On-Line Handwritten Formula Recognition using Hidden Markov Models and Context Dependent Graph Grammars

Andreas Kosmala (1) , Gerhard Rigoll (1) , Stéphane Lavirotte (2, 3) , Loïc Pottier (2, 3)

1 Universität Duisburg-Essen = University of Duisburg-Essen [Essen]
2 LEMME - Software and mathematics
3 CAFE - Computer algebra and functional equations

This paper presents an approach for the recognition of on-line handwritten mathematical expressions. The Hidden Markov Model (HMM) based system makes use of simultaneous segmentation and recognition capabilities, avoiding a crucial segmentation during pre-processing. With the segmentation and recognition results, obtained from the HMMrecognizer, it is possible to analyze and interpret the spatial two-dimensional arrangement of the symbols. We use a graph grammar approach for the structure recognition, also used in off-line recognition process, resulting in a general tree-structure of the underlying input-expression. The resulting constructed tree can be translated to any desired syntax (for example: Lisp, LaTeX, OpenMath . . . ).

Domaines: Calcul parallèle, distribué et partagé [cs.DC]

Andreas Kosmala, Gerhard Rigoll, Stéphane Lavirotte, Loïc Pottier. On-Line Handwritten Formula Recognition using Hidden Markov Models and Context Dependent Graph Grammars. Fifth International Conference on Document Analysis and Recognition, IEEE Computer Society, Sep 1999, Bangalore, India. ⟨hal-00564645⟩