An IFilter is a
plugin that allows Microsoft's search engines to index various
file format
A file format is a standard way that information is encoded for storage in a computer file. It specifies how bits are used to encode information in a digital storage medium. File formats may be either proprietary or free.
Some file format ...
s (as documents, email attachments, database records, audio metadata etc.) so that they become searchable. Without an appropriate IFilter, contents of a file cannot be parsed and indexed by the search engine.
They can be obtained as standalone packages or bundled with certain software such as
Adobe Reader,
[Adobe provides only the 32-bit IFilter bundled with its Reader software. To install the 64-bit version, there is a standalone package a]
Acrobat for Windows Downloads Page
LibreOffice
LibreOffice () is a free and open-source office productivity software suite, a project of The Document Foundation (TDF). It was forked in 2010 from OpenOffice.org, an open-sourced version of the earlier StarOffice. The LibreOffice suite co ...
,
Microsoft Office
Microsoft Office, or simply Office, is the former name of a family of client software, server software, and services developed by Microsoft. It was first announced by Bill Gates on August 1, 1988, at COMDEX in Las Vegas. Initially a marketin ...
[
Microsoft provides its Office IFilters bundled and available as standalone packages a]
Microsoft Office 2010 Filter Packs
an
2007 Office System Converter: Microsoft Filter Pack
and
OpenOffice OpenOffice or open office may refer to:
Computing Software
* OpenOffice.org (OOo), a discontinued open-source office software suite, originally based on StarOffice
* Apache OpenOffice (AOO), a derivative of OOo by the Apache Software Foundation, w ...
.
It also refers to the software interface needed to implement such plugins.
How it works Windows Search Service documentation on MSDN
/ref>
An IFilter acts as a plug-in for extracting full-text and metadata for search engines. A search engine usually works in two steps:
# The search engine goes through a designated place, e.g. a file folder or a database, and indexes all documents or newly modified documents, including the various types documents, in the background and creates internal data to store indexing result.
# A user specifies some keywords they would like to search for, and the search engine answers the query immediately by looking up the indexing result and responding to the user with all the documents that contains the keywords.
During Step 1, the search engine itself doesn't understand format of a document. Therefore, it looks on
Windows
Windows is a group of several proprietary graphical operating system families developed and marketed by Microsoft. Each family caters to a certain sector of the computing industry. For example, Windows NT for consumers, Windows Server for se ...
registry for an appropriate IFilter to extract the data from the document format, filtering out embedded formatting and any other non-textual data.
Search engines
Windows Indexing Service
Indexing Service (originally called Index Server) was a Windows service that maintained an index of most of the files on a computer to improve searching performance on PCs and corporate computer networks. It updated indexes without user interve ...
and the newer
Windows Search
Windows Search (also known as Instant Search) is a content index desktop search platform by Microsoft introduced in Windows Vista as a replacement for both the previous Indexing Service of Windows 2000 and the optional MSN Desktop Search for Win ...
,
Windows Desktop Search
Windows Search (also known as Instant Search) is a content index desktop search platform by Microsoft introduced in Windows Vista as a replacement for both the previous Indexing Service of Windows 2000 and the optional MSN Desktop Search for Wind ...
, MSN Desktop Search, Internet Information Server, SharePoint Portal Server, Windows SharePoint Services (WSS), Site Server, Exchange Server, SQL Server and all other products based on Microsoft Search technology support indexing technology. Also, IFilters are used by
SQL Server as a component of the
SQL Server Full Text Search service.
See also
*
IUnknown In computer programming, the IUnknown interface is the fundamental interface in the Component Object Model (COM). The COM specification mandates that COM objects must implement this interface. Furthermore, every other COM interface must be derived ...
Notes
References
External links
Filter Central— Microsoft Search Filters Discussion Board;
IFilter.org— Downloads and documentation;
MSG IFilter— IFilter for
Outlook
Outlook or The Outlook may refer to:
Computing
* Microsoft Outlook, an e-mail and personal information management software product from Microsoft
* Outlook.com, a web mail service from Microsoft
* Outlook on the web, a suite of web applications ...
Message Files (.MSG) for
Windows Desktop Search
Windows Search (also known as Instant Search) is a content index desktop search platform by Microsoft introduced in Windows Vista as a replacement for both the previous Indexing Service of Windows 2000 and the optional MSN Desktop Search for Wind ...
;
IFilterShop— Some IFilters available as free for non-commercial users.
PDF iFilter Win x64 11.0.01— Adobe PDF iFilter for 64bit Windows systems. Reader and Acrobat include iFilter for 32bit Windows systems.
PDF IFilter— Foxit PDF IFilter. Works on Windows OS.
PDFlib TET PDF IFilter— PDF IFilter from PDFlib. Works on Windows OS.
— iFilter Downloads.
— Windows Search connector for IBM Lotus Notes.
Various IFilters.
{{Windows Components
Windows components
Microsoft application programming interfaces
Microsoft software