digiKam

digiKam is a free and open-source image organizer and tag editor written in C++ using the KDE Frameworks.

==Features== digiKam runs on most known desktop environments and window managers, as long as the required libraries are installed. It supports all major image file formats, such as JPEG and PNG as well as over 200 raw image formats and can organize collections of photographs in directory-based albums, or dynamic albums by date, timeline, or by tags. Users can also add captions and ratings to their images, search through them and save searches for later use. Using plug-ins, users can export albums to various online services including (among others) 23hq, Facebook, Flickr, Gallery2, Google Earth's KML files, Yandex.Fotki, MediaWiki, Rajce, SmugMug, Piwigo, Simpleviewer, Picasa Web Albums. Plug-ins are also available to enable burning photos to a CD and the creation of web galleries.