Organizations: Beijing Institute of Technology · Tsinghua University · China Agricultural University · Beijing Jiaotong University · The Hong Kong Polytechnic University · Li Auto
Multi-task visual anomaly detection is critical for car-related manufacturing quality assessment. However, existing methods remain task-specific, hindered by the absence of a unified benchmark for multi-task evaluation. To fill in this gap, We present the CAD Dataset, a large-scale and comprehensive benchmark designed for car-related multi-task visual anomaly detection. The dataset contains over 100 images crossing 7 vehicle domains and 3 tasks, providing models a comprehensive view for car-related anomaly detection. It is the first car-related anomaly dataset specialized for multi-task learning(MTL), while combining synthesis data augmentation for few-shot anomaly images. We implement a multi-task baseline and conduct extensive empirical studies. Results show MTL promotes task interaction and knowledge transfer, while also exposing challenging conflicts between tasks. The CAD dataset serves as a standardized platform to drive future advances in car-related multi-task visual anomaly detection.
Figures & tables
Figure 1: Overview of the CAD 100K Dataset. The CAD 100K dataset contains over 100 K images crossing 7 domains and 3 tasks, providing a comprehensive view for car-related anomaly detection. It features a multi-task architecture and synthesis data augmentation methods, solves cross-domain problems, supports both supervised and unsupervised learning paradigms, and is compatible with few-shot learning frameworks.
Figure 2: Tasks and structure of the CAD 100K Dataset. CAD 100K adopts a hierarchical domain–system–part anomaly structure to ensure semantic consistency and extensibility across different tasks.
Figure 3: The data composition across domains, tasks, and sources in CAD 100K. All images are in RGB format with various resolutions from 100 × 84 to 4096 × 3072, covering diverse lighting and viewpoints.
Figure 4: Structure of the proposed Baseline.
Backbone Type
Backbone Size
Method
Cls. Acc (%)
Det. mAP (%)
Seg. mIoU (%)
DINOv3 (ViT)
Smallplus
Single
98.40
59.20
72.80
Base
98.40
58.90
70.93
Adaptive
98.40
57.80
71.88
Base
Single
100.00
59.40
72.42
Base
98.80
58.20
71.95
Adaptive
99.10
58.90
72.25
Table 1: Comprehensive performance comparison on public car-related benchmarks across different backbone architectures, scales, and training paradigms. Results show classification accuracy (Cls. Acc), detection mAP (Det. mAP), and segmentation mIoU (Seg. mIoU). Bold indicates the best performance within each backbone size and architecture combination.
Backbone
Method
Cls. Acc (%)
Det. mAP (%)
Seg. mIoU (%)
DINOv3-Splus
Base
92.98
55.20
56.84
Adaptive
89.47
59.60
57.19
ConvNeXt-S
Base
92.10
59.10
52.20
Adaptive
90.10
60.10
52.77
Table 2: Performance comparison on three types of tasks in the CAD 100K dataset configurations: ConvNeXt-S with base and adaptive MTL, and DINOv3-Splus with base and adaptive MTL. Results demonstrate the effectiveness of our adaptive strategy across different backbone architectures.
Appendix figures & tables10 assets
Supplementary material from the paper’s appendix.
Appendix
Figure B1 : The Exterior Domain Subset Supporting both Detection and Segmentation in the CAD 100K Dataset. This subset contains various exterior anomalies with both bounding box and pixel-level mask annotations.
Figure B2 : The Interior and General Domain Detection Subset in the CAD 100K Dataset. Examples include interior component defects and general cross-system anomalies with detection annotations.
Figure B3 : The Chassis Domain Classification Subset in the CAD 100K Dataset. Covering suspension, brake, and tire systems with various anomaly types.
Figure B4 : The Engine Domain Classification Subset in the CAD 100K Dataset. Featuring engine components, fluid systems, and mechanical parts.
Figure B5 : The Electrical Domain Classification Subset in the CAD 100K Dataset. Including battery systems, wiring harnesses, and electronic components.
Figure B6 : The EV-specific Domain Classification Subset in the CAD 100K Dataset. Specialized components for electric vehicles including high-voltage systems and charging infrastructure.
Model
Interior
General
Exterior
AP
AP 50
AP 75
AR
AP
AP 50
AP 75
AR
AP
AP 50
AP 75
AR
DINOv3-Splus
48.0
79.9
46.7
61.0
62.4
91.2
65.88
68.9
45.1
66.9
45.2
54.5
ConvNeXt-S
46.9
76.1
46.6
61.8
64.8
92.8
72.3
72.4
51.0
72.0
54.4
57.6
Appendix
Table B1 : Detection Performance Comparison Across Vehicle Domains . Models are evaluated on three vehicle domains (Interior, General, Exterior) using standard COCO metrics including AP at different IoU thresholds and AR.
Model
Chassis
Engine
Electric
EV-specific
Acc@1
Acc@5
Acc@1
Acc@5
Acc@1
Acc@5
Acc@1
Acc@5
DINOv3-Splus
91.2
100.0
90.1
100.0
93.5
99.1
97.9
100.0
ConvNeXt-S
90.4
100.0
93.4
100.0
93.5
100.0
100.0
100.0
Appendix
Table B2 : Classification Performance Across Vehicle Component Domains . Models are evaluated on four vehicle component domains using top-1 and top-5 accuracy metrics.
Model
Car Exterior Anomalies
Car Parts Segmentation
mIoU
mFscore
mPrec
mRecall
mIoU
mFscore
mPrec
mRecall
DINOv3-Splus
54.9
67.0
85.7
58.1
72.0
81.7
81.9
81.9
ConvNeXt-S
52.4
65.1
90.1
54.4
72.9
82.4
82.7
82.6
Appendix
Table B3 : Segmentation Performance Comparison . Models are evaluated on both car exterior anomalies segmentation and car parts segmentation tasks using mIoU, mFscore, and mPrecision metrics.
Model
Method
Cls. Acc (%)
Det. mAP (%)
Seg. mIoU (%)
DINOv3-Splus
Single
98.40
59.20
72.80
Base-MTL
98.40
58.90
70.93
Adaptive-MTL
98.40
57.80
71.88
ConvNeXt-S
Single
98.80
58.80
72.80
Base-MTL
98.80
58.60
71.12
Adaptive-MTL
98.80
59.10
71.82
Appendix
Table B4 : Multi-task Learning Performance Comparison on Public Benchmarks . Models are evaluated across classification, detection, and segmentation tasks using single-task learning (STL), base multi-task learning (Base-MTL), and adaptive multi-task learning (Adaptive-MTL) approaches.
The progress of Anomaly Detection (AD) in safety-critical domains, such as transportation, is severely constrained by the lack of large-scale, real-world benchmarks. To address this, we introduce EngineAD, a novel, multivariate dataset comprising high-resolution sensor telemetry collected from a fleet of 25 commercial vehicles over a six-month period. Unlike synthetic datasets, EngineAD features authentic operational data labeled with expert annotations, distinguishing normal states from subtle indicators of incipient engine faults. We preprocess the data into 300-timestep segments of 8 principal components and establish an initial benchmark using nine diverse one-class anomaly detection models. Our experiments reveal significant performance variability across the vehicle fleet, underscoring the challenge of cross-vehicle generalization. Furthermore, our findings corroborate recent literature, showing that simple classical methods (e.g., K-Means and One-Class SVM) are often highly competitive with, or superior to, deep learning approaches in this segment-based evaluation. By publicly releasing EngineAD, we aim to provide a realistic, challenging resource for developing robust and field-deployable anomaly detection and anomaly prediction solutions for the automotive industry.
Hadi Hojjati, Christopher Roth, Rory Woods +2
Department of Electrical and Computer Engineering, McGill University, CA · MILA - Quebec AI Institute, CA · Preteckt Inc., Hamilton, ON, Canada
Industrial anomaly detection is critical for manufacturing quality control, yet existing datasets mainly focus on static images or sparse views, which do not fully reflect continuous inspection processes in real industrial scenarios. We introduce MMVIAD (Multi-view Multi-task Video Industrial Anomaly Detection), to the best of our knowledge the first continuous multi-view video dataset for industrial anomaly detection and understanding, together with a benchmark for multi-task evaluation. MMVIAD contains object-centric 2-second inspection clips with approximately 120 degrees of camera motion, covering 48 object categories, 14 environments, and 6 structural anomaly types. It supports anomaly detection, defect classification, object classification, and anomaly visible-time localization. Systematic evaluations on MMVIAD show that current commercial and open-source video MLLMs remain far below human performance, especially for fine-grained defect recognition and temporal grounding. To improve transferable anomaly understanding, we further develop a two-stage post-training pipeline where PS-SFT (Perception-Structured Supervised Fine-Tuning) initializes perception-structured reasoning and VISTA-GRPO (Visibility-grounded Industrial Structured Temporal Anomaly Group Relative Policy Optimization) refines the model with semantic-gated defect reward and visibility-aware temporal reward, producing the final model VISTA. On MMVIAD-Unseen, VISTA improves the base model's average score across the four tasks from 45.0 to 57.5, surpassing GPT-5.4. Source code is available at https://github.com/Georgekeepmoving/MMVIAD.
Xiran Zhao, Jing Jin, Yan Bai +6
ShanghaiTech University · Tsinghua University · Meituan Inc. +1
Multimodal Large Language Models (MLLMs) have achieved impressive success in natural visual understanding, yet they consistently underperform in industrial anomaly detection (IAD). This is because MLLMs trained mostly on general web data differ significantly from industrial images. Moreover, they encode each image independently and can only compare images in the language space, making them insensitive to subtle visual differences that are key to IAD. To tackle these issues, we present AD-Copilot, an interactive MLLM specialized for IAD via visual in-context comparison. We first design a novel data curation pipeline to mine inspection knowledge from sparsely labeled industrial images and generate precise samples for captioning, VQA, and defect localization, yielding a large-scale multimodal dataset Chat-AD rich in semantic signals for IAD. On this foundation, AD-Copilot incorporates a novel Comparison Encoder that employs cross-attention between paired image features to enhance multi-image fine-grained perception, and is trained with a multi-stage strategy that incorporates domain knowledge and gradually enhances IAD skills. In addition, we introduce MMAD-BBox, an extended benchmark for anomaly localization with bounding-box-based evaluation. The experiments show that AD-Copilot achieves 82.3% accuracy on the MMAD benchmark, outperforming all other models without any data leakage. In the MMAD-BBox test, it achieves a maximum improvement of 3.35× over the baseline. AD-Copilot also exhibits excellent generalization of its performance gains across other specialized and general-purpose benchmarks. Remarkably, AD-Copilot surpasses human expert-level performance on several IAD tasks, demonstrating its potential as a reliable assistant for real-world industrial inspection. All datasets and models will be released for the broader benefit of the community.
Xi Jiang, Yue Guo, Jian Li +7
Department of Computer Science and Engineering, Southern University of Science and Technology, Shenzhen, China · Macau University of Science and Technology, Macau, China · Tencent YouTu Lab, Shenzhen and Shanghai, China +3