Plug-In for Search Engines Based on Microsoft's IFilter Index Interface

Foxit PDF IFilter is a robust implementation of Microsoft^®'s IFilter indexing interface. It works with all search and retrieval products supporting the IFilter interface (for example, SharePoint^® and SQL Server^®). Such products use format-specific filter programs (called IFilters) for particular file formats (for example, HTML). Foxit PDF IFilter is such a program, aimed at PDF documents. The user interface for searching the documents may be Windows Explorer, a web browser, database frontend, query script, or a custom application.

Foxit PDF IFilter acts as a plug-in for full-text search engines. A search engine usually works in two steps:

• The search engine goes through a designated place (a file folder or a database), indexes all documents or newly modified documents (including PDF documents), and then stores indexing results in an internal database.
• Users specify keywords they would like to search, the search engine looks up the indexing results in the internal database, and then responding to users with all the documents that contain the specified keywords.

During step 1, the search engine itself doesn't understand the format of a PDF document. Therefore, it looks in the Windows registry for an appropriate PDF IFilter and finds the Foxit PDF IFilter. Since the PDF IFilter understands PDF format, it filters out embedded formatting, extracts text from the documents, and then returns the text back to the search engine.

Foxit PDF IFilter functions in the following search engine environments:

• Microsoft SharePoint Server
• Microsoft Exchange Server
• SQL Server
• Windows Indexing Server
• FAST Search Server

As an alternative to interactive searches, queries can also be submitted programmatically without any user interface on the following Windows operating systems:

• Windows 7
• Windows Vista
• Windows XP
• Windows Server 2008
• Windows Server 2003
• Windows 2000