# US 8,542,870 B2 · Methods, apparatus and programs for generating and utilizing content signatures > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,542,870 B2 - Document ID: US8542870B2 - Status: Granted - Kind: B2 - Application number: 13/315,768 - Filed: 2011-12-09 - Published: 2012-03-29 - Granted: 2013-09-24 - Earliest claimed: 2000-12-21 - Assignees: Digimarc Corporation - Applicants: Hugh L. Brunk; Kenneth L. Levy - Inventors: Hugh L. Brunk; Kenneth L. Levy - Web page: https://patentgrep.com/patent/US8542870B2 ## CPC - H04N 19/467: characterised by the embedded information being invisible, e.g. watermarking - G06V 20/46: {Extracting features or characteristics from the video content, e.g. video fingerprints, representative shots or key frames} - H04N 19/48: using compressed domain processing techniques other than decoding, e.g. modification of transform coefficients, variable length coding [VLC] data or run-length data (motion estimation in a transform domain H04N19/547; processing of decoded motion vectors H04N19/513) - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION - G06V: IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING ## Abstract The presently claimed invention generally relates to deriving and/or utilizing content signatures (e.g., so-called “fingerprints”). One claim recites a method of generating a fingerprint associated with a content item including: pseudo-randomly selecting a segment of the content item; and utilizing a processor or electronic processing circuitry, fingerprinting the selected segment of content item as at least an identifier of the content item. Of course, other claims and combination are provided as well. ## Claims ### Claim 1 A method comprising: pseudo-randomly selecting a segment of a content item; and utilizing a processor or electronic processing circuitry, fingerprinting the selected segment of the content item as at least an identifier of the content item, wherein the fingerprinting comprises at least one type of fingerprinting selected from a group of fingerprinting comprising: evaluating perceptually relevant features, a frequency domain analysis, hashing and a lossy transformation. ### Claim 2 (depends on 1) The method of claim 1, wherein the segment is pseudo-randomly selected based on a known key. ### Claim 3 (depends on 2) The method of claim 2, wherein the known key comprises a user identifier. ### Claim 4 (depends on 1) The method of claim 1, wherein the content item comprises video. ### Claim 5 (depends on 1) The method of claim 1, wherein the content item comprises audio. ### Claim 6 (depends on 1) The method of claim 1, further comprising deriving a content signature for the content item from data within the selected segment. ### Claim 7 (depends on 6) The method of claim 6, further comprising comparing the derived content signature with a stored signature, wherein failure to match indicates the content item has been altered. ### Claim 8 An apparatus comprising: a processor; and memory comprising instructions for execution by the processor, wherein the instructions are configured to: pseudo-randomly select a segment of a content item; and derive a fingerprint from the selected segment of the content item as at least an identifier of the content item, wherein the fingerprint comprises at least one type of fingerprint selected from a group of fingerprints comprising: perceptually relevant features, a frequency domain analysis, hashing and a lossy transformation. ### Claim 9 (depends on 8) The apparatus of claim 8, wherein the segment is pseudo-randomly selected based on a known key. ### Claim 10 (depends on 9) The apparatus of claim 9, wherein the known key comprises a user identifier. ### Claim 11 (depends on 8) The apparatus of claim 8, wherein the content item comprises video. ### Claim 12 (depends on 8) The apparatus of claim 8, wherein the content item comprises audio. ### Claim 13 (depends on 8) The apparatus of claim 8, wherein the instructions are further configured to derive a content signature for the content item from data within the selected segment. ### Claim 14 (depends on 13) The apparatus of claim 13, wherein the instructions are further configured to compare the derived content signature with a stored signature, wherein failure to match indicates the content item has been altered. ### Claim 15 A tangible computer-readable medium having instructions stored thereon, the instructions comprising: instructions to pseudo-randomly select a segment of a content item; and instructions to fingerprint the selected segment of the content item as at least an identifier of the content item, wherein the fingerprint comprises at least one type of fingerprint selected from a group of fingerprints comprising: perceptually relevant features, a frequency domain analysis, hashing and a lossy transformation. ### Claim 16 (depends on 15) The tangible computer-readable medium of claim 15, wherein the segment is pseudo-randomly selected based on a known key. ### Claim 17 (depends on 16) The tangible computer-readable medium of claim 16, wherein the known key comprises a user identifier. ### Claim 18 (depends on 15) The tangible computer-readable medium of claim 15, wherein the content item comprises audio. ### Claim 19 (depends on 15) The tangible computer-readable medium of claim 15, wherein the instructions are further configured to derive a content signature for the content item from data within the selected segment. ### Claim 20 (depends on 19) The tangible computer-readable medium of claim 19, wherein the instructions are further configured to compare the derived content signature with a stored signature, wherein failure to match indicates the content item has been altered.