Abstract: Systems and methods for receiving and indexing native digital data and generating signature vectors for subsequent storage and searching for such native digital data in a database of digital data are disclosed. Native digital data may be transformed into associated transform data sets. Such transformation may comprise entropy-like transforms and/or spatial frequency transforms. The native and associated transform data sets may then be partitioned in to spectral components and those spectral components may have statistical moments applied to them to create a signature vector. Other systems and methods for processing non-image digital data are disclosed. Non-image digital data may be transformed into an amplitude vs time data set and a spectrogram may then be applied to such data sets. Such transformed data sets may then be processed as described.