The Newspaper and Periodical Corpus of the National Library of Finland, Kielipankki Version

Suomeksi

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Currently available versions of this resource

Upcoming versions of this resource

These resource versions are not yet available in the Language Bank of Finland.

Resource information

The corpus contains newspapers and periodicals of the digital collections of the National Library of Finland from the years 1771–2021. The corpus has been split into subcorpora by the year of publication, but consecutive years with relatively little material have been combined to larger subcorpora.

Please note that Korp searches may be slow because of the large size of the corpus, so you should at least at first try searching from a small subset of the corpus. The size of individual years of the corpus also varies significantly.

The language of the sentences of the corpus has been identified with the HeLI-OTS language identifier.

The links in the corpus to page images and PDF files lead to the digital collections of the National Library of Finland. For most publications since 1940, page images and PDF files may only be used for research purposes, and accessing them requires logging in to the service of the National Library and submitting an application.

Further details of each version of the resource are maintained in the metadata record, findable via the persistent identifier (see the link at the resource title).

Contents

• Listing of the newspapers and magazines included in the Finnish sub-corpus, version 1
• Listing of the newspapers and magazines included in the Finnish sub-corpus, version 2
• Listing of the newspapers and magazines included in the Swedish sub-corpus, version 1
• Listing of the newspapers and magazines included in the Swedish sub-corpus, version 2

N-grams (separate resource)

• Based on the KLK data, word-level collections of uni-, bi- and trigrams have been created and are available for download. These are provided as a separate group of resources, The N-grams of the Newspaper and Periodical Corpus of the National Library of Finland.

Important notes

• Previously, the Finnish acronym for the corpora The Newspaper and Periodical OCR Corpus of the National Library of Finland used to be ”Digilib”. Currently, the acronym ”klk” and the short names klk-fi-1874-dl and klk-fi-1920-dl are recommended instead.

License and access

• Some versions of this resource are available publicly (PUB), whereas others may require you to log in as an academic user (ACA) or to apply for individual access rights (RES). Click on the license image to see the resource-specific license text.

Examples of use (Korp versions)

 

 

 

OCR quality

The corpora consist mainly of digitized versions of texts originally printed on paper. These physical papers have been scanned, and optical character recognition (OCR) was performed on the resulting images. The digitized material spans a long period and contains different kinds of texts, writing styles and fonts. Scanning some parts of the material is more complex than scanning other parts, and the physical condition of the original texts also varies. The OCR techniques used have also varied, and there is the possibility that some of the texts have gone through manual post-correction. This results in some parts of the corpora being of terrible quality while others are of good quality. We have collected a list of publications related to OCR quality and collection processing:

• Kettunen, K., & Pääkkönen, T. (2016, May). Measuring lexical quality of a historical finnish newspaper collection―Analysis of Garbled OCR data with basic language technology tools and means. In Proceedings of the Tenth International Conference on Language Resources and Evaluation (LREC’16) (pp. 956-961).

• Koistinen, M., Kettunen, K., & Kervinen, J. (2017). How to improve optical character recognition of historical Finnish newspapers using open source Tesseract OCR engine. Proc. of LTC, 279-283.

• Kettunen, K., Kervinen, J., & Koistinen, M. (2018, April). Creating and Using Ground Truth OCR Sample Data for Finnish Historical Newspapers and Journals. In DHN (pp. 162-169).

• Kettunen, K., Koistinen, M., & Ruokolainen, T. (2018, April). Research and Development Efforts on the Digitized Historical Newspaper and Journal Collection of The National Library of Finland. In DHN (pp. 474-479).

• Kettunen, K., & Koistinen, M. (2019, March). Open Source Tesseract in Re-OCR of Finnish Fraktur from 19th and Early 20th Century Newspapers and Journals-Collected Notes on Quality Improvement. In DHN (pp. 270-282).

• Drobac, S. (2020). OCR and post-correction of historical newspapers and journals. University of Helsinki.

• Hamdi, A., Jean-Caurant, A., Sidère, N., Coustaty, M., & Doucet, A. (2020). Assessing and minimizing the impact of OCR quality on named entity recognition. In Digital Libraries for Open Knowledge: 24th International Conference on Theory and Practice of Digital Libraries, TPDL 2020, Lyon, France, August 25–27, 2020, Proceedings 24 (pp. 87-101). Springer International Publishing.

• Kettunen, K., Koistinen, M., & Kervinen, J. (2020). Ground truth OCR sample data of Finnish historical newspapers and journals in data improvement validation of a re-OCRing process. LIBER Quarterly: The Journal of the Association of European Research Libraries, 30(1), 1-20.

• Jauhiainen, T., Piitulainen, J., Axelson, E., & Lindén, K. (2022, October). Language identification as part of the text corpus creation pipeline at the language bank of finland. In Digital Humanities in the Nordic and Baltic Countries Conference (pp. 251-259). CEUR.

• Kettunen, K., Keskustalo, H., Kumpulainen, S., Pääkkönen, T., & Rautiainen, J. (2022). OCR quality affects perceived usefulness of historical newspaper clippings–a user study. arXiv preprint arXiv:2203.03557.

• Rautiainen, J. (2022). Digitized Finnish Newspapers in Digital Humanities Research Projects: Challenges and Solutions from the Library Perspective.

 

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This page has a Persistent Identifier: http://urn.fi/urn:nbn:fi:lb-2021092404

 

Last modified on 2026-09-28