Algorithm for fast forward and fast rewind of MPEG streams

• US 6,097,422 A
• Filed: 10/05/1998
• Issued: 08/01/2000
• Est. Priority Date: 10/05/1998
• Status: Expired due to Fees

• Current Assignee: Matsushita Electric Corporation Of America (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Technologies, Inc. (Panasonic Holdings Corporation)
• Inventors: Mukherjee, Sarit, Kamel, Ibrahim Mostafa, Aref, Walid G.
• Primary Examiner(s): Kostak, Victor R.
• Application Number:
  US09/166,558
• Time in Patent Office: 666 Days
• Field of Search: 348/7, 348/12, 348/13, 348/6, 455/3.2, 455/4.2, 455/5.1, 204/217-219, 386/68
• US Class Current: 725/94
• 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 21/238 Interfacing the downstream path of the transmission network, e.g. adapting the transmission rate of a video stream to network bandwidth; Processing of multiplex streams hybrid fiber coaxial [HFC] networks for downstream channel allocation for video distribution H04L12/2801; flow control in packet networks H04L47/10; real-time communication protocols in data switching networks H04L65/00; scheduling or organising the servicing of application requests H04L67/60
• CPC Class Codes: H04N 21/2387 Stream processing in response to a playback request from an end-user, e.g. for trick-play
• 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 21/6377 directed to server one-way streaming services wherein the source is controlled by the destination H04L65/613
• CPC Class Codes: H04N 21/658 Transmission by the client directed to the server
• CPC Class Codes: H04N 21/6587 Control parameters, e.g. trick play commands, viewpoint selection
• CPC Class Codes: H04N 7/17318 Direct or substantially direct transmission and handling of requests

Abstract

A transport system allows delivery of MPEG video streams from a network server to a media client while avoiding network delays associated with transition between files contained in these streams. A buffering system, a transport controller, and a counter allow buffering and interim delivery of MPEG stream data. The transport controller can either deliver MPEG stream data directly to the media client, or route data through the buffering system. The buffering system includes a population buffer for storage of interim MPEG stream data, and a transport buffer for temporary storage of MPEG stream data during continuous delivery. During transitional delivery, the transport controller delivers interim data to the media client until the requested file is available and uses the counter to select the proper start location in the requested file.

Claims

1. A transport system for delivering MPEG stream data to a media client in response to a media request wherein said media request sets a delivery state of said transport system and said MPEG stream data contains I-frames, comprising:

a counter for tracking the position in the MPEG stream data of predetermined frames of data that are delivered, such that the counter is decremented during a rewind play mode;

a buffering system for storing said MPEG stream data; and

a transport controller for routing said MPEG stream data to said media client based on said delivery state and said counter.

2. The transport system of claim 1 wherein said media request sets said delivery state to transitional delivery.

3. The transport system of claim 2 wherein:

said media request comprises a request to transition from delivery of a forward express file to delivery of a normal play file such that said MPEG stream data comprises said forward express file and said normal play file, and said transport controller delivers interim I-frames contained in said forward express file to said media client in slow motion until said normal play file is available.

4. The transport system of claim 2 wherein said buffering system comprises:

a population buffer, said population buffer containing interim I-frames; and

a buffer read mechanism for reading said interim I-frames and delivering said interim I-frames to said media client.

5. The transport system of claim 4 wherein:

said media request comprises a request to transition from delivery of a normal play file to delivery of a forward express file such that said MPEG video data comprises said normal play file and said forward express file; and

said buffer read mechanism delivers said interim I-frames contained in said population buffer to said media client in fast forward speed until said forward express file is available.

6. The transport system of claim 4 wherein said transport controller adjusts said counter in relation to a number of said interim I-frames delivered to said media client from said population buffer.

7. The transport system of claim 6 wherein said media request comprises a request to transition to delivery of a rewind express file, and said transport controller reduces said counter by said number of said interim I-frames.

8. The transport system of claim 7 wherein:

said media request further comprises a request to transition from delivery of a normal play file such that said MPEG stream data comprises said normal play file and said reverse express file; and

said buffer read mechanism delivers said interim I-frames contained in said population buffer to said media client in fast forward speed until said reverse express file is available.

9. The transport system of claim 7 wherein:

said media request further comprises a request to transition from delivery of a forward express file such that said MPEG stream data comprises said forward express file and said reverse express file; and

said buffer read mechanism delivers said interim I-frames contained in said population buffer to said media client until said reverse express file is available.

10. The transport system of claim 6 wherein said media request comprises a request to transition from delivery of a rewind express file, and said transport controller increases said counter by said number of said interim I-frames.

11. The transport system of claim 10 wherein:

said media request further comprises a request to transition to delivery of a normal play file such that said MPEG stream data comprises said reverse express file and said normal play file; and

said buffer read mechanism delivers said interim I-frames contained in said population buffer to said media client in slow motion until said normal play file is available.

12. The transport system of claim 10 wherein:

said media request further comprises a request to transition to delivery of a forward express file such that said MPEG stream data comprises said reverse express file and said forward express file; and

said buffer read mechanism delivers said interim I-frames contained in said population buffer to said media client until said forward express file is available.

13. A transport system for delivering MPEG stream data to a media client in response to a media request wherein said media request sets a delivery state of said transport system to continuous delivery and said MPEG stream data contains I-frames, comprising:

a counter for tracking a number of delivered I-frames;

a buffering system for storing said MPEG stream data; and

a transport controller for routing said MPEG stream data to said media client based on said delivery state and said counter.

14. The transport system of claim 13 wherein said buffering system comprises:

a population buffer; and

a buffer write mechanism for storing said MPEG stream data in said population buffer.

15. The transport system of claim 14 wherein:

said media request comprises a request to deliver a forward express file such that said MPEG stream data comprises said forward express file; and

said transport controller routes said I-frames contained in said forward express file to said buffer write mechanism and directly to said media client.

16. The transport system of claim 14 wherein said buffering system further comprises:

a transport buffer for receiving said MPEG stream data from said buffer write mechanism; and

a buffer read mechanism for reading said MPEG stream data contained in said transport buffer and delivering said MPEG stream data to said media client.

17. The transport system of claim 16 wherein:

said media request comprises a request to deliver a normal play file such that said MPEG stream data comprises said normal play file; and

said transport controller routes said normal play file to said buffer write mechanism.

18. The transport system of claim 16 wherein:

said media request comprises a request to deliver a reverse express file such that said MPEG stream data comprises said reverse express file; and

said transport controller routes said I-frames contained in said reverse express file to said buffer write mechanism.

19. A method for delivering MPEG stream data to a media client in response to a media request wherein said media request sets a delivery state and said MPEG stream data comprises I-frames, comprising:

tracking a number of delivered I-frames;

storing interim I-frames of said MPEG stream data in a population buffer; and

routing said MPEG stream data to said media client based on said delivery state and said number of delivered I-frames.

20. The method of claim 19 wherein said media request sets said delivery state to transitional delivery.

21. The method of claim 20 wherein:

said media request comprises a request to transition from delivery of a forward express file to delivery of a normal play file such that said MPEG stream data comprises said forward express file and said normal play file; and

said routing step comprises delivering interim I-frames contained in said forward express file in slow motion until said normal play file is available.

22. The method of claim 20 wherein said population buffer wherein said routing step comprises delivering said interim I-frames to said media client.

23. A method for delivering MPEG stream data to a media client in response to a media request wherein said media request sets a delivery state of said transport system to continuous delivery and said MPEG stream data comprises I-frames, comprising:

tracking a number of delivered I-frames;

storing said MPEG stream data in a population buffer; and

routing said MPEG stream data to said media client based on said delivery state and said number of delivered I-frames.

24. The method of claim 23 wherein said media request comprises a request to deliver a forward express file such that said MPEG stream data comprises said forward express file, wherein said routing step comprises:

routing said I-frames contained in said forward express file to said population buffer; and

routing said I-frames contained in said forward express file directly to said media client.

25. The method of claim 23 wherein said routing step comprises:

storing said MPEG stream data in a transport buffer;

reading said MPEG stream data contained in said transport buffer; and

delivering said MPEG stream data to said media client.

26. The method of claim 25 wherein said media request comprises a request to deliver a normal play file such that said MPEG stream data comprises said normal play file.

27. The method of claim 25 wherein said media request comprises a request to deliver a reverse express file such that said MPEG stream data comprises said I-frames contained in said reverse express file.