A Dataset of Wolof Ajami Manuscripts for HTR and OCR
Oreen Yousuf, Elhadji Djibril Diagne, Christian Høgel, Beata Megyesi, Joakim Nivre
Abstract
We present the first ever dataset of manually segmented and transcribed Ajami manuscripts written in Wolof. The term Ajami refers to modified Arabic-script orthographies used to transcribe African languages. Handwritten text recognition (HTR) and optical character recognition (OCR) models for Arabic-script languages perform poorly on African languages written in Ajami orthographies because these languages are not represented in the pre-training data of the models. This leads to recognition models being unable to extract unique Arabic-script letters and ubiquitous diacritics used in African languages, and struggling to adapt to various calligraphy styles used across Africa. We release the following as an open-source dataset: an ALTO formatting of high-quality images of handwritten and printed, 20th–century Wolof manuscripts; manual segmentation (region and line); and manual transcriptions. We extend our contribution by evaluating several Arabic-script recognition models intended for historical manuscripts and find they produce character error rates (CER) of 61–81%. Transcriptions produced by the evaluated recognition models, as well as a keyboard to transcribe Wolof Ajami manuscripts, are released as well. The digitally transcribed text in the dataset can also be utilized for various natural language processing (NLP) and historical linguistic tasks.- Anthology ID:
- 2026.lrec-1.253
- Volume:
- Proceedings of the Fifteenth Language Resources and Evaluation Conference
- Month:
- May
- Year:
- 2026
- Address:
- Palma de Mallorca, Spain
- Editors:
- Stelios Piperidis, Núria Bel, Henk van den Heuvel, Nancy Ide, Simon Krek, Antonio Toral
- Venue:
- LREC
- SIG:
- Publisher:
- ELRA Language Resource Association
- Note:
- Pages:
- 3234–3239
- Language:
- External URL:
- https://lrec.elra.info/lrec2026-main-253
- DOI:
- 10.63317/4pz98ojeeqpw
- Cite (ACL):
- Oreen Yousuf, Elhadji Djibril Diagne, Christian Høgel, Beata Megyesi, and Joakim Nivre. 2026. A Dataset of Wolof Ajami Manuscripts for HTR and OCR. In Proceedings of the Fifteenth Language Resources and Evaluation Conference, pages 3234–3239, Palma de Mallorca, Spain. ELRA Language Resource Association.
- Cite (Informal):
- A Dataset of Wolof Ajami Manuscripts for HTR and OCR (Yousuf et al., LREC 2026)