1 2There are more than one database managed by digiKam : 3 4- Core database which host all albums, items, searches data. 5- Thumbnails database to host image thumbs with wavelets compression images. 6- Similarity database to host image finger-prints with computed Haar algorithms. 7- Face database to host face areas on images and face histograms used by faces recognition. 8 For technical reasons, code is located in libs/facesengine/facedb. 9 10collection/ Collections management interface. 11coredb/ Core database implementation based on Database Engine. 12dbjobs/ Database jobs manager. 13engine/ Low Level database engine common to all database interface. 14haar/ Haar fingerprint algorithms used by Fuzzy Search tool. 15history/ Item history algorithms. 16imgqsort/ Image Quality algorithms. 17item/ Item management interfaces. 18server/ Internal database server. 19similaritydb/ Similarity database implementation based on Database Engine 20tags/ Tags management and Face tags interface. 21thumbsdb/ Thumbnails database implementation based on Database Engine. 22utils/ High level implementation based on Core database interface plus widgets and dialogs. 23