All Outputs (21)

Encoding of Digitised Documents (2025)
Thesis

This work presents solutions to the multifaceted problem of document encoding in the context of digitisation processes. It addresses aspects related to structure and layout on page level as well as mechanisms for representing underlying textual infor... Read More about Encoding of Digitised Documents.

NAME – A Rich XML Format for Named Entity and Relation Tagging (2023)
Presentation / Conference Contribution

We present NAME XML, a schema for named entities and relations in documents. The standout features are: option to reference a variety of document formats (such as PAGE XML or plain text), support of entity hierarchies, custom entity types via ontolog... Read More about NAME – A Rich XML Format for Named Entity and Relation Tagging.

A survey of OCR evaluation tools and metrics (2021)
Presentation / Conference Contribution

The millions of pages of historical documents that are digitized in libraries are increasingly used in contexts that have more specific requirements for OCR quality than keyword search. How to comprehensively, efficiently and reliably assess the qual... Read More about A survey of OCR evaluation tools and metrics.

Flexible character accuracy measure for reading-order-independent evaluation (2020)
Journal Article

The extraction of textual information from scanned document pages is a fundamental stage in any digitisation effort and directly determines the success of the overall document analysis and understanding application scenarios. To evaluate and improve... Read More about Flexible character accuracy measure for reading-order-independent evaluation.

A cloud-hosted MapReduce architecture for syntactic parsing (2019)
Presentation / Conference Contribution

Syntactic parsing is a time-consuming task innatural language processing particularlywherea largenumber of text files are beingprocessed. Parsingalgorithms are conventionally designed to operate on a single machine in a sequenti... Read More about A cloud-hosted MapReduce architecture for syntactic parsing.

Efficient and effective OCR engine training (2019)
Journal Article
Clausner, C., Antonacopoulos, A., & Pletschacher, S. (2020). Efficient and effective OCR engine training. International Journal on Document Analysis and Recognition, 23(1), 73-78. https://doi.org/10.1007/s10032-019-00347-8

We present an efficient and effective approach to train OCR engines using the Aletheia document analysis system. All components required for training are seamlessly integrated into Aletheia: training data preparation, the OCR engine’s training proces... Read More about Efficient and effective OCR engine training.

ICDAR2017 Competition on Recognition of Early Indian Printed Documents – REID2017 (2017)
Presentation / Conference Contribution

This paper presents an objective comparative evaluation of page analysis and recognition methods for historical documents with text mainly in Bengali language and script. It describes the competition (modus operandi, dataset and evaluation methodolog... Read More about ICDAR2017 Competition on Recognition of Early Indian Printed Documents – REID2017.

ICDAR2017 Competition on Recognition of Documents with Complex Layouts – RDCL2017 (2017)
Presentation / Conference Contribution

This paper presents an objective comparative evaluation of page segmentation and region classification methods for documents with complex layouts. It describes the competition (modus operandi, dataset and evaluation methodology) held in the context o... Read More about ICDAR2017 Competition on Recognition of Documents with Complex Layouts – RDCL2017.

Creating a complete workflow for digitising historical census documents : considerations and evaluation (2017)
Presentation / Conference Contribution

The 1961 Census of England and Wales was the first UK census to make use of computers. However, only bound volumes and microfilm copies of printouts remain, locking a wealth of information in a form that is practically unusable for research. In this... Read More about Creating a complete workflow for digitising historical census documents : considerations and evaluation.

Unearthing the recent past : digitising and understanding statistical information from census tables (2017)
Presentation / Conference Contribution

Censuses comprise a wealth of information at a large (national) scale that allow governments (who commission them) and the public to have a detailed snapshot of how people live (geographical distribution and characteristics). In addition to underpinn... Read More about Unearthing the recent past : digitising and understanding statistical information from census tables.

Effective geometric restoration of distorted historical documents for large-scale digitization (2017)
Journal Article
Yang, P., Antonacopoulos, A., Clausner, C., Pletschacher, S., & Qi, J. (2017). Effective geometric restoration of distorted historical documents for large-scale digitization. IET Image Processing, 11(10), 841-853. https://doi.org/10.1049/iet-ipr.2016.0973

Due to storage conditions and material’s non-planar shape, geometric distortion of the 2-D content is widely present in scanned document images. Effective geometric restoration of these distorted document images considerably increases character recog... Read More about Effective geometric restoration of distorted historical documents for large-scale digitization.

Quality prediction system for large-scale digitisation workflows (2016)
Presentation / Conference Contribution

The feasibility of large-scale OCR projects can so far only be assessed by running pilot studies on subsets of the target document collections and measuring the success of different workflows based on precise ground truth, which can be very costly to... Read More about Quality prediction system for large-scale digitisation workflows.

Europeana newspapers OCR workflow evaluation (2015)
Presentation / Conference Contribution

This paper summarises the final performance evaluation results of the OCR workflow which was employed for large-scale production in the Europeana Newspapers project. It gives a detailed overview of how the involved software performed... Read More about Europeana newspapers OCR workflow evaluation.

ICDAR2015 competition on recognition of documents with complex layouts - RDCL2015 (2015)
Book Chapter
Antonacopoulos, A., Clausner, C., Papadopoulos, C., & Pletschacher, S. (2015). ICDAR2015 competition on recognition of documents with complex layouts - RDCL2015. In 2015 13th International Conference on Document Analysis and Recognition (ICDAR) (1151-1155). IEEE. https://doi.org/10.1109/ICDAR.2015.7333941

This paper presents an objective comparative evaluation of page segmentation and region classification methods for documents with complex layouts. It describes the competition (modus operandi, dataset and evaluation methodology) held in the context o... Read More about ICDAR2015 competition on recognition of documents with complex layouts - RDCL2015.

Document representation refinement for precise region description (2014)
Presentation / Conference Contribution

Precise description of layout entities (content regions on a page) is crucial for all but the most trivial document analysis and recognition applications. The output of layout analysis methods and state-of-the-art OCR systems varies significantly, fr... Read More about Document representation refinement for precise region description.

The IMPACT dataset of historical document images (2013)
Presentation / Conference Contribution

Representative and comprehensive datasets are a prerequisite for any research activity, from studying specific types of problems through training of algorithms to evaluating results of actual implementations. This paper describes an invaluable resour... Read More about The IMPACT dataset of historical document images.

The significance of reading order in document recognition and its evaluation (2013)
Presentation / Conference Contribution

Reading order detection and representation is an important task in many digitisation scenarios involving the preservation of the logical structure of a document. The corresponding need for the evaluation of reading order results generated by layout a... Read More about The significance of reading order in document recognition and its evaluation.

Aletheia - An advanced document layout and text ground-truthing system for production environments (2011)
Presentation / Conference Contribution

Large-scale digitisation has led to a number of new possibilities with regard to adaptive and learning based methods in the field of Document Image Analysis and OCR. For ground truth production of large corpora, however, there is still a gap in terms... Read More about Aletheia - An advanced document layout and text ground-truthing system for production environments.

The PAGE (Page Analysis and Ground-Truth Elements) format framework (2010)
Presentation / Conference Contribution

There is a plethora of established and proposed document representation formats but none that can adequately support individual stages within an entire sequence of document image analysis methods (from document image enhancement to layout analysis to... Read More about The PAGE (Page Analysis and Ground-Truth Elements) format framework.

A new framework for recognition of heavily degraded characters in historical typewritten documents based on semi-supervised clustering (2009)
Presentation / Conference Contribution

This paper presents a new semi-supervised clustering
framework to the recognition of heavily degraded characters
in historical typewritten documents, where off-theshelf
OCR typically fails. The constraints are generated
using typographical (colle... Read More about A new framework for recognition of heavily degraded characters in historical typewritten documents based on semi-supervised clustering.