Analysis of Text Extraction from PDF Documents of Local Assembly Materials for Constructing Structured Data

Abstract

Local governments publish information about parliamentary activities and financial conditions on their Web sites, many of which are available in PDF document format. PDF documents have a high level of visual expression such as layout. However, it may be difficult to extract text data such as letters and word order from PDF documents because of high flexibility of their internal data representation. Since local governments publish PDF documents with their own format, the methods and difficulty of extracting text data may vary. To be useful as a language resource or Linked Open Data, it is desirable to structure documents on a plain text basis, such as JSON. In this study, we analyze PDF documents of assembly materials published local governments in Fukuoka Prefecture from the viewpoint of the method and difficulty of extracting plain text.