Method and apparatus for recovering burst data loss by duplicating block code symbols

• US 8,819,526 B2
• Filed: 07/08/2011
• Issued: 08/26/2014
• Est. Priority Date: 07/08/2010
• Status: Expired due to Fees

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: Cho, Jai Hyung, Lee, Sang Ho, Suh, Doug Young, Kim, Chul Keun
• Primary Examiner(s): TU, CHRISTINE TRINH LE
• Application Number:
  US13/809,090
• Publication Number:
  US 20130111302A1
• Time in Patent Office: 1,145 Days
• Field of Search: 714/776, 714/751, 714/752, 714/786, 714/787, 714/788, 714/789, 714/814, 714/731
• US Class Current: 714/776
• CPC Class Codes: G06F 11/10 Adding special bits or symbols to the coded information, e.g. parity check, casting out 9's or 11's
• CPC Class Codes: H04L 1/0041 Arrangements at the transmitter end
• CPC Class Codes: H04L 1/0045 Arrangements at the receiver end
• CPC Class Codes: H04L 1/007 Unequal error protection for format H04L1/0078; for codes per se H03M13/35
• CPC Class Codes: H04L 1/0071 Use of interleaving interleaving per se H03M13/27
• CPC Class Codes: H04L 1/008 where the control data relates to payload of a different packet

Abstract

Provided is a method and apparatus for encoding and decoding in which block coding is applied. According to a method and apparatus for block coding encoding and decoding, a minimum quality seamless service may be provided by reliably recovering high importance data even though continuous data loss occurs in a wired and wireless transmission line. A transposed duplication calculation or a post duplication calculation may be performed with respect to the high importance data. Data of a predetermined lost time zone may be recovered by duplicated data of another time zone.

Claims

1. An encoding apparatus comprising:

a low priority buffer;

a high priority buffer;

a priority classifier to receive a data stream in which an importance is indicated, to indicate time information in the data stream, and to classify the data stream into the low priority buffer and the high priority buffer based on the importance and thereby store the data stream; and

a forward error collection (FEC) encoder to perform an encoding calculation for FEC parity data generation by fetching data of the same first time zone from each of the low priority buffer and the high priority buffer to thereby configure a FEC source block, and by fetching, from the high priority buffer, data of a second time zone different from the first time zone to thereby add the fetched data to the FEC source block.

2. The encoding apparatus of claim 1, wherein the second time zone is a time zone ahead of the first time zone by an L time or a time zone behind the first time zone by the L time.

3. The encoding apparatus of claim 2, wherein L corresponds to a maximum length of high importance data to be recovered from continuous burst loss.

4. The encoding apparatus of claim 2, wherein data of the low priority buffer and the high priority buffer is buffered for a minimum of the L time.

5. The encoding apparatus of claim 2, wherein the second time zone is a time zone ahead of the first time zone by the L time and a time zone behind the first time zone by the L time.

6. The encoding apparatus of claim 2, wherein the FEC encoder delays data of the low priority buffer by the L time compared to data of the high priority buffer and thereby transmits the delayed data.

7. The encoding apparatus of claim 6, wherein the FEC encoder sequentially outputs the output data and FEC parity data in which a block identifier is indicated.

8. The encoding apparatus of claim 1, wherein:

the FEC encoder indicates a block identifier in output data constituting a block and FEC parity data, and

data that is duplicated and added to at least two blocks and has a high importance within the high priority buffer is indicated using at least two block identifiers.

9. The encoding apparatus of claim 1, wherein the data stream is a scalable video coding stream, data of the high priority buffer is base frame data, and data of the low priority buffer is enhancement frame data.

10. A decoding apparatus comprising:

a low priority buffer;

a high priority buffer;

a FEC buffer;

a priority classifier to receive FEC data and a data stream in which an importance and a block identifier are indicated, to indicate time information in the data stream and the FEC data, to classify the data stream into the high priority buffer and the low priority buffer and thereby store the data stream, and to store the FEC data in the FEC buffer; and

a FEC decoder to configure a FEC block and perform decoding based on data of the low priority buffer, data of the high priority buffer, and the FEC data,

wherein when lost data of a first time zone is detected, the FEC decoder configures the FEC block by estimating the block identifier to be used for loss recovery using block identifier information of lossless data of the first time zone, by fetching all of lossless data corresponding to the estimated block identifier from the low priority buffer and the high priority buffer, and by fetching all of lossless FEC data corresponding to the estimated block identifier from the FEC buffer, and performs FEC decoding by performing a FEC decoding calculation with respect to the FEC block.

11. The decoding apparatus of claim 10, wherein:

the FEC decoder configures the FEC block by estimating the block identifier of a second time zone different from the first time zone, by fetching all of lossless data corresponding to the estimated block identifier from the low priority buffer and the high priority buffer, and by fetching all of lossless FEC data corresponding to the estimated block identifier from the FEC buffer, and recovers the lost data by performing FEC decoding with respect to the FEC block.

12. The decoding apparatus of claim 11, wherein the second time zone is a time zone ahead of the first time zone by an L time or a time zone behind the first time zone by the L time.

13. The decoding apparatus of claim 12, wherein L corresponds to a maximum length that the decoding apparatus desires to recover high importance data from continuous burst loss.

14. The decoding apparatus of claim 12, wherein:

data of the low priority buffer and the high priority buffer is buffered for at least minimum of the L time, and

the FEC data of the FEC buffer is buffered for the at least minimum of the L time.

15. The decoding apparatus of claim 14, wherein the FEC decoder configures the FEC block by further buffering the data stream and the FEC data for the L time to thereby fetch a block identifier of input data, and by fetching all of lossless data and FEC data corresponding to the fetched block identifier from the low priority buffer, the high priority buffer, and the FEC buffer, and recovers the lost data by performing decoding with respect to the FEC block.

16. The decoding apparatus of claim 12, wherein:

low importance data that is stored in the low priority buffer is delayed by at least the L time compared to high importance data that is stored in the high priority buffer and thereby is transmitted, and

data of the high priority buffer is buffered for at least the L time.

17. The decoding apparatus of claim 11, wherein the second time zone is a time zone ahead of the first time zone by the L time and a time zone behind the first time zone by the L time.

18. An encoding method comprising:

receiving a data stream in which an importance is indicated;

indicating time information in the data stream;

classifying the data stream in which the time information is indicated into a low priority buffer and a high priority buffer based on the importance to thereby store the data stream;

configuring a FEC source block by fetching data of a predetermined time zone from the low priority buffer and the high priority buffer;

fetching, from the high priority buffer, data ahead of or behind the predetermined time zone by an L time to thereby add the fetched data to the FEC source block;

calculating FEC parity data of the FEC source block; and

outputting the FEC source block and the FEC parity data.

19. A decoding method comprising:

receiving FEC data and a data stream in which an importance and a block identifier are indicated;

storing the data stream by classifying the data stream into a low priority buffer and a high priority buffer, and storing the FEC data in a FEC buffer;

configuring a FEC block based on data of the low priority buffer and the high priority buffer and the FEC data;

configuring the FEC block by fetching L-time ahead data or L-time behind data from the low priority buffer, the high priority buffer, and the FEC buffer; and

performing a FEC decoding calculation with respect to the FEC block.