Syntactic Detection and Correction of Misrecognitions in Mathematical OCR

This paper proposes a syntactic method for detection and correction of misrecognized mathematical formulae for a practical mathematical OCR system. Linear monadic context-free tree grammar (LM-CFTG) is employed as a formal framework to define syntactically acceptable mathematical formulae.For the purpose of practical evaluation, a verification system is developed, and the effectiveness of the method is demonstrated by using the ground-truthed mathematical document database InftyCDB-1 and a misrecognition database newly constructed for this study.A satisfactory number of misrecognitions are detected and delivered to the correction process.

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