1. A method for data deduplication comprising: segmenting an original data set into a plurality of data segments; transforming the data in each data segment into a transformed data representation that comprises a band-type structure for each data segment, wherein said band-type structure comprises a plurality of bands; selecting a first set of bands, grouping them together and storing them with the original data set, wherein said first set of bands comprises non-identical transformed data for each data segment; selecting a second set of bands and grouping them together, wherein said second set of bands comprises identical transformed data for each data segment; applying a hash function onto the transformed data of the second set of bands and thereby generating transformed data segments indexed by hash function indices; storing the hash function indices and the transformed data representation of one representative data segment in a deduplication database.