Greenstone can process a wide array of document types. The table below provides information about document types, their file extensions, the Greenstone plugin(s) that can process these file types, and any additional information about the document type in relation to Greenstone.

Remember that every document in your collection must be processed by a plugin, or it will not be included in your collection. However, if Greenstone does not currently include a plugin that will process your document type, it is possible to create your own.

You may want to have multiple versions of the same document in your collection, or a supplemental file for another document. For example, perhaps you want to have both the Word and PDF version of a document available, but you want them to be connected, since they have the same content. You can do this by associating documents using either the associate_ext or the associate_tail_re options, which are available for all document plugins in Greenstone.

First, you must decide which document will be the primary document. This is the document that will actually be processed by a plugin. In the plugin that will process the primary document (e.g. WordPlugin for Word documents), you can set one of the associated file options:

• associate_ext: This option takes the file extension for the associated documents (e.g. pdf). More than one filename extension can be provided as part of this option, separated by a comma. For example, setting the value of the associate_ext in TextPlugin to avi,png would allow both an AVI video file (say an oral history interview) and a PNG image (say a picture of the interviewee taken at the time of the recording) to bind to a text version of the document (say representing a transcript of the interview). Both AVI and PNG versions of the file can be present at the same time, or alternatively only one of the two file types need be present, or neither, and Greenstone will process the situation accordingly. This option requires that the associated document(s) have the exact same name as the primary document except for the file extension.
• associate_tail_re: This is a more general option, which is able to group files together that share a similar filename root, but might start to differ in characters before the filename extension. For instance, the Word version of the document might be my-article.doc but the PDF version might be my-article-ver13.pdf. Using associate_tail_re, such differences can be surmounted, and the two files still processed automatically as different versions of the same document.