OpenOffice and LibreOffice can produce documents based on the XML standard language and they create an XML file for contents, one for style and so on. When they must save the whole document, a zip file is created with all the XML and additional files needed by the document, then the zip file gets a different file extension (e.g.: ".ODT" for Writer documents). The worst detail about this beahviour is that they don't use the maximum compression level available in zip format, so ZipGenius can fix this issue.
ZipGenius can extract the contents from such document file and it compress them back using with the Brutal compression level. Thanks to this feature, Libre/OpenOffice documents will be 1-7% smaller than before (that depends by certain conditions such as the number of picture files in the document).
WARNING! Optimization feature can be also applied to encrypted Libre/OpenOffice document but this may lead to data loss, so you must be sure that you are trying to optimize a non-encrypted Libre/OpenOffice document before proceeding.
If you have enabled the support to LibreOffice/Libre/OpenOffice in the Options panel, then you can optimize documents from the context menu: right-click on a document and select "Optimize" in the context menu, in order to optimize that. If you use this method, ZipGenius will be able to optimize more than one document at once (you have only to select multiple Libre/OpenOffice files and right-click on them).
However, you can optimize these documents from ZipGenius because you can open them just as you would do with standard zip files: click "Open" and choose a document. Now, if you have set "NORMAL" layout, ZipGenius will check the document and if it isn't optimized yet, ZG will ask if you want to optimize it. In "EXPERT" layout, on the contrary, you won't prompted for any action and you have to right-click in ZipGenius windows to choose "Optimize document" from ZipGenius popup menu. Anyway you will get additional items in the First Step Assistant menu. One of these allows to optimize all Libre/OpenOffice documents in a single folder.
When you optimize an Libre/OpenOffice document, ZipGenius stores a backup copy with ".BAK" extension, so you may recover the original file; also, ZipGenius add a comment to the document (it's a zip file comment): "ZG". This comment is used to check if the skin file has been already optimized or not. Libre/OpenOffice resets that comment each time it updates a document.
Created with the Personal Edition of HelpNDoc: Create help files for the Qt Help Framework