Correction data

• US 9,276,606 B2
• Filed: 11/01/2012
• Issued: 03/01/2016
• Est. Priority Date: 06/18/2012
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Inventors: Vafin, Renat, Andersen, Soren Vang, Nilsson, Mattias
• Primary Examiner(s): Decady, Albert
• Assistant Examiner(s): ALSHACK, OSMAN M
• Application Number:
  US13/666,774
• Publication Number:
  US 20130339824A1
• Time in Patent Office: 1,216 Days
• Field of Search: 714/752, 714/758, 714/776
• US Class Current: 1/1
• CPC Class Codes: H03M 13/05 using block codes, i.e. a predetermined number of check bits joined to a predetermined number of information bits H03M13/2906 takes precedence
• CPC Class Codes: H03M 13/11 using multiple parity bits
• CPC Class Codes: H03M 13/27 using interleaving techniques
• CPC Class Codes: H04L 1/0041 Arrangements at the transmitter end
• CPC Class Codes: H04L 1/0055 MAP-decoding
• CPC Class Codes: H04L 1/0057 Block codes H04L1/0061, H04L1/0064 take precedence

Abstract

Various embodiments provide a method for processing encoded data bits transmitted over a lossy communication channel. In some embodiments, the method receives the encoded data bits over the communication channel, the encoded data bits including redundant data units; decodes the encoded data bits at an error correction decoder, wherein the recovery of lost data is implemented at the error correction decoder using at least one of the redundant data units; determining if at least one data bit is unable to be recovered due to the decoder finding a plurality of candidate bit values for the at least one data bit; receives information relating to the transmitter; analyzing the plurality of candidate bit values to exclude at least one of the candidate bit values for the at least one data bit using information relating to the transmitter; and resolves the at least one data bit based on the analysis.

Claims

1. A method of processing encoded data bits at a receiver, said encoded data bits transmitted from a transmitter to the receiver over a lossy communication channel established over a network, the method comprising:

receiving the encoded data bits over the lossy communication channel, the encoded data bits including redundant data units, at least some original data of the encoded data being lost data during transmission over the lossy communication channel;

receiving transmitter information associated with generation of the received encoded data bits, the transmitter information comprising at least one of;

a source encoder name associated with an encoder used to generate the encoded data bits;

or

a source encoder mode associated with the encoder used to generate the encoded data bits;

decoding the encoded data bits at an error correction decoder;

recovering at least some of the lost data at the error correction decoder based, at least in part, on at least one of the redundant data units;

determining at least one data bit of the lost data is unrecoverable at the error correction decoder based, at least in part, on the error correction decoder finding a plurality of candidate bit values for the at least one unrecoverable data bit;

analyzing the plurality of candidate bit values effective to exclude at least one of the candidate bit values for the at least one unrecoverable data bit based, at least in part, on using the received transmitter information associated with the generation of the encoded data bits to identify a bit value or a sequence of bit values of the plurality of candidate bit values as invalid; and

resolving the at least one unrecoverable data bit based on said analysis.

2. The method according to claim 1, wherein the transmitter information associated with the generation of the received encoded data bits is received over the network.

3. The method according to claim 1 further comprising:

responsive to the error correction decoder finding a plurality of candidate bit values for each data bit in a sequence of data bits, analyzing the plurality of candidate bit values for each bit in the sequence of data bits based, at least in part, on using the transmitter information associated with the generation of the received encoded data bits to determine most likely candidate bit values for the sequence.

4. The method according to claim 1, wherein the transmitter information associated with generation of the received encoded data bits further comprises at least one of:

information on a source of the data bits prior to being encoded;

information on a packetization process used to packetize the encoded data bits; and

information on predetermined rules followed by the transmitter in generating the encoded data bits.

5. The method according to claim 1, wherein the analyzing further comprises identifying if one or more of the plurality of candidate bit values for the at least one data bit will result in a degradation in quality following subsequent decoding of the encoded data bits.

6. The method according to claim 1, wherein the analyzing further comprises:

decoding the candidate bit values using an application decoder to generate a candidate decoded result.

7. The method according to claim 6, the method further comprising:

decoding, using the application decoder, recovered or resolved data bits to generate decoded data bits; and

storing the decoded data bits for use in excluding invalid or low probability candidate decoded results.

8. The method according to claim 6, the method further comprising:

selectively supplying candidate bit values to the application decoder to decode the candidate bit values when candidate bit values cannot be resolved using the transmitter information.

9. The method according to claim 6, wherein the candidate decoded result includes at least one parameter describing an attribute of a frame associated with an original data unit, and wherein the analyzing comprises excluding candidate decoded results representing invalid or low probability values for the at least one parameter based on at least one of knowledge of:

marginal probability distributions of parameter values;

or

correlations between different parameter values.

10. The method according to claim 1, wherein the error correction decoder is associated with decoding a forward error correction (FEC) scheme.

11. The method according to claim 1, wherein the encoded data bits received at the receiver further comprise original data units according to a systematic correction scheme.

12. The method according to claim 11, wherein the encoded data bits include redundant data units which have been generated from the original data units in one of the following ways:

as an exact copy of the original data units;

as a copy of the original data units encoded at the transmitter at a lower bit rate than the original data units;

or

by combining a plurality of original data units.

13. The method according to claim 12, wherein by combining a plurality of original data units, the original data units are combined bit-by-bit using a bitwise XOR operation or byte-by-byte using Galois field GF(2⁸) arithmetic.

14. The method according to claim 1, wherein the redundant data units received at the receiver represent original data and redundant data according to a non-systematic correction scheme.

15. The method according to claim 1, wherein the network is a packet based network.

16. A receiver for processing encoded data bits, the encoded data bits transmitted from a transmitter to the receiver over a lossy communication channel established over a network, the receiver comprising:

a receiving module configured to;

receive the encoded data bits over the lossy communication channel, the encoded data bits including redundant data units, at least some original data of the encoded data being lost data during transmission over the lossy communication channel; and

receive transmitter information associated with generating the encoded data bits, the transmitter information comprising at least one of;

a source encoder name associated with an encoder used to generate the encoded data bits;

or

a source encoder mode associated with the encoder used to generate the encoded data bits;

an error correction decoder configured to;

decode the encoded data bits; and

recover at least some of the lost data bits based, at least in part, on at least one of the redundant data units;

a determining module configured to;

determine when at least one data bit of the lost data is unrecoverable by the error correction decoder due to the error correction decoder finding a plurality of candidate bit values for the at least one unrecoverable data bit;

an analyzer module configured to;

analyze the plurality of candidate bit values effective to exclude at least one of the candidate bit values for the at least one unrecoverable data bit based, at least in part, on using the transmitter information associated with generating the encoded data bits to identify a bit value or a sequence of bit values of the plurality of candidate bit values as invalid; and

a resolving module configured to;

resolve the at least one unrecoverable data bit based on said analysis.

17. The receiver according to claim 16, the receiver further comprising:

an application decoder configured to;

decode recovered or resolved data bits to generate decoded results; and

selectively decode candidate bit values to generate candidate decoded results for use by the analyzer module and the resolving module.

18. The receiver according to claim 17, the receiver further comprising a switching module configured to:

supply the candidate bit values to the application decoder.

19. The receiver according to claim 17, wherein the application decoder comprises:

a voice decoder;

or

a video decoder.

20. A system comprising:

at least one processor; and

one or more computer-readable storage memory devices comprising processor-executable instructions which, responsive to execution by the at least one processor, enable the system to perform a method of processing encoded data bits at a receiver, the encoded data bits transmitted from a transmitter to the receiver over a lossy communication channel established over a network, the method comprising;

receiving the encoded data bits over the lossy communication channel, the encoded data bits contained in packets, the encoded data bits comprising redundant data units, at least some original data of the encoded data in the packets being lost packets during transmission over the lossy communication channel;

receiving transmitter information associated with the transmitter that generated the encoded data bits, the transmitter information comprising at least one of;

a source encoder name associated with an encoder used to generate the encoded data bits,

a source encoder mode associated with the encoder used to generate the encoded data bits;

decoding the encoded data bits at an error correction decoder;

recovering at least some of the lost packets at the error correction decoder based, at least in part, on at least one of the redundant data units and at least one other packet;

determining at least one lost packet is unrecoverable by the error correction decoder due to the error correction decoder finding a plurality of candidate bit values for at least one data bit in the at least one lost packet;

analyzing the plurality of candidate bit values effective to exclude at least one of the candidate bit values for the at least one unrecoverable data bit based, at least in part, on using the transmitter information to identify a bit value or a sequence of bit values of the plurality of candidate bit values as invalid; and

resolving the at least one unrecoverable data bit of the at least one lost packet based on said analysis.