Foto-Mosaic-Edda Database
A Foto-Mosaic-Edda Database is used by Foto-Mosaic-Edda (called just "Foto-Mosaic" before a rewrite in version 5.3.0 (2009)[2]), a program by Steffen Schirmer[3] that takes a large number of images and arranges and colors them into a "mosaic" of another image, to store the constituent images. It is presumably a collection of thumbnails (of user-choosable size) of these images. It consisted of two files, one starting with ".dat" (which looks to be nothing more than a concatenation of the images) and the other with ".idx" (an index), before v. 5.3.0; afterwards, it is a single file with extension ".fmedb".
Identification
Post-5.3.0 databases start with ASCII FMEDB
. Index files seem to start with the bytes 0D 4D 49 44 58 44 41 54 48 45 41 44 45 52
, which is 0x0D followed by "MIDXDATAHEADER" in ASCII.