Method and system for correlating data streams

• US 6,993,246 B1
• Filed: 09/15/2000
• Issued: 01/31/2006
• Est. Priority Date: 09/15/2000
• Status: Expired due to Fees

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Pan, Davis, Rehg, James M.
• Primary Examiner(s): Chevalier, Robert
• Application Number:
  US09/662,474
• Time in Patent Office: 1,964 Days
• Field of Search: 386/52, 386/55, 386/65, 386/109, 386/111, 386/112, 386/124, 386/125, 386/126, 386/46, 386/45, 386/40, 386/104, 386/105, 386/106, 386/22, 386/33, 386/28, 386/39, 704/211, 704/216
• US Class Current: 386/201
• CPC Class Codes: G11B 27/10 Indexing; Addressing; Timing or synchronising; Measuring tape travel
• CPC Class Codes: H04L 67/12 specially adapted for proprietary or special-purpose networking environments, e.g. medical networks, sensor networks, networks in vehicles or remote metering networks

Abstract

Events in a first data stream are correlated with events in a second data stream based on a method of indexing. As information of a first and second data stream are stored to a data file, the data streams are monitored for certain trigger events. An informational data set is generated and stored in an index file for each detected trigger event. Preferably, each informational data set includes the type of detected event, a time-stamp indicating when the event occurred and a data pointer indicating where the data associated with the event is stored in a corresponding data file. When time-stamps of detected trigger events in both data streams are generated based on a common system clock, data in one data stream is correlated with data in another data stream based on the time-stamps.

Claims

1. A method of correlating time sequenced data streams comprising computer implemented steps of:

identifying events within a first data stream;

generating positional information, also known as data pointers, for identified events;

assigning a time-stamp to each event; and

correlating data from the first data stream to data in a second data stream based on the time-stamped data pointers, wherein one of the first and second data streams includes audio data and has a playback rate dependent on detection of corresponding textual data in the other data stream.

2. A method as described in claim 1, wherein the time-stamps for events in the first data stream are generated by a system logger.

3. A method as described in claim 2, wherein the system logger time stamps data in the second data stream.

4. A computer method of correlating events in data streams comprising the steps of:

detecting events within a first data stream and assigning corresponding data pointers to the events;

detecting events within a second data stream and assigning corresponding data pointers to the events;

utilizing the data pointers to link events in the first data stream to events in the second data stream; and

assigning time-stamps to the events in the first data stream and in the second data stream to correlate events in the first data stream with events in the second data stream,

wherein the time-stamps assigned to events in the first data stream and in the second data stream are generated from separate but synchronized clocks.

5. A method as described in claim 4 further comprising the steps of:

identifying an event in the first data stream; and

locating of a corresponding event in the second data stream using the time-stamps as an index.

6. A method as described in claim 4, wherein the time-stamps assigned to events in the first data stream are generated from a system clock.

7. A method as described in claim 4, wherein the first data stream is asynchronous.

8. A method as described in claim 4 further comprising the step of:

presenting the first data stream with a time-varying playback rate.

9. A method as described in claim 4, wherein an event in the first data stream is defined by a fixed passage of time.

10. A method as described in claim 4, wherein the first data stream includes data generated by a word processor and the second data stream includes audio data.

11. A method as described in claim 4 further comprising the step of:

varying a rate of generating the first data stream relative to the second data stream based on detection of events in the second data stream.

12. A method as described in claim 4, wherein the first data stream includes audio data and has a playback rate dependent on detection of corresponding textual data in the second data stream.

13. A method as described in claim 4, wherein the events in the first stream are random events.

14. A method as described in claim 4 further comprising additional data streams in which events are correlated.

15. A method as described in claim 4, wherein the first data stream and second data stream are recorded to a storage device for later retrieval and the corresponding data pointers indicate a location of a corresponding event recorded in the storage device.

16. Computer apparatus for correlating time sequenced data streams comprising:

an event detector for identifying events within a first data stream and generating positional information for the identified events; and

a system logger for assigning a time-stamp to identified events and correlating the time-stamped data in the first data stream with a second data stream, wherein the first data stream includes audio data and has a playback rate dependent on detection of corresponding textual data in the second data stream.

17. An apparatus as described in claim 16, wherein the time-stamp is generated by a system logger.

18. An apparatus as described in claim 17, wherein the system logger time-stamps data in the second data stream.

19. An apparatus for correlating events in data streams comprising:

a first event detector for identifying events within a first data stream;

a second event detector for identifying events within a second data stream; and

a system logger that generates data pointers to correlate an event in the first data stream to an event in the second data stream, wherein the system logger assigns time-stamps to the events in the first data stream and the second data stream, and the time-stamps assigned to the first data stream and second data stream are generated from separate but synchronized clocks.

20. An apparatus as described in claim 19, wherein the time-stamps are used as an index to approximate a location of an event in one data stream to an event in another data stream.

21. An apparatus as described in claim 19, wherein the time-stamps assigned to the first data stream are generated from a system clock.

22. An apparatus as described in claim 19, wherein the first data stream is asynchronous.

23. An apparatus as described in claim 19 further comprising:

a playback device that generates the first data stream and varies a rate of a prerecorded data stream.

24. An apparatus as described in claim 19, wherein an event in the first data stream is defined by a fixed passage of time.

25. An apparatus as described in claim 19, wherein the first data stream includes data generated by a word processor and the second data stream includes audio data.

26. An apparatus as described in claim 19 further comprising means for varying a rate of the first data stream relative to the second data stream based on detection of events in the second data stream.

27. An apparatus as described in claim 19, wherein the first data stream includes audio data and has a playback rate dependent on detection of corresponding textual data in the second data stream.

28. An apparatus as described in claim 19, wherein the events in the first stream are random events.

29. An apparatus as described in claim 19, wherein additional data streams are correlated to the first data stream.

30. An apparatus as described in claim 19, wherein the first data stream and second data stream are recorded to a storage device for later retrieval and the corresponding data pointers indicate a location of a corresponding event recorded in the storage device.

31. A computer implemented method of correlating events in data streams comprising the steps of:

detecting events within a first data stream and assigning corresponding data pointers to the events;

detecting events within a second data stream and assigning corresponding data pointers to the events; and

utilizing the data pointers to link events in the first data stream to events in the second data stream, wherein the first data stream includes audio data and has a playback rate dependent on detection of corresponding textual data in the second data stream.

32. Computer apparatus for correlating events in data streams comprising:

a first event detector for identifying events within a first data stream;

a second event detector for identifying events within a second data stream;

a system logger that generates data pointers to correlate an event in the first data stream to an event in the second data stream; and

means for varying a rate of the first data stream relative to the second data stream based on detection of events in the second data stream.

33. Computer apparatus for correlating events in data streams comprising:

a first event detector for identifying events within a first data stream;

a second event detector for identifying events within a second data stream; and

a system logger that generates data pointers to correlate an event in the first data stream to an event in the second data stream, wherein the first data stream includes audio data and has a playback rate dependent on detection of corresponding textual data in the second data stream.