Methods, apparatus and programs for generating and utilizing content signatures

摘要

The present invention relates to deriving and/or utilizing content signatures. A content signature includes a representation of a content item, which is derived or calculated from the content item itself. One claim recites a method comprising: obtaining a content item; transforming the content item to obtain transform domain coefficients; applying Viterbi decoding to a set of the transform domain coefficients; and using a result of the Viterbi decoding as a content signature representing features or characteristics of the content item itself. Other claims and combinations are provided too.