A Unified Framework for Recognizing Handwritten Chemical Expressions

Chemical expressions have more variant structures in 2-D space than that in math equations. In this paper we propose a unified framework for recognizing handwritten chemical expressions including both inorganic and organic expressions. A set of novel statistical algorithms is presented in two key components of this framework: symbol grouping and structure analysis. Non-symbol modeling and intergroup modeling are proposed to achieve better grouping result, and bond modeling is proposed to group the special bond symbols in the unified framework. A graph-based representation (CESG) is defined for representing generic chemical expressions, and the structure analysis problem is formulated as a search problem for CESG over a weighted direction graph. Experiments on a database of more than 35,000 expressions were conducted and results are presented.

• Type: Journal
• Year: 2009
• Where: ICDAR
• Authors: Ming Chang, Shi Han, Dongmei Zhang
• Keywords: Chemical Expressions, Document Analysis, ICDAR 2009, Structure Analysis, Unified Framework