Error resilient scalable audio coding

1. A scalable audio coding apparatus comprising:

a signal processor for signal-processing input audio signals;

a quantizer for quantizing the signal processed input audio signals into quantized data of weighted subbands; and

an encoder for bit-plane coding the quantized data into an embedded audio bitstream of bit-planes, wherein:

the embedded audio bitstream includes binary data having bits;

each said bit-plane has a data unit that includes:

a beginning partition having one or more contiguous refinement bits;

a second partition having one or more contiguous coded significance bits;

a third partition having one or more contiguous sign boundary mark bits; and

a fourth partition having one or more contiguous coded sign bits;

the third partition is between the second and fourth partitions.

2. The scalable audio coding apparatus as defined in claim 1 , wherein each said data unit further comprises a last partition having dummy zeros, whereby the data unit is byte-aligned.

3. The scalable audio coding apparatus as defined in claim 1 , wherein:

the quantizer quantizes using a variable length coding algorithm having a finite code;

the bit-plane coding of encoder executes a predetermined coding method; and

the predetermined coding method generates the third partition as an invalid codeword for the predetermined coding method.

4. The scalable audio coding apparatus as defined in claim 3 , wherein the invalid codeword has a significant Hamming distance from valid codewords of the predetermined coding method.

5. A method for scalable audio coding of audio signals, comprising the steps of:

signal-processing input audio signals;

quantizing the signal-processing input audio signals into quantized data of weighted subbands; and

bit-plane coding the quantized data into an embedded audio bitstream of bit planes, wherein:

the embedded audio bitstream includes binary data having bits;

each said bit-plane has a data unit that includes:

a beginning partition having one or more contiguous refinement bits;

a second partition having one or more contiguous coded significance bits;

a third partition having one or more contiguous sign boundary mark bits; and

a fourth partition having one or more contiguous coded sign bits;

the third partition is between the second and fourth partitions.

6. The method as defined in claim 5 , wherein each said data unit further comprises a last partition having dummy zeros, whereby the data unit is byte-aligned.

7. The method as defined in claim 5 , wherein:

said quantizing quantizes using a variable length coding algorithm having a finite code;

the bit-plane coding executes a predetermined coding method; and

the predetermined coding method generates the third partition as an invalid codeword for the predetermined coding method.

8. The method as defined in claim 7 , wherein the invalid codeword has a significant Hamming distance from valid codewords of the predetermined coding method.

9. A computer usable medium having embodied thereon a computer program for coding audio signals into an audio bitstream, the computer program comprising:

a first code segment for signal-processing input audio signals;

a second code segment for quantizing the signal processed input audio signals into quantized data of weighted subbands;

a third code segment to affect bit-plane coding the quantized data into an embedded audio bitstream of bit planes, wherein:

the embedded audio bitstream includes binary data having bits;

each said bit-plane has a data unit that includes:

a beginning partition having one or more contiguous refinement bits;

a second partition having one or more contiguous coded significance bits;

a third partition having one or more contiguous sign boundary mark bits; and

a fourth partition having one or more contiguous coded sign bits;

the third partition is between the second and fourth partitions.

10. The computer program as defined in claim 9 , further comprising:

a fourth code segment to form a last partition of said data having dummy zeros, whereby the data unit is byte-aligned.

11. The computer program as defined in claim 9 , wherein:

the second code segment uses a variable length coding algorithm having a finite code to quantize the signal processed input audio signals into quantized data of weighted subbands;

the third code segment executes a predetermined bit-plane coding method; and

the predetermined bit-plane coding method generates the third partition as an invalid codeword for the predetermined bit-plane coding method.

12. The computer program as defined in claim 11 , wherein the invalid codeword has a significant Hamming distance from valid codewords of the predetermined bit-plane coding method.

13. A scalable audio decoding apparatus comprising:

a decoder to decode an embedded audio bitstream of bit-planes into quantized data of weighted subbands, wherein:

the embedded audio bitstream includes binary data having bits;

each said bit-plane has a data unit that includes:

a beginning partition having one or more contiguous refinement bits;

a second partition having one or more contiguous coded significance bits;

a third partition having one or more contiguous sign boundary mark bits; and

a fourth partition having one or more contiguous coded sign bits;

the third partition is between the second and fourth partitions;

an inverse quantizer to dequantize the quantized data of weighted subbands into audio signals.

14. The scalable audio decoding apparatus as defined in claim 13 , wherein each said data unit further comprises a last partition having dummy zeros, whereby the data unit is byte-aligned.

15. The scalable audio decoding apparatus as defined in claim 13 , wherein the decoder decodes using Reversible exponential Golomb (Exp-Golomb) codewords in a Reversible Variable Length Code (RVLC) algorithm.

16. The scalable audio decoding apparatus as defined in claim 15 , wherein the decoder:

decodes each said second partition having one or more contiguous coded significance bits using Reversible Exp-Golomb codewords that include a variable-length prefix part and a fixed-length suffix part;

performs error detection in the variable-length prefix of the coded significance bits in both forward and backward directions to detect an invalid codeword; and

identifies a location of the invalid codeword upon detection.

17. The scalable audio decoding apparatus as defined in claim 16 , wherein, upon identification of the location of the invalid codeword, the decoder:

compares a result of the error detection in the forward direction with a result of the error detection in the backward direction; and

accepts, for the decoding of the second partition, identical portions of the variable-length prefix of the coded significance bits as determined by the results of the error detection in the forward and backward directions.

18. A method for scalable audio decoding of an embedded audio bitstream into audio signals, comprising the steps of:

decoding an embedded audio bitstream of bit-planes into quantized data of weighted subbands, wherein:

the embedded audio bitstream includes binary data having bits;

each said bit-plane has a data unit that includes:

a beginning partition having one or more contiguous refinement bits;

a second partition having one or more contiguous coded significance bits;

a third partition having one or more contiguous sign boundary mark bits; and

a fourth partition having one or more contiguous coded sign bits;

the third partition is between the second and fourth partitions;

dequantizing the quantized data of weighted subbands into audio signals.

19. The method as defined in claim 18 , wherein each said data unit further comprises a last partition having dummy zeros, whereby the data unit is byte-aligned.

20. The method as defined in claim 18 , wherein the decoding uses Reversible Exp-Golomb codewords in a RVLC algorithm.

21. The method as defined in claim 20 , wherein the quantizing:

for each of said second partition having one or more contiguous coded significance bits uses Reversible Exp-Golomb codewords that include a variable-length prefix part and a fixed-length suffix part;

performs error detection in the variable-length prefix of the coded significance bits in both forward and backward directions to detect an invalid codeword; and

identifies a location of the invalid codeword upon detection.

22. The method as defined in claim 21 , wherein, upon identification of the location of the invalid codeword, the quantizing:

compares a result of the error detection in the forward direction with a result of the error detection in the backward direction; and

accepts, for the decoding of the second partition, identical portions of the variable-length prefix of the coded significance bits as determined by the results of the error detection in the forward and backward directions.

23. A computer usable medium having embodied thereon a computer program for decoding of an audio bitstream into audio signals, the computer program comprising:

a first code segment to decode an embedded audio bitstream of bit-planes into quantized data of weighted subbands, wherein:

the embedded audio bitstream includes binary data having bits;

each said bit-plane has a data unit that includes:

a beginning partition having one or more contiguous refinement bits;

a second partition having one or more contiguous coded significance bits;

a third partition having one or more contiguous sign boundary mark bits; and

a fourth partition having one or more contiguous coded sign bits;

the third partition is between the second and fourth partitions;

a second code segment to dequantize the quantized data of weighted subbands into audio signals.

24. The computer program as defined in claim 23 , further comprising a fourth code segment to form a last partition of said data unit having dummy zeros, whereby the data unit is byte-aligned.

25. The computer program as defined in claim 23 , wherein the decoding in the first code segment uses Reversible Exp-Golomb codewords in a RVLC algorithm.

26. The computer program as defined in claim 25 , wherein the decoding in the first code segment:

for each of said second partition having one or more contiguous coded significance bits, uses Reversible Exp-Golomb codewords that include a variable-length prefix part and a fixed-length suffix part;

performs error detection in the variable-length prefix of the coded significance bits in both forward and backward directions to detect an invalid codeword; and

identifies a location of the invalid codeword upon detection.

27. The computer program as defined in claim 26 , wherein, upon identification of the location of the invalid codeword, the quantizing:

compares a result of the error detection in the forward direction with a result of the error detection in the backward direction; and

accepts, for the decoding of the second partition, identical portions of the variable-length prefix of the coded significance bits as determined by the results of the error detection in the forward and backward directions.

28. A data structure for a coded bit-plane of an embedded audio bitstream that includes binary data having bits, the data structure comprising:

a beginning partition having one or more contiguous refinement bits;

a second partition having one or more contiguous coded significance bits;

a third partition having one or more contiguous sign boundary mark bits; and

a fourth partition having one or more contiguous coded sign bits, wherein the third partition is between the second and fourth partitions.

29. The data structure as defined in claim 28 , further comprising one or more zero stuffing bits into an end portion of the data structure, whereby the data structure is aligned with a respective byte.

30. A decoder of a codec that uses the data structure defined in claim 28 to:

decode the embedded audio bitstream of bit-planes into quantized data of weighted subbands; and

dequantize the quantized data of weighted subbands into audio signals.

31. The decoder as defined in claim 30 , wherein the decoder decodes using Reversible Exp-Golomb codewords in a RVLC algorithm.

32. The decoded as defined in claim 31 , wherein the decoder:

decodes each said second partition having one or more contiguous coded significance bits using Reversible Exp-Golomb codewords that include a variable-length prefix part and a fixed-length suffix part;

performs error detection in the variable-length prefix of the coded significance bits in both forward and backward directions to detect an invalid codeword; and

identifies a location of the invalid codeword upon detection.

33. The decoder as defined in claim 32 , wherein, upon identification of the location of the invalid codeword, the decoder:

compares a result of the error detection in the forward direction with a result of the error detection in the backward direction; and

accepts, for the decoding of the second partition, identical portions of the variable-length prefix of the coded significance bits as determined by the results of the error detection in the forward and backward directions.

34. An encoder of a codec that forms the data structure defined in claim 28 by:

signal-processing input audio signals;

quantizing the signal processed input audio signals into quantized data of weighted subbands; and

bit-plane coding the quantized data into an embedded audio bitstream of bit planes.

35. A system comprising:

a client computer coupled to a network; and

a server computer coupled to transmit an embedded audio bitstream of bit-planes to the client computer via the network, wherein the embedded audio bitstreams of bit-planes has a data unit that includes:

a beginning partition having one or more contiguous refinement bits;

a second partition having one or more contiguous coded significance bits;

a third partition having one or more contiguous sign boundary mark bits; and

a fourth partition having one or more contiguous coded sign bits, wherein the third partition is between the second and fourth partitions.

36. The system as defined in claim 35 , wherein client computer comprises a codec including a decoder to:

decode the embedded audio bitstream of bit-planes into quantized data of weighted subbands, and

dequantize the quantized data of weighted subbands into audio signals.

37. The system as defined in claim 36 , wherein when the decoder decoding using Reversible Exp-Golomb codewords in a RVLC algorithm.

38. The systems as defined in claim 37 , wherein the decoder:

decodes the second partition having one or more contiguous coded significance bits using Reversible Exp-Golomb codewords that include a variable-length prefix part and a fixed-length suffix part;

performs error detection in the variable-length prefix of the coded significance bits in both forward and backward directions to detect an invalid codeword; and

identifies a location of the invalid codeword upon detection.

39. The system as defined in claim 38 , wherein, upon identification of the location of the invalid codeword, the decoder:

compares a result of the error detection in the forward direction with a result of the error detection in the backward direction; and

accepts, for the decoding of the second partition, identical portions of the variable-length prefix of the coded significance bits as determined by the results of the error detection in the forward and backward directions.