A Unified Multilingual Handwriting Recognition System using multigrams sub-lexical units

We address the design of a unified multilingual system for handwriting recognition. Most of multi- lingual systems rests on specialized models that are trained on a single language and one of them is selected at test time. While some recognition systems are based on a unified optical model, dealing with a unified language model remains a major issue, as traditional language models are generally trained on corpora composed of large word lexicons per language. Here, we bring a solution by con- sidering language models based on sub-lexical units, called multigrams. Dealing with multigrams strongly reduces the lexicon size and thus decreases the language model complexity. This makes pos- sible the design of an end-to-end unified multilingual recognition system where both a single optical model and a single language model are trained on all the languages. We discuss the impact of the language unification on each model and show that our system reaches state-of-the-art methods perfor- mance with a strong reduction of the complexity.Comment: preprin

Hybrid model of post-processing techniques for Arabic optical character recognition

Optical character recognition (OCR) is used to extract text contained in an image. One of the stages in OCR is the post-processing and it corrects the errors of OCR output text. The OCR multiple outputs approach consists of three processes: differentiation, alignment, and voting. Existing differentiation techniques suffer from the loss of important features as it uses N-versions of input images. On the other hand, alignment techniques in the literatures are based on approximation while the voting process is not context-aware. These drawbacks lead to a high error rate in OCR. This research proposed three improved techniques of differentiation, alignment, and voting to overcome the identified drawbacks. These techniques were later combined into a hybrid model that can recognize the optical characters in the Arabic language. Each of the proposed technique was separately evaluated against three other relevant existing techniques. The performance measurements used in this study were Word Error Rate (WER), Character Error Rate (CER), and Non-word Error Rate (NWER). Experimental results showed a relative decrease in error rate on all measurements for the evaluated techniques. Similarly, the hybrid model also obtained lower WER, CER, and NWER by 30.35%, 52.42%, and 47.86% respectively when compared to the three relevant existing models. This study contributes to the OCR domain as the proposed hybrid model of post-processing techniques could facilitate the automatic recognition of Arabic text. Hence, it will lead to a better information retrieval

Note Taking in the Digital Age – Towards a Ubiquitous Pen Interface

The cultural technique of writing helped humans to express, communicate, think, and memorize throughout history. With the advent of human-computer-interfaces, pens as command input for digital systems became popular. While current applications allow carrying out complex tasks with digital pens, they lack the ubiquity and directness of pen and paper. This dissertation models the note taking process in the context of scholarly work, motivated by an understanding of note taking that surpasses mere storage of knowledge. The results, together with qualitative empirical findings about contemporary scholarly workflows that alternate between the analog and the digital world, inspire a novel pen interface concept. This concept proposes the use of an ordinary pen and unmodified writing surfaces for interacting with digital systems. A technological investigation into how a camera-based system can connect physical ink strokes with digital handwriting processing delivers artificial neural network-based building blocks towards that goal. Using these components, the technological feasibility of in-air pen gestures for command input is explored. A proof-of-concept implementation of a prototype system reaches real-time performance and demonstrates distributed computing strategies for realizing the interface concept in an end-user setting