AUDIO AND SPEECH PROCESSING WITH OPTIMAL BIT-ALLOCATION FOR CONSTANT BIT RATE APPLICATIONS

• US 20110153315A1
• Filed: 02/02/2010
• Published: 06/23/2011
• Est. Priority Date: 12/22/2009
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Fazeldehkordi, Amin, Garudadri, Harinath, Majumdar, Somdeb
• Granted Patent: US 8,781,822 B2
• Time in Patent Office: Days
• US Class Current: 704/203
• CPC Class Codes: G10L 19/002 Dynamic bit allocation for perceptual audio coders G10L19/032
• CPC Class Codes: G10L 19/0212 using orthogonal transformation
• CPC Class Codes: G10L 19/035 Scalar quantisation

Abstract

Methods and apparatus for audio and speech processing including generating a plurality of frames, each of the frames comprising a plurality of transform coefficients, and allocating bits to the transform coefficients in each of the frames such that at least two of the transform coefficients in the same frame have different bit allocations and the total number of the bits allocated to the transform coefficients in at least two of the frames is equal.

Claims

1. A method of audio or speech processing, comprising:

generating a plurality of frames, each of the frames comprising a plurality of transform coefficients; and

allocating bits to the transform coefficients in each of the frames such that at least two of the transform coefficients in the same frame have different bit allocations and the total number of the bits allocated to the transform coefficients in at least two of the frames is equal.

2. The method of claim 1 wherein the allocation of the bits is based on a dictionary comprising a plurality of bit allocation vectors.

3. The method of claim 2 wherein each of the bit allocation vectors comprises a plurality of elements, each of the elements representing a possible bit allocation for a corresponding one of the transform coefficients in any one of the frames, wherein the sum of the elements of all bit allocation vectors in the dictionary equals a fixed number.

4. The method of claim 2 wherein the allocation comprises selecting one of the bit allocation vectors from the dictionary for each of the frames.

5. The method of claim 4 wherein the allocation comprises quantizing the transform coefficients for each of the frames based on the selected bit allocation vector for that frame.

6. The method of claim 4 wherein the selection comprises computing a metric based on a magnitude of at least one of the transform coefficients for that frame, and selecting the bit allocation vector based on the metric.

7. The method of claim 4 wherein each of the bit allocation vectors is identified by an index, the method further comprising transmitting each of the frames with the index for the bit allocation vector selected for that frame.

8. The method of claim 7 wherein the index for each of the frames is transmitted within that frame.

9. The method of claim 7 wherein the index for each of the frames is transmitted independent of the transmission of that frame.

10. The method of claim 2 wherein the allocation comprises selecting one of the bit allocation vectors from the dictionary for at least two of the frames.

11. The method of claim 10 wherein the selection comprises computing a metric based on a magnitude of at least one of the transform coefficients for said at least two of the frames, and selecting the bit allocation vector based on the metric.

12. The method of claim 10 wherein the allocation further comprises quantizing the transform coefficients for each of said at least two of the frames based on the selected bit allocation vector.

13. The method of claim 10 wherein each of the bit allocation vectors is identified by an index, the method further comprising transmitting said at least two of the frames with the index for the bit allocation vector.

14. An apparatus for audio or speech processing, comprising:

a processing system configured to;

generate a plurality of frames, each of the frames comprising a plurality of transform coefficients; and

allocate bits to the transform coefficients in each of the frames such that at least two of the transform coefficients in the same frame have different bit allocations and the total number of the bits allocated to the transform coefficients in at least two of the frames is equal.

15. The apparatus of claim 14 wherein the processing system further comprises a dictionary having a plurality of bit allocation vectors, and wherein the processing system is further configured to allocate the bits based on the dictionary.

16. The apparatus of claim 15 wherein each of the bit allocation vectors comprises a plurality of elements, each of the elements representing a possible bit allocation for a corresponding one of the transform coefficients in any one of the frames, wherein the sum of the elements of all the bit allocation vectors in the dictionary equals a fixed number.

17. The apparatus of claim 15 wherein the processing system is further configured to allocate bits by selecting one of the bit allocation vectors from the dictionary for each of the frames.

18. The apparatus of claim 17 wherein the processing system is further configured to allocate bits by quantizing the transform coefficients for each of the frames based on the selected bit allocation vector for that frame.

19. The apparatus of claim 17 wherein the processing system is further configured to select one of the bit allocation vectors by computing a metric based on a magnitude of at least one of the transform coefficients for that frame, and selecting the bit allocation vector based on the metric.

20. The apparatus of claim 17 wherein each of the bit allocation vectors is identified by an index, and wherein the apparatus further comprises a transmitter configured to transmit each of the frames with the index for the bit allocation vector selected for that frame.

21. The apparatus of claim 20 wherein the transmitter is configured to transmit the index for each of the frames within that frame.

22. The apparatus of claim 20 wherein the transmitter is configured to transmit the index for each of the frames independent of the transmission of that frame.

23. The apparatus of claim 15 wherein the processing system is further configured to allocate bits by selecting one of the bit allocation vectors from the dictionary for at least two of the frames.

24. The apparatus of claim 23 wherein the processing system is further configured to select the bit allocation vector by computing a metric based on a magnitude of at least one of the transform coefficients for said at least two of the frames, and selecting the bit allocation vector based on the metric.

25. The apparatus of claim 23 wherein the processing system is further configured to allocate bits by quantizing the transform coefficients for each of said at least two of the frames based on the selected bit allocation vector.

26. The apparatus of claim 23 wherein each of the bit allocation vectors is identified by an index, and wherein the apparatus further comprises a transmitter configured to transmit said at least two of the frames with the index for the bit allocation vector selected for said at least two of the frames.

27. An apparatus for audio or speech processing, comprising:

means for generating a plurality of frames, each of the frames comprising a plurality of transform coefficients; and

means for allocating bits to the transform coefficients in each of the frames such that at least two of the transform coefficients in the same frame have different bit allocations and the total number of the bits allocated to the transform coefficients in at least two of the frames is equal.

28. The apparatus of claim 27 wherein the means for allocating bits comprises means for allocating the bits based on a dictionary comprising a plurality of bit allocation vectors.

29. The apparatus of claim 28 wherein each of the bit allocation vectors comprises a plurality of elements, each of the elements representing a possible bit allocation for a corresponding one of the transform coefficients in any one of the frames, wherein the sum of the elements of all the bit allocation vectors in the dictionary equals a fixed number.

30. The apparatus of claim 28 wherein the means for allocating bits comprises means for selecting one of the bit allocation vectors from the dictionary for each of the frames.

31. The apparatus of claim 30 wherein the means for allocation comprises means for quantizing the transform coefficients for each of the frames based on the selected bit allocation vector for that frame.

32. The apparatus of claim 30 wherein the means for selecting comprises means for computing a metric based on a magnitude of the transform coefficients for that frame, and means for selecting the bit allocation vector based on the metric.

33. The apparatus of claim 30 wherein each of the bit allocation vectors is identified by an index, the apparatus further comprising means for transmitting each of the frames with the index for the bit allocation vector selected for that frame.

34. The apparatus of claim 33 wherein the means for transmitting comprises means for transmitting the index for each of the frames within that frame.

35. The apparatus of claim 33 wherein the means for transmitting comprises means for transmitting the index for each of the frames independent of the transmission of that frame.

36. The apparatus of claim 28 means for allocating bits comprises further comprises means for selecting one of the bit allocation vectors from the dictionary for at least two of the frames.

37. The apparatus of claim 36 wherein the means for selecting one of the bit allocation vectors comprises means for computing a metric based on a magnitude of at least one of the transform coefficients for said at least two of the frames, and means for selecting the bit allocation vector based on the metric.

38. The apparatus of claim 36 wherein the means for allocating bits further comprises means for quantizing the transform coefficients for each of said at least two of the frames based on the selected bit allocation vector.

39. The apparatus of claim 36 wherein each of the bit allocation vectors is identified by an index, the apparatus further means for transmitting said at least two of the frames with the index for the bit allocation vector selected for said at least two of the frames.

40. A computer-program product for processing audio or speech, comprising:

computer-readable medium encoded with codes executable by a processor to;

generate a plurality of frames, each of the frames comprising a plurality of transform coefficients; and

allocate bits to the transform coefficients in each of the frames such that at least two of the transform coefficients in the same frame have different bit allocations and the total number of the bits allocated to the transform coefficients in at least two of the frames is equal.

41. A headset, comprising:

a transducer;

a processing system configured to;

generate a plurality of frames from audio or speech output from the transducer, each of the frames comprising a plurality of transform coefficients; and

allocate bits to the transform coefficients in each of the frames such that at least two of the transform coefficients in the same frame have different bit allocations and the total number of the bits allocated to the transform coefficients in at least two of the frames is equal; and

a transmitter configured to transmit the frames.

42. A watch comprising:

a user interface;

a processing system configured to;

generate a plurality of frames from audio or speech output from the user interface, each of the frames comprising a plurality of transform coefficients; and

allocate bits to the transform coefficients in each of the frames such that at least two of the transform coefficients in the same frame have different bit allocations and the total number of the bits allocated to the transform coefficients in at least two of the frames is equal; and

a transmitter configured to transmit the frames.

43. A sensing apparatus, comprising:

a sensor;

a processing system configured to;

generate a plurality of frames from audio or speech output from the sensor, each of the frames comprising a plurality of transform coefficients; and

allocate bits to the transform coefficients in each of the frames such that at least two of the transform coefficients in the same frame have different bit allocations and the total number of the bits allocated to the transform coefficients in at least two of the frames is equal; and

a transmitter configured to transmit the frames.