1. A method for relating objects, implemented on a computing device, the method comprising: forming a directed graph of connected objects from a feature-object database, wherein the feature-object database comprises, a plurality of feature-object database keys, each feature-object database key comprising a feature value calculated from a feature extracted from an object; and at least one feature-object database value corresponding to each feature-object database key, the at least one feature-object database value comprising an object identifier identifying an object having the feature corresponding to the corresponding feature-object database key; and wherein the forming a directed graph comprises, for each feature object database key having a plurality corresponding feature-object database values, selecting the corresponding feature-object database values and adding the corresponding objects identifiers as connected nodes in the directed graph of connected objects; and identifying clusters of connected objects from the directed graph of connected objects.