Text line segmentation from struck-out handwritten document images (2022)
Journal Article
Shivakumara, P., Jain, T., Pal, U., Surana, N., Antonacopoulos, A., & Lu, T. (2022). Text line segmentation from struck-out handwritten document images. Expert systems with applications, 210, 118266. https://doi.org/10.1016/j.eswa.2022.118266

In the case of freestyle everyday handwritten documents, writing, erasing, striking out, and overwriting are common behaviors of the writers. This not cleanly-written text poses significant challenges for text line segmentation. Accurate text line se... Read More about Text line segmentation from struck-out handwritten document images.

A new deep wavefront based model for text localization in 3D video (2021)
Journal Article
Nandanwar, L., Shivakumara, P., Ramachandra, R., Lu, T., Pal, U., Antonacopoulos, A., & Lu, Y. (2021). A new deep wavefront based model for text localization in 3D video. IEEE Transactions on Circuits and Systems for Video Technology, 32(6), 3375-3389. https://doi.org/10.1109/TCSVT.2021.3110990

With the evolution of electronic devices, such as 3D cameras, addressing the challenges of text localization in 3D video (e.g., for indexing) is increasingly drawing the attention of the multimedia and video processing community. Existing methods foc... Read More about A new deep wavefront based model for text localization in 3D video.

Flexible character accuracy measure for reading-order-independent evaluation (2020)
Journal Article
Clausner, C., Pletschacher, S., & Antonacopoulos, A. (2020). Flexible character accuracy measure for reading-order-independent evaluation. Pattern Recognition Letters, 131, 390-397. https://doi.org/10.1016/j.patrec.2020.02.003

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.

Ontology and framework for semantic labelling of document data and software methods (2018)
Conference Proceeding
Clausner, C., & Antonacopoulos, A. (2018). Ontology and framework for semantic labelling of document data and software methods. . https://doi.org/10.1109/DAS.2018.46

We present a metadata labelling framework for datasets, software tools, and workflows. An ontology for document image analysis was developed with deep support for historical data. An accompanying open source software framework was implemented to enab... Read More about Ontology and framework for semantic labelling of document data and software methods.

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.

Document representation refinement for precise region description (2014)
Conference Proceeding
Clausner, C., Pletschacher, S., & Antonacopoulos, A. (2014). Document representation refinement for precise region description. In A. Antonacopoulos, & K. Schulz (Eds.), DATeCH '14: Proceedings of the First International Conference on Digital Access to Textual Cultural Heritage. https://doi.org/10.1145/2595188.2595198

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 significance of reading order in document recognition and its evaluation (2013)
Conference Proceeding
Clausner, C., Pletschacher, S., & Antonacopoulos, A. (2013). The significance of reading order in document recognition and its evaluation. In Proceedings of the 2013 12th International Conference on Document Analysis and Recognition. https://doi.org/10.1109/ICDAR.2013.141

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)
Conference Proceeding
Clausner, C., Pletschacher, S., & Antonacopoulos, A. (2011). Aletheia - An advanced document layout and text ground-truthing system for production environments. In 2011 International Conference on Document Analysis and Recognition ICDAR 2011. https://doi.org/10.1109/ICDAR.2011.19

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)
Conference Proceeding
Pletschacher, S., & Antonacopoulos, A. (2010). The PAGE (Page Analysis and Ground-Truth Elements) format framework. In 2010 20th International Conference on Pattern Recognition. https://doi.org/10.1109/ICPR.2010.72

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.

Word-Based adaptive OCR for historical books (2009)
Conference Proceeding
Kluzner, V., Tzadok, A., Shimony, Y., Walach, E., & Antonacopoulos, A. (2009). Word-Based adaptive OCR for historical books. In 2009 10th International Conference on Document Analysis and Recognition. https://doi.org/10.1109/ICDAR.2009.133

The aim of this work is to propose a new approach to the recognition of historical texts by providing an adaptive mechanism that automatically tunes itself to a specific book. The system is based on clustering together all the similar words in a book... Read More about Word-Based adaptive OCR for historical books.

Colour text segmentation in web images based on human perception (2007)
Journal Article
Antonacopoulos, A., & Karatzas, D. (2007). Colour text segmentation in web images based on human perception. Image and Vision Computing, 25(5), 564-577. https://doi.org/10.1016/j.imavis.2006.05.003

Flexible text recovery from degraded typewritten historical documents (2006)
Conference Proceeding
Antonacopoulos, A., & Casado Castilla, C. (2006). Flexible text recovery from degraded typewritten historical documents.

Visual representation of text in web documents and its interpretation (2005)
Book Chapter
Karatzas, D., & Antonacopoulos, A. (2005). Visual representation of text in web documents and its interpretation. In G. Malcolm (Ed.), Multidisciplinary approaches to visual representations and interpretations (181-196). Elsevier. https://doi.org/10.1016/S1571-0831%2804%2980041-8

This chapter examines the uses of text and its representation on Web documents in terms of the challenges in its interpretation. Particular attention is paid to the significant problem of non-uniform representation of text. This non-uniformity is mai... Read More about Visual representation of text in web documents and its interpretation.

A robust braille recognition system (2004)
Book Chapter
Antonacopoulos, A., & Bridson, D. (2004). A robust braille recognition system. In A. Dengel, & S. Marinai (Eds.), Document analysis systems VI (533-545). Springer Berlin / Heidelberg. https://doi.org/10.1007/b100557

Braille is the most effective means of written communication between visually-impaired and sighted people. This paper describes a new system that recognizes Braille characters in scanned Braille document pages. Unlike most other approaches, an ine... Read More about A robust braille recognition system.

Two approaches for text segmentation in web images (2003)
Conference Proceeding
Karatzas, D., & Antonacopoulos, A. (2003). Two approaches for text segmentation in web images.

Page segmentation using the description of the background (1998)
Journal Article
Antonacopoulos, A. (1998). Page segmentation using the description of the background. Computer Vision and Image Understanding, 70(3), 350-369. https://doi.org/10.1006/cviu.1998.0691

There is an ever increasing number of publications which do not have the “traditional” layout where printed regions are rectangu- lar. Text paragraphs and areas of graphic type may be of any shape, individually rotated and in any arrangement. Previou... Read More about Page segmentation using the description of the background.

The lifecycle of a digital historical document: structure and content
Conference Proceeding
Antonacopoulos, A., Wiszniewski, B., Krawczyk, H., & Karatzas, D. The lifecycle of a digital historical document: structure and content.

This paper describes the lifecycle of a digital historical document, from template-based structure definition through to content extraction from the scanned pages and its final reconstitution as an electronic document (combining content and semantic... Read More about The lifecycle of a digital historical document: structure and content.