System for synchronization with nonstreaming device controller and a streaming data handler each supplying current location for synchronizing slave data and master data flow

• US 5,832,309 A
• Filed: 12/04/1996
• Issued: 11/03/1998
• Est. Priority Date: 11/10/1994
• Status: Expired due to Fees

• Current Assignee: Lenovo Singapore Pte Limited (Lenovo Group Ltd.)
• Original Assignee: International Business Machines Corporation
• Inventors: Koval, Michael Joseph, Killian, David William, Noe, Bradley Dale, Lawton, William Wallis
• Primary Examiner(s): Lee, Thomas C.
• Assistant Examiner(s): Chen, Anderson I.
• Application Number:
  US08/760,172
• Time in Patent Office: 699 Days
• Field of Search: 364/238.3, 395/200, 395/550, 395/650
• US Class Current: 710/61
• CPC Class Codes: G11B 2220/20 Disc-shaped record carriers
• CPC Class Codes: G11B 2220/2587 Laser Discs; Optical disc using analog recording
• CPC Class Codes: G11B 2220/90 Tape-like record carriers
• CPC Class Codes: G11B 27/002 Programmed access in sequence to a plurality of record carriers or indexed parts, e.g. tracks, thereof, e.g. for editing; transfer of record carriers from magazine G11B15/68, G11B17/10; G11B17/22
• CPC Class Codes: G11B 27/10 Indexing; Addressing; Timing or synchronising; Measuring tape travel

Abstract

Disclosed are apparatus and methods for synchronized presentation of analog and digital data by applying a common synchronization scheme to both types of data. Digital data is "streamed" by transferring the data in blocks from a source to a series of memory buffers, where it accumulates for subsequent transfer to an output device driver. The control module responsible for data streaming periodically reports a temporal location within the presentation represented by the data. A supervisory module designates one of the control modules a "master", and periodically compares the values reported by the various other control modules against that reported by the master. If a comparison exceeds a threshold tolerance value associated with each control module, a sync pulse is delivered to that control module, causing it to correct the synchronization mismatch.

This approach is applied to analog sources through the use of control modules that behave in a manner consistent with the digital control modules, but which are capable of directing the operation of analog devices and re-establishing their synchronization with other data sources despite limited modes of device control. Specifically, the control modules that handle analog information also periodically report a presentation location based solely on temporal information, react to sync pulses by altering the playback rate of the analog devices they control within user-tolerable limits, and can act as master control modules.

Claims

1. An apparatus for synchronizing the presentation of streaming and non-streaming data within at least one output device, said apparatus comprising:

comparison means for comparing a current temporal location of non-streaming data being transferred to said at least one output device with a current temporal location of streaming data being transferred to said at least one output device to determine a synchronization-mismatch value, wherein one of said non-streaming data and said streaming data comprises a master data flow and the other of said non-streaming data and said streaming-data comprises a slave data flow;

synchronization means for synchronizing said current temporal location of said slave data flow with said current temporal location of said master data flow based on said synchronization-mismatch value, wherein said synchronization means includes a non-streaming device controller that controls a rate at which said non-streaming data is transferred to said at least one output device and supplies information indicative of said current temporal location of said non-streaming data to said comparison means;

a streaming data handler, wherein said streaming data handler receives said streaming data from at least one streaming data source and outputs said streaming data to said at least one output device, and wherein said streaming data handler supplies information indicative of said current temporal location of said streaming data to said comparison means, said streaming data handler including;

at least one data buffer;

an output device driver;

first transfer means for loading said streaming data into said at least one data buffer as a first data stream; and

second transfer means for extracting said streaming data from said data buffer as a second data stream and for transferring said streaming data to said output device driver, said first and second transfer means interoperating to ensure a continuous queue of streaming data in said data buffer.

2. The apparatus of claim 1, wherein:

said streaming data handler and said non-streaming device controller each include means for periodically generating synchronization pulses, wherein each of said means for periodically generating synchronization pulses is operative only if an associated one of said streaming data and said non-streaming data is designated as said master data flow; and

said synchronization means further includes means for directing at least one of said synchronization pulses from the one of said streaming data handler and said non-streaming device controller associated within said master data flow to the other of said streaming data handler and said non-streaming device controller that is associated with said slave data flow.

3. The apparatus of claim 2, wherein said synchronization means includes selection means for selecting as said master data flow one of said streaming data and said non-streaming data, wherein said selection is made in response to which of said streaming data handler and said non-streaming device controller generates synchronization pulses at a higher frequency.

4. The apparatus of claim 1, wherein said non-streaming data is provided by at least one non-streaming data source having a controllable play speed, and wherein said non-streaming device controller corrects said play speed to correct a synchronization mismatch in response to a synchronization signal.

5. The apparatus of claim 1, wherein said comparison means comprises comparison means for comparing a current temporal location of non-streaming data being transferred to said at least one output device in analog format with a current temporal location of streaming data being transferred to said at least one output device in digital format to determine a synchronization-mismatch value.

6. A presentation system that synchronizes the presentation of streaming and non-streaming data, said presentation system comprising:

a streaming data source that produces streaming data and a non-streaming data source that produces non-streaming data;

at least one output device for presenting said streaming and said non-streaming data;

comparison means for comparing a current temporal location of said non-streaming data with a current temporal location of streaming data to determine a synchronization-mismatch value, wherein one of said non-streaming data and said streaming data comprises a master data flow and the other of said non-streaming data and said streaming-data comprises a slave data flow;

synchronization means for synchronizing said current temporal location of said slave data flow with said current temporal location of said master data flow based on said synchronization-mismatch value, wherein said synchronization means includes a non-streaming device controller that controls a rate at which said non-streaming data is transferred to said at least one output device and supplies information indicative of said current temporal location of said non-streaming data to said comparison means;

a streaming data handler, wherein said streaming data handler receives said streaming data from at least one streaming data source and outputs said streaming data to said at least one output device, and wherein said streaming data handler supplies information indicative of said current temporal location of said streaming data to said comparison means, said streaming data handler including;

at least one data buffer;

an output device driver;

first transfer means for loading said streaming data into said at least one data buffer as a first data stream; and

second transfer means for extracting said streaming data from said data buffer as a second data stream and for transferring said streaming data to said output device driver, said first and second transfer means interoperating to ensure a continuous queue of streaming data in said data buffer.

7. The presentation system of claim 6, wherein:

said streaming data handler and said non-streaming device controller each include means for periodically generating synchronization pulses, wherein each of said means for periodically generating synchronization pulses is operative only if an associated one of said streaming data and said non-streaming data is designated as said master data flow; and

said synchronization means further includes means for directing at least one of said synchronization pulses from the one of said streaming data handler and said non-streaming device controller associated within said master data flow to the other of said streaming data handler and said non-streaming device controller that is associated with said slave data flow.

8. The presentation system of claim 7, wherein said synchronization means includes selection means for selecting as said master data flow one of said streaming data and said non-streaming data, wherein said selection is made in response to which of said streaming data handler and said non-streaming device controller generates synchronization pulses at a higher frequency.

9. The presentation system of claim 6, said non-streaming data source having a controllable play speed, wherein said non-streaming device controller corrects said play speed to correct a synchronization mismatch in response to a synchronization signal.

10. The presentation system of claim 6, wherein said comparison means comprises comparison means for comparing a current temporal location of non-streaming data being transferred to said at least one output device in analog format with a current temporal location of streaming data being transferred to said at least one output device in digital format to determine a synchronization-mismatch value.

11. A computer program product for use with a data processing system having at least one output device and sources of streaming and non-streaming data, said computer program product comprising:

comparison instruction code for causing said data processing system to compare a current temporal location of non-streaming data being transferred to said at least one output device with a current temporal location of streaming data being transferred to said at least one output device to determine a synchronization-mismatch value, wherein one of said non-streaming data and said streaming data comprises a master data flow and the other of said non-streaming data and said streaming-data comprises a slave data flow;

synchronization instruction code for causing said data processing system to synchronize said current temporal location of said slave data flow with said current temporal location of said master data flow based on said synchronization-mismatch value, wherein said synchronization instruction code includes a non-streaming device controller that controls a rate at which said non-streaming data is transferred to said at least one output device and supplies information indicative of said current temporal location of said non-streaming data to said comparison instruction code;

a streaming data handler, wherein said streaming data handler receives said streaming data from at least one streaming data source and outputs said streaming data to said at least one output device, and wherein said streaming data handler supplies information indicative of said current temporal location of said streaming data to said comparison instruction code, said streaming data handler including;

an output device driver;

first transfer means for loading said streaming data into a data buffer as a first data stream; and

second transfer means for extracting said streaming data from said data buffer as a second data stream and for transferring said streaming data to said output device driver, said first and second transfer means interoperating to ensure a continuous queue of streaming data in the data buffer; and

signal bearing media bearing said comparison instruction code, said synchronization instruction code, and said streaming data handler.

12. The computer program product of claim 11, wherein:

said streaming data handler and said non-streaming device controller each include means for periodically generating synchronization pulses, wherein each of said means for periodically generating synchronization pulses is operative only if an associated one of said streaming data and said non-streaming data is designated as said master data flow; and

said synchronization instruction code further includes means for directing at least one of said synchronization pulses from the one of said streaming data handler and said non-streaming device controller associated within said master data flow to the other of said streaming data handler and said non-streaming device controller that is associated with said slave data flow.

13. The computer program product of claim 12, wherein said synchronization instruction code includes selection means for selecting as said master data flow one of said streaming data and said non-streaming data, wherein said selection is made in response to which of said streaming data handler and said non-streaming device controller generates synchronization pulses at a higher frequency.

14. The computer program product of claim 11, wherein said source of said non-streaming data has a controllable play speed, and wherein said non-streaming device controller corrects said play speed to correct a synchronization mismatch in response to a synchronization signal.

15. The computer program product of claim 11, wherein said comparison instruction code comprises comparison instruction code for causing said data processing system to compare a current temporal location of non-streaming data being transferred to said at least one output device in analog format with a current temporal location of streaming data being transferred to said at least one output device in digital format to determine a synchronization-mismatch value.