DLR Institute of Transportation Systems
Published September 30, 2026 | Version 1.0.0
Dataset Open

TRails: Top Rail Segmentation

Authors/Creators

  • 1. ROR icon Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR)
  • 2. DLR

Description

Description

The Top-view Rail Segmentation (TRails) dataset is a dedicated benchmark containing high-precision, pixel-accurate semantic segmentation masks for downward-facing railway track inspection. Captured at 2 m intervals using the rear-mounted TrackScan camera system (1280×720 resolution)  on the LEONARDO platform (https://struktonrail.com/innovations/leonardo-inspection-train/). TRails specifically targets structural track complexity, varying ballast conditions, and safety-critical switch assemblies.
The dataset comprises 1,357 pixel-annotated images categorized into four structural track classes:
  1. Regular Rails — 1026 images
  2. Hard Examples (corner cases of regular rails) — 12 images
  3. Switch Rails — 223 images
  4. Frogs — 96 images

Data Format & Organization:

  • Images/: High-resolution raw RGB images in .jpg format (1280 x 720).
  • Labels/Masks/: Pixel-level ground-truth semantic segmentation masks in .png format. 
  • Labels/JSONs/: Object-level bounding annotations and metadata in .json format.

Primary Applications:
This benchmark is curated to advance intelligent railway perception, including:

  • Thin-structure semantic segmentation and boundary delineation

  • Track gauge metrology and switch-blade gap verification

  • Region of Interest (ROI) isolation for downstream unsupervised defect detection

  • High-definition railway digital twin and map generation

Acknowledgements

Funded by the European Union. Views and opinion expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or Europe’s Rail Joint Undertaking. Neither the European Union nor the granting authority can be held responsible for them. The project FP3-IAM4Rail (Grant Agreement No. 101101966) is supported by the Europe's Rail Joint Undertaking and its members.

License

The license is specified in the License.txt file.

Files

TRails_Dataset.zip

Files (64.8 MB)

Name Size
md5:1e30fc4bb116be9c5150fe1d5c73924d
64.8 MB Preview Download

Additional details

Identifiers

DOI
10.5281/zenodo.19553375

Funding

European Commission
FP3 - IAM4RAIL - Europe's Rail Flagship Project 3 - Holistic and Integrated Asset Management for Europe's RAIL System 101101966

Dates

Submitted
2026-09-25
Image dataset containing semantic lables of rails from top-view.