Dynamic stream interleaving and sub-stream based delivery

• US 9,178,535 B2
• Filed: 04/15/2008
• Issued: 11/03/2015
• Est. Priority Date: 06/09/2006
• Status: Expired due to Fees

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Digital Fountain Incorporated (Qualcomm, Inc.)
• Inventors: Luby, Michael G., Pakzad, Payam, Watson, Mark, Vicisano, Lorenzo, Clish, Jourdan J.
• Primary Examiner(s): Lohn, Joshua
• Application Number:
  US12/103,605
• Publication Number:
  US 20080256418A1
• Time in Patent Office: 2,758 Days
• Field of Search: 714/774, 714/776
• US Class Current: 1/1
• CPC Class Codes: H03M 13/1102 Codes on graphs and decoding on graphs, e.g. low-density parity check [LDPC] codes
• CPC Class Codes: H03M 13/15 Cyclic codes, i.e. cyclic shifts of codewords produce other codewords, e.g. codes defined by a generator polynomial, Bose-Chaudhuri-Hocquenghem [BCH] codes H03M13/17 takes precedence
• CPC Class Codes: H03M 13/1515 Reed-Solomon codes
• CPC Class Codes: H03M 13/27 using interleaving techniques
• CPC Class Codes: H03M 13/2789 Interleaver providing variable interleaving, e.g. variable block sizes
• CPC Class Codes: H03M 13/353 Adaptation to the channel
• CPC Class Codes: H03M 13/373 with erasure correction and erasure determination, e.g. for packet loss recovery or setting of erasures for the decoding of Reed-Solomon codes
• CPC Class Codes: H03M 13/3761 using code combining, i.e. using combining of codeword portions which may have been transmitted separately, e.g. Digital Fountain codes, Raptor codes or Luby Transform [LT] codes
• CPC Class Codes: H03M 13/6508 Flexibility, adaptability, parametrability and configurability of the implementation
• CPC Class Codes: H04L 1/0071 Use of interleaving interleaving per se H03M13/27

Abstract

A communications system can provide methods of dynamically interleaving streams, including methods for dynamically introducing greater amounts of interleaving as a stream is transmitted independently of any source block structure to spread out losses or errors in the channel over a much larger period of time within the original stream than if interleaving were not introduced, provide superior protection against packet loss or packet corruption when used with FEC coding, provide superior protection against network jitter, and allow content zapping time and the content transition time to be reduced to a minimum and minimal content transition times. Streams may be partitioned into sub-streams, delivering the sub-streams to receivers along different paths through a network and receiving concurrently different sub-streams at a receiver sent from potentially different servers. When used in conjunction with FEC encoding, the methods include delivering portions of an encoding of each source block from potentially different servers.

Claims

1. In a communication system, a method of transmitting content streams comprising:

forming a connection between a receiver and a first sender;

forming a connection between the receiver and a second sender;

receiving at the receiver a first content stream transmitted from the first sender, wherein the first content stream contains a first initial amount of interleaving;

receiving at the receiver a second content stream transmitted from the second sender, wherein the second content stream contains a second initial amount of interleaving;

adjusting the amount of interleaving contained in the first content stream during the transmission of the first content stream independently of the source block structure of the first content stream, increasing the amount of interleaving from the first initial amount of interleaving, based on a current transmit position within the first content stream; and

adjusting the amount of interleaving contained in the second content stream during the transmission of the second content stream independently of the source block structure of the second content stream, increasing the amount of interleaving from the second initial amount of interleaving, based on a current transmit position within the second content stream,

wherein the amount of interleaving contained in each of the first and second content streams is independent of the amount of interleaving contained in the other of the first and second content streams.

2. The method of claim 1 wherein the first initial amount of interleaving in the first content stream is configured so that there is no initial interleaving in the first content stream.

3. The method of claim 1 wherein the amount of interleaving in the first content stream is adjusted from the first initial amount to a steady state amount.

4. The method of claim 3 wherein the interleaving in the first content stream linearly transitions between the first initial amount and the steady state amount.

5. The method of claim 1 wherein the amount of interleaving contained in the first content stream is adjusted as a function of time.

6. The method of claim 1 wherein the amount of interleaving contained in the first content stream is adjusted as a function of the difference between the playback rate of the first content stream and the transmission rate of the first content stream.

7. The method of claim 1 wherein the amount of interleaving contained in the first content stream is adjusted as a function of the amount of data loss experienced at the receiver.

8. The method of claim 1 wherein the source block structure of the first content stream does not change during the transmission of the first content stream.

9. The method of claim 1 further comprising:

building a reserve buffer of content from the first content stream.

10. The method of claim 9 wherein the reserve buffer is built concurrently with any adjustments made to the amount of interleaving in the first content stream.

11. The method of claim 1 further comprising

transitioning between the first content stream and the second content stream in a manner that keeps the aggregate transmission rate of the first and second content streams approximately level.

12. The method of claim 11 wherein the transition between the first content stream and the second content stream is carried out over time as a function of the amount of interleaving contained in the first and second content streams.

13. In a receiver that receives data over a channel, a method of receiving content streams comprising:

forming a connection between a receiver and a first sender;

forming a connection between the receiver and a second sender;

receiving a first content stream transmitted from the first sender, wherein the first content stream contains a first initial amount of interleaving that can be adjusted during the transmission of the first content stream independently of the source block structure of the first content stream, the amount of interleaving increasing from the first initial amount of interleaving, based on a current transmit position within the first content stream; and

receiving a second content stream transmitted from the second sender, wherein the second content stream contains a second initial amount of interleaving that can be adjusted during the transmission of the second content stream independently of the source block structure of the second content stream, the amount of interleaving increasing from the second initial amount of interleaving, based on a current transmit position within the second content stream,

wherein the amount of interleaving contained in each of the first and second content streams is independent of the amount of interleaving contained in the other of the first and second content streams.

14. In a communication system, a method of transmitting a content stream comprising:

forming a connection between a receiver and a plurality of senders;

receiving at the receiver a content stream transmitted from the plurality of senders, wherein each sender transmits a different content sub-stream of the content stream to the receiver and each content sub-stream contains an initial amount of interleaving; and

adjusting the amount of interleaving contained in each content sub-stream during the transmission of the content sub-streams independently of the source block structure of the content sub-streams, increasing the amount of interleaving in each content sub-stream from the initial amount of interleaving, based on a current transmit position within each content sub-stream,

wherein the amount of interleaving contained in each content sub-stream is independent of the amount of interleaving contained in the other content sub-streams.

15. The method of claim 14 wherein the source block structure of the content sub-streams does not change during the transmission of the content sub-streams.

16. An apparatus for receiving a content stream transmitted from a plurality of senders, the apparatus comprising:

a receive module configured to receive the content stream transmitted from the plurality of senders, wherein each sender transmits a different content sub-stream of the content stream to the receiver and each content sub-stream contains an initial amount of interleaving that can be adjusted during the transmission of the content sub-stream independently of the source block structure of the content sub-stream, the amount of interleaving of each content sub-stream increasing from the initial amount of interleaving, based on a current transmit position within the content sub-stream stream,

wherein the amount of interleaving contained in each content sub-stream is independent of the amount of interleaving contained in the other content sub-streams.

17. A communication system for transmitting a content stream, the system comprising:

a plurality of senders, each sender configured to transmit a different content sub-stream of the content stream to a receiver, wherein each content sub-stream contains an initial amount of interleaving; and

the receiver configured to receive the content stream transmitted from the plurality of senders,

wherein the amount of interleaving contained in each content sub-stream is adjusted during the transmission of the content sub-streams independently of the source block structure of the content sub-streams, the amount of interleaving in each content sub-stream increasing from the initial amount of interleaving, based on a current transmit position within each content sub-stream,

wherein the amount of interleaving contained in each content sub-stream is independent of the amount of interleaving contained in the other content sub-streams.