New patents are issued by the USPTO on Tuesdays. Today's Spotlight Patents address various aspects of digital fingerprinting and digital watermarking. Assigned to Google, the first patent concerns techniques for using logical block addresses with generation numbers as data fingerprints for network deduplication. Assigned to Digitmarc, the second patent concerns techniques for content recognition employing fingerprinting at different resolutions.
9,280,288, "Using logical block addresses with generation numbers as data fingerprints for network deduplication," assigned to Google.
The technique introduced here involves using a block address and a corresponding generation number as a "fingerprint" to uniquely identify a sequence of data within a given storage domain. Each block address has an associated generation number which indicates the number of times that data at that block address has been modified. This technique can be employed, for example, to determine whether a given storage server already has the data, and to avoid sending the data to that storage server over a network if it already has the data. It can also be employed to maintain cache coherency among multiple storage nodes.
9,280,977, "Content recognition employing fingerprinting at different resolutions," assigned to Digimarc.
Content fingerprints and watermarks are combined in various ways for content identification applications. Fingerprints are used to identify content generally while watermarks provide more detailed localization of parts within the content, and vice versa. Fingerprint techniques are further used for signal synchronization and other pre-processing steps to assist in digital watermark decoding. A variety of fingerprint/watermark techniques identify characteristics of the channel of content from content samples.