1. A system for generating a concept database respective of a plurality of multimedia data elements (MMDEs), comprising: an attention processor (AP) for generating a plurality of items from a received MMDE of the plurality of MMDEs and determining which of the generated items are of interest for signature generation; a signature generator (SG) for generating at least one signature responsive to at least one item of interest of the received MMDE of the plurality of MMDEs; a clustering processor (CP) for clustering a plurality of signatures received from the signature generator responsive of the plurality of MMDEs and creating a signature reduced cluster (SRC); a concept generator (CG) for associating metadata with the SRC and forming a concept structure comprised of a plurality of SRCs and their associated metadata; and an index generator (IG) for generating at least one index for mapping the received MMDE to at least one concept structure, wherein the concept database includes concept structures and the generated indices for the plurality of MMDEs.