Chemical structure recognition: a rule-based approach

In chemical literature much information is given in the form of diagrams depicting molecules. In order to access this information diagrams have to be recognised and translated into a processable format. We present an approach that models the principal recognition steps for molecule diagrams in a strictly rule based system, providing rules to identify the main components — atoms and bonds — as well as to resolve possible ambiguities. The result of the process is a translation into a graph representation that can be used for further processing. We show the effectiveness of our approach by describing its embedding into a full recognition system and present an experimental evaluation that demonstrates how our current implementation outperforms the leading open source system currently available.