Survey of Mathematical Expression Image Processing

Mathematical expressions exist in all kinds of documents. Thus, the automatic location, recognition, analysis and understanding of mathematical expressions are important to document image processing. However, because of the many differences between mathematical expressions and normal texts, expression processing is far more difficult than ordinary text recognition. This paper reviews the history of mathematical expression image processing, presents the modules of expression processing, surveys the primary processing methods of exPression extraction, expression recognition, expression analysis and performance evaluation, and gives the perspective of future research directions.