System and method for media stream indexing and synchronization

• US 7,272,780 B2
• Filed: 09/02/2005
• Issued: 09/18/2007
• Est. Priority Date: 03/31/1997
• Status: Expired due to Fees

• Current Assignee: Espial Incorporated (Enghouse Systems Limited)
• Original Assignee: Kasenna, Inc. (Enghouse Systems Limited)
• Inventors: Smith, Kevin P., Abbott, Michael J., Close, Paul
• Primary Examiner(s): Hong; Stephen
• Assistant Examiner(s): LUDWIG, MATTHEW J
• Application Number:
  US11/219,341
• Publication Number:
  US 20060101322A1
• Time in Patent Office: 746 Days
• Field of Search: 715/500.1, 715/501.1, 715/513, 715/522, 715/723, 715/721, 715/731, 715/732
• US Class Current: 715/203
• CPC Class Codes: H04N 21/23424 involving splicing one content stream with another content stream, e.g. for inserting or substituting an advertisement
• CPC Class Codes: H04N 21/2368 Multiplexing of audio and video streams
• CPC Class Codes: H04N 21/4305 Synchronising client clock from received content stream, e.g. locking decoder clock with encoder clock, extraction of the PCR packets arrangements for synchronising receiver with transmitter by comparing receiver clock with transmitter clock H04L7/0012; arrangements for synchronising receiver with transmitter wherein the receiver takes measures against momentary loss of synchronisation H04L7/0083
• CPC Class Codes: H04N 21/4331 Caching operations, e.g. of an advertisement for later insertion during playback
• CPC Class Codes: H04N 21/4341 Demultiplexing of audio and video streams
• CPC Class Codes: H04N 21/44016 involving splicing one content stream with another content stream, e.g. for substituting a video clip
• CPC Class Codes: H04N 21/47202 for requesting content on demand, e.g. video on demand
• CPC Class Codes: H04N 21/812 involving advertisement data advertising per se G06Q30/02
• CPC Class Codes: H04N 21/8146 involving graphical data, e.g. 3D object, 2D graphics
• CPC Class Codes: H04N 21/8455 involving pointers to the content, e.g. pointers to the I-frames of the video stream
• CPC Class Codes: H04N 21/8456 by decomposing the content in the time domain, e.g. in time segments
• CPC Class Codes: H04N 21/8547 involving timestamps for synchronizing content
• CPC Class Codes: H04N 7/17318 Direct or substantially direct transmission and handling of requests

Abstract

An indexing method for allowing a viewer to control the mode of delivery of program material. By mapping from time to data position, data delivery can begin at any selected time in the program material. The indexing method also provides for controlling data delivery to begin at the beginning of a frame of data. A synchronizing method is provided to minimize a time offset between audio and vide data, particularly in environments using groups of pictures.

Claims

1. A system for interactive delivery of program material to a viewer, comprising a processor coupled with a memory:

formatting means operatively coupled with said processor for arranging media data representing program material intended for transmission to a viewer in an interactive and customized manner in accordance with a received format command, said formatting means for arranging media data arranges the media data without a need for modifying, changing, or duplicating the program material in a separate storage, wherein said media data is identified and arranged using an object hierarchy that comprises;

segments, wherein each of said segments is assigned a unique seqment ID when it is stored and references a correspondinq atom of media data and is defined by an offset from a beginning of said corresponding atom, and a duration;

series, wherein each of said series is assigned a unique series ID when the series is stored and comprises at least one segment, and when including a plurality of segments is formed by sequentially ordering the plurality of seqments joined or concatenated for sequential delivery of the corresponding data; and

groups, wherein each of said group is assigned a unique group ID when the group is stored and comprises at least one series, and when a group includes a plurality of series is formed by ioining the plurality of series in parallel for parallel simultaneous delivery of the corresponding data; and

each said group comprises at least one series, each said series comprises at least one segment, and each said segment references at least a portion of an atom of media data and said group defines a formula for arranging said program material to be delivered to a viewer.

2. The system of claim 1, further comprising:

means for converting a program material time to a data location for media data.

3. The system of claim 1, wherein said formatting means comprises:

a server at a location remote from the viewer.

4. A system for interactive delivery of program material to a viewer, comprising a processor coupled with a memory:

formatting means operatively coupled with said processor for arranging media data representing program material intended for transmission to a viewer in an interactive and customized manner in accordance with a received format command, wherein said media data is identified and arranged using an object hierarchy, the object hierarchy defining a plurality of series in a group that may be transmitted and delivered simultaneously to a viewer in parallel, and wherein any one of said plurality of series can be turned on or off at any specified time, the object hierarchy further comprises;

segments, wherein each of said segments is assigned a unique segment ID when it is stored and references a corresponding atom of media data and is defined by an offset from a beginning of said corresponding atom, and a duration;

series, wherein each of said series is assigned a unique series ID when the series is stored and comprises at least one segment, and when including a plurality of segments is formed by sequentially ordering the plurality of segments joined or concatenated for sequential delivery of the corresponding data; and

groups, wherein each of said group is assigned a unique group ID when the group is stored and comprises at least one series, and when a group includes a plurality of series is formed by joining the plurality of series in parallel for parallel simultaneous delivery of the corresponding data; and

each said group comprises at least one series, each said series comprises at least one segment, and each said segment references at least a portion of an atom of media data and said group defines a formula for arranging said program material to be delivered to a viewer.

5. A system for interactive delivery of program material to a viewer, comprising a processor coupled with a memory:

means operatively coupled with said processor for converting a program material time to a data location for media data;

formatting means for arranging media data representing program material intended for transmission to a viewer in an interactive and customized manner in accordance with a received format command, wherein said media data is identified and arranged using an object hierarchy that comprises;

segments, wherein each of said segments is assigned a unigue segment ID when it is stored and references a corresponding atom of media data and is defined by an offset from a beginning of said corresponding atom, and a duration;

series, wherein each of said series is assigned a unigue series ID when the series is stored and comprises at least one segment, and when including a plurality of segments is formed by seguentially ordering the plurality of segments joined or concatenated for seguential delivery of the corresponding data; and

groups, wherein each of said group is assigned a unigue group ID when the group is stored and comprises at least one series, and when a group includes a plurality of series is formed by joining the plurality of series in parallel for parallel simultaneous delivery of the corresponding data; and

each said group comprises at least one series, each said series comprises at least one segment, and each said segment references at least a portion of an atom of media data and said group defines a formula for arranging said program material to be delivered to a viewer; and

said means for converting a program material time to a data location for media data comprises means for converting from program material relative time to a media data atom-relative byte position;

wherein the atom-relative byte position corresponds to a beginning of a frame for the media data, an atom index file includes frame-partitioned data and includes byte offsets so that the atom relative byte position in the index file corresponds frame boundaries.

6. A system as in claim 5, wherein the atom index file is constructed by parsing the encoded data to identify index boundaries suitable for a selected encoding scheme.

7. A system as in claim 6, wherein the selected encoding scheme is selected from the set of encoding schemes consisting of MPEG-1 encoded video data, MPEG-1 encoded audio data, and MPEG-2 encoded audio and video data.

8. A method for locating program material at a specified time T, comprising:

converting the specified time T to a time T_rel, relative to media data representing the program material;

determining an index number from said time T_rel using an index duration;

converting said index number to a data position, thereby locating media data representing the program material at the specified time T;

converting Tseq to a data position relative to a specified atom, thereby locating media data representing the program material at the specified time T; and

converting T_seg to a specified-atom relative time T_atom by adding the specified-segment offset to T_seg, and computing an index number from T_atom using an index duration.

9. The method of claim 8, wherein said index duration is a duration of one frame of media data.

10. The method of claim 8, further comprising:

rounding said index number to locate an index boundary.

11. The method of claim 10, wherein said index boundary is a beginning of a frame of media data.

12. The method of claim 10, wherein said index boundary is a beginning of a group of pictures of media data.

13. A method as in claim 8, wherein the method for locating program material comprises locating the program material so that delivery of the program material to a viewer via media delivery on demand begins at the specified time T in the program material.

14. A method as in claim 8, further comprising accessing a group having one or more series, each series having one or more segments that references a corresponding atom containing the media data representing the program material.

15. A method as in claim 14, further comprising determining in which specified segment of which specified atom of media data the specified time T occurs.

16. A method as in claim 15, further comprising converting the specified time T to a specified-segment relative time T_seg by calculating an elapsed time into the specified segment at which the specified time occurs.

17. A method as in claim 8, wherein the index duration is the duration of a frame of media data.

18. A method as in claim 17, wherein the index number is used to identify a data position for the media data representing the program material at the specified time T.

19. A method as in claim 8, wherein an index file is used to correlate index number with a corresponding data position.

20. A method as in claim 19, wherein the corresponding data positions are the beginning of a frame of media data, or the beginning of a group of media items of media data.

21. A method as in claim 20, wherein the media items include pictures.

22. A computer program product stored on a computer readable medium for use with a computer system and a content on demand media delivery system including a computer readable program code for enabling a computer system to carry out the locating of program material so that delivery of the program material to a viewer via media delivery on demand begins at the specified time T in the program material;

the computer program product including instructions for;

converting the specified time T to a time T_rel, relative to media data representing the program material;

determining an index number from said time T_rel using an index duration; and

converting said index number to a data position, thereby locating media date representing the program material at the specified time T;

converting Tseq to a data position relative to a specified atom, thereby locating media data representing the program material at the specified time T; and

converting T_seg to a specified-atom relative time T_atom by adding the specified-segment offset to T_seg, and computing an index number from T_atom using an index duration.