dkalsan/FLEDGE

Dataset Summary

This dataset contains generated images for semantic segmentation targeting the Cityscapes and ACDC domains. The images are produced from five source datasets using the method described in: A Framework for Low-Effort Training Data Generation for Urban Semantic Segmentation.

Technical Specifications

• Subset Selection: To preserve storage space, we release the top 3 generated images per original source image, selected based on our proposed MCOC score.
• Label Mapping: All masks follow the standard Cityscapes 19-class format.
• Resolution: 512 x 1024 (Height x Width).
• Format: Images and masks are provided in .png format.

---

Dataset Statistics

The following table reflects the number of source images used to generate the target domain data.

Source Domain	Image Count	Status
GTA	24,966	Available
UrbanSyn	7,539	Available
VEIS	3,018	Available
SHIFT	3,000	Available
Synscapes	0	Restricted

Note on Synscapes: Due to licensing restrictions, we are unable to release the generated Synscapes data. The folders contain the original license file for reference but do not include image data.

---

Dataset Structure

The data is organized by <Target_Domain>/<Source_Domain>/.

<Target_Domain>/
└── <Source_Domain>/
    ├── images/         # Top 3 generated images per source (MCOC ranked)
    ├── original_tid/   # Original source segmentation maps
    ├── hrda_tid/       # HRDA pseudo-labels
    ├── splits/         # .txt files for training loading
    └── LICENSE         # Original source dataset license

---

Usage Example

Example data loading scripts that utilize the provided .txt split files are available in our official GitHub repository: github.com/vislearn/FLEDGE

---

Citation

@misc{kalsan2025fledge,
  title={A Framework for Low-Effort Training Data Generation for Urban Semantic Segmentation}, 
  author={Damjan Kalšan and Denis Zavadski and Tim Küchler and Haebom Lee and Stefan Roth and Carsten Rother},
  year={2025},
  eprint={2510.11567},
  archivePrefix={arXiv},
  primaryClass={cs.CV}
}