding and decision support. Existing driving VQA datasets include nuScenes-QA (460K QA pairs) and nuPlanQA (1M QA pairs), among others.
Limitations of Prior Work: Existing VLMs are trained on static web imageโtext pairs and lack precise spatiotemporal reasoning capabilities. Prior driving VQA datasets either support only object-centric perspectives, lack temporally aligned 3D annotations, or are limited in scale.
Key Challenge: No existing dataset simultaneously supports all three task typesโobject-centric spatial reasoning, ego-centric spatial reasoning, and ego-centric spatiotemporal reasoning (including future prediction). Existing methods score near zero on spatiotemporal prediction consistency.
Key Insight: The authors leverage 100 hours of driving data collected in Tokyo and construct a large-scale spatiotemporal reasoning VQA dataset of 16M QA pairs via a fully automated annotation pipeline (BEVFusion 3D detection + PubTracker tracking + SAM 2.1 segmentation + visibility filtering).
Core Idea: Provide VLMs with large-scale, physically grounded spatiotemporal supervision signals, enabling a capability leap from passive scene description to future motion prediction.
Sensor Configuration: 64-channel LiDAR + 6 cameras (front/rear 2880ร1860, side 1920ร1240, 60ยฐ FOV, 360ยฐ coverage) + IMU + RTK-GNSS, with 20-second clip segmentation.
Method¶
Overall Architecture¶
Multi-sensor driving data (6 cameras + 64-beam LiDAR, 2 Hz synchronization) โ Fully automated annotation pipeline โ QA pair generation โ VLM fine-tuning. The annotation pipeline comprises seven modules: keyframe sampling, 3D object detection, multi-object tracking, attribute extraction, semantic segmentation, visibility filtering, and question generation.
Dataset statistics: the training set contains 5.30M qualitative QA pairs + 10.17M quantitative QA pairs; the validation set contains 0.28M qualitative + 0.69M quantitative. The evaluation set consists of 409 scene groups with 5,317 QA pairs covering 6 types of dynamic interaction scenarios.
Key Design 1: Three VQA Task Categories¶
- Object-centric Spatial QA: Single-frame tasks judging spatial relationships between two non-ego agents (qualitative questions such as relative position; quantitative questions such as "distance 1.53 m").
- Ego-centric Spatial QA: Single-frame tasks describing an agent's distance, heading, and size relative to the ego vehicle.
- Ego-centric Spatiotemporal QA: Given 4 frames of context sampled at 2 Hz (\(t \in \{-1.5, -1.0, -0.5, 0\}\) s), the model predicts the target agent's distance, heading angle, and velocity at future steps \(t \in \{1, 2, 3\}\) s.
Key Design 2: Fully Automated Annotation Pipeline¶
Seven modular components: (1) 1 Hz keyframe sampling (2โ17 s window per clip); (2) BEVFusion LiDARโcamera fusion 3D detection (45 object classes, mAP = 0.701, position error only 13.6 cm); (3) PubTracker point-based 3D tracking (no appearance features required, AMOTA = 0.676); (4) attribute extractor (Euclidean distance, heading angle, and velocity in the ego coordinate frame); (5) SAM 2.1 Large segmentation (per-instance 2D masks); (6) visibility filtering (triple filter: IoU > 0.3, coverage > 0.8, SAM confidence > 0.8); (7) template-based QA generation (Region [X] reference identifiers).
Key Design 3: Evaluation Metric Framework¶
- LSR (Localization Success Rate): A prediction is deemed successful when distance error < ยฑ25% of the GT value and heading error < ยฑ10ยฐ.
- MLSR (Mean LSR): Sequence-level mean of LSR, measuring temporal stability.
- TLC (Temporal Localization Consistency): A strict consistency measure requiring success at all four time steps.
Loss & Training¶
Fine-tuning uses LoRA (rank = 16, alpha = 32, dropout = 0.05), trained for 2 epochs on 16 H100 GPUs. Learning rates are 5e-5 (LLM) / 2e-6 (visual encoder) / 1e-5 (projection head), with a global batch size of 64. The optimizer is AdamW (\(\beta_1 = 0.9\), \(\beta_2 = 0.999\), weight decay = 0.1) with a cosine scheduler and 5% warmup. Inference temperature is set to 0 to ensure deterministic outputs. Input consists of 4 front-view frames (532ร336 resolution) annotated with Region ID masks generated via the Set-of-Mark method.
Experiments¶
Main Results: STRIDE-QA Bench Spatiotemporal Reasoning¶
| Model | LSR@0s | LSR@1s | LSR@2s | LSR@3s | MLSR | TLC |
|---|---|---|---|---|---|---|
| GPT-4o | 18.1 | 6.6 | 6.1 | 7.6 | 9.6 | 0.7 |
| GPT-4o mini | 4.6 | 2.0 | 0.7 | 0.7 | 2.0 | 0.0 |
| Qwen2.5-VL-7B | 1.0 | 3.4 | 4.4 | 1.0 | 2.4 | 0.0 |
| SpatialRGPT-8B | 0.5 | 0.2 | 0.2 | 0.0 | 0.2 | 0.0 |
| Cosmos-Reason1-7B | 1.5 | 3.2 | 2.0 | 1.5 | 2.0 | 0.0 |
| STRIDE-Qwen2.5-VL-7B | 96.3 | 46.2 | 38.4 | 38.9 | 55.0 | 28.4 |
| STRIDE-Cosmos-Reason1-7B | 96.8 | 43.5 | 37.4 | 36.2 | 53.5 | 25.4 |
Ablation Study: SpatialRGPT-Bench Spatial Reasoning¶
| Model | Orig. Qual.โ | Orig. Quant.โ | Obj Spatial Quant.โ | Ego Spatial Qual.โ | Ego Spatial Quant.โ |
|---|---|---|---|---|---|
| GPT-4o | 80.5 | 32.5 | 39.4 | 55.7 | 27.7 |
| Qwen2.5-VL-7B | 67.2 | 24.4 | 12.8 | 47.1 | 29.3 |
| STRIDE-Qwen2.5-VL-7B | 69.5 | 37.5 | 61.5 | 77.9 | 70.3 |
| STRIDE-Cosmos-Reason1-7B | 71.1 | 30.0 | 58.7 | 79.9 | 68.9 |
Key Findings¶
- General-purpose VLMs almost completely fail at spatiotemporal reasoning: All baseline models achieve TLC โ 0, indicating a complete lack of temporally consistent reasoning capability.
- Fine-tuning yields dramatic improvements: STRIDE-Qwen2.5-VL-7B improves LSR@0s from 1.0% to 96.3% (a 96ร gain), with MLSR reaching 55.0.
- Out-of-view prediction is the primary bottleneck: LSR degrades gradually for the Maintain State scenario (target remains in view), but drops sharply for out-of-view (OOV) scenarios such as Oncoming Pass, which is the primary reason TLC reaches only 28.4%.
- Cross-domain transfer is effective: On the external SpatialRGPT-Bench, ego-centric spatial quantitative accuracy improves from 29.3% to 70.3% (+41 pt).
- Baseline model behavior analysis: Baseline VLMs produce sparse predictions with systematic biases, repeatedly generating similar erroneous guesses, indicating reliance on simple memorized behaviors rather than visual context-based reasoning.
- Significant variation across six dynamic scene types: The LSR decay patterns of Oncoming Pass (OOV rate 100%) and Maintain State (OOV rate 5%) are sharply contrasting, confirming that OOV is the primary driver of performance degradation.
- Rich dataset statistics: The vehicle class dominates (440K instances), with adequate coverage of pedestrians (139K) and large vehicles (119K).
Highlights & Insights¶
- 16M QA pairs ร 270K frames: currently the largest-scale dataset for spatiotemporal reasoning VQA in autonomous driving.
- The first unified framework supporting all three reasoning categories: object-centric spatial, ego-centric spatial, and ego-centric spatiotemporal.
- A fully automated annotation pipeline with 3D detection error of only 13.6 cm, scalable to larger datasets.
- A three-tier LSR/MLSR/TLC metric hierarchy that precisely quantifies each dimension of VLM spatiotemporal reasoning capability.
- Data collection covers diverse Tokyo scenarios: traffic congestion, construction zones, and pedestrian-dense intersections.
- Comprehensive privacy protection: Dashcam Anonymizer automatically blurs faces and license plates.
Limitations & Future Work¶
- Single front-view evaluation: Only the front-view camera (60ยฐ FOV) is used; prediction capability drops sharply when targets leave the field of view, and multi-camera fusion remains unexplored.
- LoRA-only fine-tuning: Due to compute constraints, full-parameter fine-tuning performance upper bounds have not been investigated.
- No downstream task evaluation: The benefit of spatiotemporal reasoning capability for safety-critical tasks such as motion planning and behavior prediction has not been verified.
- No cross-dataset generalization: As the first spatiotemporal reasoning benchmark of its kind, no comparable public dataset is available for cross-validation.
- Limitations of template-based QA: QA pairs are generated from templates and lack natural language diversity, potentially limiting generalization of the VLM's language understanding.
- Relatively large velocity estimation error: The detection pipeline achieves mAVE = 1.28 m/s, introducing non-negligible noise into QA quality on the velocity dimension.
Related Work & Insights¶
- Spatially-aware VLMs: SpatialVLM (CVPR 2024), Spatial-RGPT (NeurIPS 2024) โ address spatial reasoning in static scenes, lacking the temporal dimension.
- Driving VQA datasets: nuScenes-QA (AAAI 2024, 460K pairs), nuPlanQA (2025, 1M pairs), TUMTraffic-VideoQA (ICML 2025, 87.3K) โ inferior to STRIDE-QA in both scale and task coverage.
- Driving VLMs: DriveLM (ECCV 2024), Senna-VLM, Cosmos-Reason1-7B (NVIDIA 2025) โ designed for scene understanding and high-level decision making.
- ToD3Cap / NuPrompt: Focus on ego-centric spatial description and object referring, but lack spatiotemporal prediction tasks.
- Refer-KITTI: Only 6 hours and 818 referring expressions โ far insufficient in scale.
Rating¶
โญโญโญโญ โ The dataset scale and annotation pipeline quality are solid, and the three-task taxonomy is clearly defined with practical significance. The core findingsโthat general-purpose VLMs score near zero on spatiotemporal reasoning while fine-tuning yields substantial gainsโprovide important reference value. Limitations include the single front-view evaluation setup and the absence of validation on downstream planning tasks.