Skip to main content

Efficient Annotation of Medieval Charters

  • Conference paper
  • First Online:
Document Analysis and Recognition – ICDAR 2023 Workshops (ICDAR 2023)

Abstract

Diplomatics, the analysis of medieval charters, is a major field of research in which paleography is applied. Annotating data, if performed by laymen, needs validation and correction by experts. In this paper, we propose an effective and efficient annotation approach for charter segmentation, essentially reducing it to object detection. This approach allows for a much more efficient use of the paleographer’s time and produces results that can compete and even outperform pixel-level segmentation in some use cases. Further experiments shed light on how to design a class ontology in order to make the best use of annotators’ time and effort. Exploiting the presence of calibration cards in the image, we further annotate the data with the physical length in pixels and train regression neural networks to predict it from image patches.

This is a preview of subscription content, log in via an institution to check access.

Access this chapter

Chapter
USD 29.95
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
eBook
USD 59.99
Price excludes VAT (USA)
  • Available as EPUB and PDF
  • Read on any device
  • Instant download
  • Own it forever
Softcover Book
USD 74.99
Price excludes VAT (USA)
  • Compact, lightweight edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

Notes

  1. 1.

    Software available under an open-source licence at https://github.com/anguelos/frat and in pypi https://pypi.org/project/frat/.

  2. 2.

    The code has been forked from the original YOLOv5 repository, the specific scripts used for the experiments are in the bin folder https://github.com/anguelos/yolov5/tree/master/bin.

  3. 3.

    The code used to run the resolution regression experiments, including links to the datasets, is available in a github repository https://github.com/anguelos/resolution_regressor.

References

  1. Boroş, E., et al.: A comparison of sequential and combined approaches for named entity recognition in a corpus of handwritten medieval charters. In: 2020 17th International conference on frontiers in handwriting recognition (ICFHR), pp. 79–84. IEEE (2020)

    Google Scholar 

  2. Deng, J., Dong, W., Socher, R., Li, L.J., Li, K., Fei-Fei, L.: Imagenet: a large-scale hierarchical image database. In: 2009 IEEE Conference on Computer Vision and Pattern Recognition, pp. 248–255. IEEE (2009)

    Google Scholar 

  3. Filatkina, N.: Historische formelhafte sprache. In: Historische formelhafte Sprache. de Gruyter (2018)

    Google Scholar 

  4. He, K., Zhang, X., Ren, S., Sun, J.: Deep residual learning for image recognition. In: Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition, pp. 770–778 (2016)

    Google Scholar 

  5. Jaderberg, M., Simonyan, K., Zisserman, A., Kavukcuoglu, K.: Spatial transformer networks. In: Cortes, C., Lawrence, N., Lee, D., Sugiyama, M., Garnett, R. (eds.) Advances in Neural Information Processing Systems, vol. 28. Curran Associates, Inc. (2015)

    Google Scholar 

  6. Jocher, G.: YOLOv5 by Ultralytics (2020). https://doi.org/10.5281/zenodo.3908559, https://github.com/ultralytics/yolov5

  7. Jocher, G., et al.: ultralytics/yolov5: v3.1 - Bug Fixes and Performance Improvements (2020). https://doi.org/10.5281/zenodo.4154370

  8. Leipert, M., Vogeler, G., Seuret, M., Maier, A., Christlein, V.: The notary in the haystack – countering class imbalance in document processing with CNNs. In: Bai, X., Karatzas, D., Lopresti, D. (eds.) DAS 2020. LNCS, vol. 12116, pp. 246–261. Springer, Cham (2020). https://doi.org/10.1007/978-3-030-57058-3_18

    Chapter  Google Scholar 

  9. Lin, T.-Y., et al.: Microsoft COCO: common objects in context. In: Fleet, D., Pajdla, T., Schiele, B., Tuytelaars, T. (eds.) ECCV 2014. LNCS, vol. 8693, pp. 740–755. Springer, Cham (2014). https://doi.org/10.1007/978-3-319-10602-1_48

    Chapter  Google Scholar 

  10. Neudecker, C., et al.: Ocr-d: an end-to-end open source ocr framework for historical printed documents. In: Proceedings of the 3rd International Conference on Digital Access to Textual Cultural Heritage, pp. 53–58 (2019)

    Google Scholar 

  11. Nicolaou, A., Christlein, V., Riba, E., Shi, J., Vogeler, G., Seuret, M.: Tormentor: deterministic dynamic-path, data augmentations with fractals. In: Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition, pp. 2707–2711 (2022)

    Google Scholar 

  12. Pletschacher, S., Antonacopoulos, A.: The page (page analysis and ground-truth elements) format framework. In: 2010 20th International Conference on Pattern Recognition, pp. 257–260. IEEE (2010)

    Google Scholar 

  13. Seuret, M., et al.: Combining ocr models for reading early modern printed books (2023)

    Google Scholar 

Download references

Acknowledgements

The work presented in this paper has been supported by ERC Advanced Grant project (101019327) “From Digital to Distant Diplomatics" and by the DFG grant No. CH 2080/2-1 “Font Group Recognition for Improved OCR".

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Anguelos Nicolaou .

Editor information

Editors and Affiliations

Rights and permissions

Reprints and permissions

Copyright information

© 2023 The Author(s), under exclusive license to Springer Nature Switzerland AG

About this paper

Check for updates. Verify currency and authenticity via CrossMark

Cite this paper

Nicolaou, A., Luger, D., Decker, F., Renet, N., Christlein, V., Vogeler, G. (2023). Efficient Annotation of Medieval Charters. In: Coustaty, M., Fornés, A. (eds) Document Analysis and Recognition – ICDAR 2023 Workshops. ICDAR 2023. Lecture Notes in Computer Science, vol 14193. Springer, Cham. https://doi.org/10.1007/978-3-031-41498-5_20

Download citation

  • DOI: https://doi.org/10.1007/978-3-031-41498-5_20

  • Published:

  • Publisher Name: Springer, Cham

  • Print ISBN: 978-3-031-41497-8

  • Online ISBN: 978-3-031-41498-5

  • eBook Packages: Computer ScienceComputer Science (R0)

Publish with us

Policies and ethics