About_plugins

Xena uses a series of plugins to normalise input files to preservation file formats. By using all the available plugins, Xena can normalise a wide range of file formats. However, for some file formats (such as video), there is no corresponding Xena plugin.

A plugin consists of one or more components, with each component having a specific role in the normalisation process. The normaliser is one of these components. The normaliser is responsible for taking the input file and transforming it into a Xena XML file.

When you start Xena, it loads all the plugins available under the Xena/plugins directory. If you attempt to normalise a certain file format and the corresponding plugin is either not in the plugins directory or does not exist (for example video), Xena will only binary normalise the input file. In such cases, the Normaliser column of the Normalisation Results is either blank or displays one of the following:

• Unsupported Type Normaliser
• Binary.

Xena will binary normalise any files that are already in a preservation file format (such as PNG). This is because the files are already in the desired format and do not need to be converted.

External programs

Some of the Xena plugins call on external programs to normalise certain file types. For Xena to work properly with all supported file formats, you will need to install the following external programs:

• FLAC (<http://flac.sourceforge.net>) is a free and open source software tool and file format for lossless audio data compression - see [Setting_up_the_audio_plugin]
• Readpst is part of the free and open source libpst software suite (<http://www.five-ten-sg.com/libpst/>), which converts PST files to MBOX format - see [Setting_up_the_email_plugin]
• Convert is part of the free and open source ImageMagick software suite (<http://www.imagemagick.org>) for displaying, converting and editing raster image files - see [Setting_up_the_image_plugins]
• Tesseract (<http://code.google.com/p/tesseract-ocr/>) is a free and open source Optical Character Recognition (OCR) engine used to create text versions of certain files - see [Setting_up_the_image_plugins]
• Libreoffice (<http://www.libreoffice.org/>) is a free and open source office suite which supports numerous file formats - see [Setting_up_the_office_plugin]

Note: Depending on your operating system, some of the above external programs may be included in the Xena distribution.

For more information about plugins and their components, see How to create a Xena plugin - [1_-_Introduction].