Dynamic control of fingerprinting rate to facilitate time-accurate revision of media content
A computing system identifies a media stream being received by a client, based on fingerprint matching conducted with query fingerprints generated by the client at a frame rate. The computing system then causes the client to increase the frame rate, in order to facilitate establishment by the computing system of synchronous lock between true time within the media stream and client time according to a clock of the client. The computing system then uses the established synchronous lock as a basis to map a true-time point at which a content revision should be performed in the media stream to a client-time point at which the client should perform the content revision. And the computing system causes the client to perform the content revision at the determined client-time point.
1. A method comprising:
generating query fingerprints representing a media stream being received by a client, wherein the query fingerprints are generated at a frame rate;
providing the generated query fingerprints for use to identify the media stream being received by the client based on comparison with reference fingerprints representing a known media stream;
after identification of the media stream being received by the client, increasing the frame rate of generating the query fingerprints;
providing the query fingerprints generated at the increased frame rate, for use to establish synchronous lock between (i) true-time defined along a timeline within the known media stream and (ii) client-time defined according to a clock of the client; and
performing, at a specific client-time point, a content revision of the media stream being received by the client, wherein the specific client-time point is determined based on the established synchronous lock.
2. The method of claim 1 , implemented by the client.
3. The method of claim 1 , wherein providing the generated query fingerprints for use to identify the media stream being received by the client based on comparison with reference fingerprints representing the known media stream comprises transmitting the generated query fingerprints to a server for use by the server to identify the media stream being received by the client based on comparison with reference fingerprints representing the known media stream.
4. The method of claim 3 , wherein increasing the frame rate of generating the query fingerprints after identification of the media stream being received by the client comprises:
after the server has identified the media stream being received by the client, receiving from the server a directive to increase the frame rate of generating the query fingerprints, and responsively increasing the frame rate of generating the query fingerprints.
5. The method of claim 1 , wherein providing the query fingerprints generated at the increased frame rate, for use to establish synchronous lock between true-time and client-time, comprises transmitting to a server the query fingerprints generated at the increased frame rate, for use by the server to establish the synchronous lock.
6. The method of claim 5 , wherein performing, at the specific client-time point determined based on the established synchronous lock, the content revision of the media stream being received by the client comprises:
receiving by the client from the server a content-revision directive directing the client to revise the media stream at the particular client-time point determined based on the established synchronous lock; and
carrying out by the client the revision of the media stream at the particular client-time point.
7. The method of claim 1 , wherein providing the query fingerprints generated at the increased frame rate, for use to establish synchronous lock between true-time and client-time, comprises providing the query fingerprints to a program module at the client for use by the program module at the client to establish the synchronous lock.
8. The method of claim 1 , further comprising using the query fingerprints generated at the increased frame rate as a basis to establish the synchronous lock between true-time and client-time.
9. The method of claim 8 , wherein using the query fingerprints generated at the increased frame rate as a basis to establish the synchronous lock between true-time and client-time comprises:
comparing the query fingerprints generated at the increased frame rate with reference fingerprints of the known media stream;
based on the comparing of the query fingerprints generated at the increased frame rate with the reference fingerprints of the known media stream, identifying at least one matching point defining a match between a query fingerprint and a reference fingerprint; and
establishing the synchronous lock based on a mapping between a client-time timestamp of the query fingerprint and a true-time timestamp of the reference fingerprint.
10. The method of claim 9 , implemented by the client, the method further comprising receiving by the client the reference fingerprints of the known media stream, to facilitate establishing the synchronous lock.
11. A computing system comprising:
a processing unit;
non-transitory data storage; and
program instructions stored in the non-transitory data storage and executable by the processing unit to cause the computing system to carry out operations including:
generating query fingerprints representing a media stream being received by a client, wherein the query fingerprints are generated at a frame rate,
providing the generated query fingerprints for use to identify the media stream being received by the client based on comparison with reference fingerprints representing a known media stream,
after identification of the media stream being received by the client, increasing the frame rate of generating the query fingerprints,
providing the query fingerprints generated at the increased frame rate, for use to establish synchronous lock between (i) true-time defined along a timeline within the known media stream and (ii) client-time defined according to a clock of the client, and
performing, at a specific client-time point, a content revision of the media stream being received by the client, wherein the specific client-time point is determined based on the established synchronous lock.
12. The computing system of claim 11 , disposed at the client.
13. The computing system of claim 11 , wherein providing the generated query fingerprints for use to identify the media stream being received by the client based on comparison with reference fingerprints representing a known media stream comprises transmitting the generated query fingerprints to a server for use by the server to identify the media stream being received by the client based on comparison with reference fingerprints representing the known media stream.
14. The computing system of claim 11 , wherein providing the query fingerprints generated at the increased frame rate, for use to establish synchronous lock between true-time and client-time, comprises transmitting to a server the query fingerprints generated at the increased frame rate, for use by the server to establish the synchronous lock.
15. The computing system of claim 14 , disposed at the client, wherein performing, at the specific client-time point determined based on the established synchronous lock, the content revision of the media stream being received by the client comprises:
receiving from the server a content-revision directive directing the client to revise the media stream at the particular client-time point determined based on the established synchronous lock; and
carrying out the revision of the media stream at the particular client time point.
16. The computing system of claim 11 , wherein the operations further include using the query fingerprints generated at the increased frame rate as a basis to establish the synchronous lock between true-time and client-time.
17. The computing system of claim 16 , wherein using the query fingerprints generated at the increased frame rate as a basis to establish the synchronous lock between true-time and client-time comprises:
comparing the query fingerprints generated at the increased frame rate with reference fingerprints of the known media stream;
based on the comparing of the query fingerprints generated at the increased frame rate with the reference fingerprints of the known media stream, identifying at least one matching point defining a match between a query fingerprint and a reference fingerprint; and
establishing the synchronous lock based on a mapping between a client-time timestamp of the query fingerprint and a true-time timestamp of the reference fingerprint.
18. The computing system of claim 17 , disposed at the client, wherein the operations further comprise receiving the reference fingerprints of the known media stream, to facilitate establishing the synchronous lock.
19. A non-transitory computer readable medium storing instructions executable by a processing unit to carry out operations comprising:
generating query fingerprints representing a media stream being received by a client, wherein the query fingerprints are generated at a frame rate;
providing the generated query fingerprints for use to identify the media stream being received by the client based on comparison with reference fingerprints representing a known media stream;
after identification of the media stream being received by the client, increasing the frame rate of generating the query fingerprints,
providing the query fingerprints generated at the increased frame rate, for use to establish synchronous lock between (i) true-time defined along a timeline within the known media stream and (ii) client-time defined according to a clock of the client; and
performing, at a specific client-time point, a content revision of the media stream being received by the client, wherein the specific client-time point is determined based on the established synchronous lock.
20. The non-transitory computer-readable medium of claim 19 , disposed at the client.