The KDE application KPhotoAlbum (http://www.kphotoalbum.org) has an export feature where it allows the user to export images and annotation in a file with mime type application/vnd.kde.kphotoalbum-import, and ending in .kim. The file is a zip archive, with the following files in it: index.xml - file in the format that kphotoalbum uses for it storing Thumbnails/* jpg thumbnails for each file in the archive. Kind Regards Jesper.
If only one application handles that type of data, it would be best for the application to ship the mime-type itself.
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