Patent ID: 11882321
Assignee: ROKU, INC.
Field: Audio-visual technology (Electrical engineering)
Classification: CPC H  G | IPC G  H

Claim 16:
17. A non-transitory computer-readable medium storing instructions that, when executed by a processor of a media client device, cause the media client device to perform operations, the operations comprising:
ascertaining a plurality of matching points between (i) query fingerprints representing a media stream being received by the media client device and (ii) reference fingerprints, wherein the reference fingerprints are generated at a first frame rate and the query fingerprints are generated at a second frame rate lower than the first frame rate, and wherein each identified matching point defines a respective match between (i) a query fingerprint that is timestamped with client time defined according to a clock of the media client device and (ii) a reference fingerprint that is timestamped with true time according to a timeline within a known media stream,
wherein a first matching point of the plurality of matching points is based on analysis of a first bundle of query fingerprints at the second frame rate, wherein the first bundle comprises a match between some but not all query fingerprints of the first bundle at the second frame rate;
performing linear regression based on the timestamps of the ascertained plurality of matching points, the linear regression establishing a mapping of an offset between the true time and the client time; and
wherein the offset does not change more than a minimum threshold amount for an additional matching point factored into the linear regression, using the established mapping as a basis to determine a client-time point at which the media client device should perform an action with respect to the media stream being received by the media client device.