Real‐time recognition of handwritten math formulas

Abstract

AbstractThis paper proposes a method of realizing a handwritten mathematical formula input system that works in real time. In the handwritten character input, the data is input generally for each stroke (segment). The proposed method is based on this property. The mathematical formula is recognized on the basis of the result of recognition of the individual input strokes and their positional relations. Then the LaTeX source code is generated. In this paper, mathematical symbols are considered as characters, and are integrated into character recognition. More precisely, each time a stroke is input, it is recognized as a single‐stroke character. The crossing with the already input characters is examined, and the character is extracted so that the likelihood of forming character is maximized. Based on the positional relations among the extracted characters, the structure of the mathematical formula, such as superscripts/subscripts and fractions, is recognized. The mathematical structures that can be recognized by the proposed method are the structures obtained by combining five different structures, namely, superscript/subscript, root, overline, underline, and fraction. The recognition is not affected by the order of input. The proposed method is applied to various mathematical formulas, and it is seen that the proposed system works adequately as an input environment for real‐time processing. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 87(8): 66–81, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.20086