digiKam - Advanced Digital Photo Management
digiKam is an advanced digital photo management application for KDE, which makes importing and organizing digital photos a snap. The photos can be organized in albums which can be sorted chronologically, by directory layout or by custom collections. It provides support to add tag, comment to your images.
The digiKam Image Editor has its own plugin subsystem with some common tools e.g. red eye correction or Gamma correction. Additional plugins are provided with the main application to process advanced corrections on image like color management, noise reduction, or special effects. digiKam Image Editor supports all camera RAW file formats, 16 bits color depth, Exif/Makernote/IPTC/GPS/XMP metadata, Color management, tagging/rating/comments pictures, etc.