SIGNALING AUDIO RENDERING INFORMATION IN A BITSTREAM

• US 20140226823A1
• Filed: 02/06/2014
• Published: 08/14/2014
• Est. Priority Date: 02/08/2013
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Sen, Dipanjan, Morrell, Martin James, Peters, Nils Gnther
• Granted Patent: US 10,178,489 B2
• Time in Patent Office: Days
• US Class Current: 381/17
• CPC Class Codes: G10L 19/008 Multichannel audio signal coding or decoding using interchannel correlation to reduce redundancy, e.g. joint-stereo, intensity-coding or matrixing
• CPC Class Codes: G10L 19/167 Audio streaming, i.e. formatting and decoding of an encoded audio signal representation into a data stream for transmission or storage purposes
• CPC Class Codes: H04S 2420/03 Application of parametric coding in stereophonic audio systems
• CPC Class Codes: H04S 2420/11 Application of ambisonics in stereophonic audio systems
• CPC Class Codes: H04S 7/30 Control circuits for electronic adaptation of the sound field
• CPC Class Codes: H04S 7/301 Automatic calibration of stereophonic sound system, e.g. with test microphone
• CPC Class Codes: H04S 7/308 Electronic adaptation dependent on speaker or headphone connection

Abstract

In general, techniques are described for specifying audio rendering information in a bitstream. A device configured to generate the bitstream may perform various aspects of the techniques. The bitstream generation device may comprise one or more processors configured to specify audio rendering information that includes a signal value identifying an audio renderer used when generating the multi-channel audio content. A device configured to render multi-channel audio content from a bitstream may also perform various aspects of the techniques. The rendering device may comprise one or more processors configured to determine audio rendering information that includes a signal value identifying an audio renderer used when generating the multi-channel audio content, and render a plurality of speaker feeds based on the audio rendering information.

Claims

1. A method of generating a bitstream representative of multi-channel audio content, the method comprising:

specifying audio rendering information that includes a signal value identifying an audio renderer used when generating the multi-channel audio content.

2. The method of claim 1, wherein the signal value includes a matrix used to render spherical harmonic coefficients to a plurality of speaker feeds.

3. The method of claim 1, wherein the signal value includes two or more bits that define an index that indicates that the bitstream includes a matrix used to render spherical harmonic coefficients to a plurality of speaker feeds.

4. The method of claim 3, wherein the signal value further includes two or more bits that define a number of rows of the matrix included in the bitstream and two or more bits that define a number of columns of the matrix included in the bitstream.

5. The method of claim 1, wherein the signal value specifies a rendering algorithm used to render audio objects or spherical harmonic coefficients to a plurality of speaker feeds.

6. The method of claim 1, wherein the signal value includes two or more bits that define an index associated with one of a plurality of matrices used to render audio objects or spherical harmonic coefficients to a plurality of speaker feeds.

7. The method of claim 1, wherein the signal value includes two or more bits that define an index associated with one of a plurality of rendering algorithms used to render spherical harmonic coefficients to a plurality of speaker feeds.

8. The method of claim 1, wherein specifying the audio rendering information includes specifying the audio rendering information on a per audio frame basis in the bitstream, a single time in the bitstream or from metadata separate from the bitstream.

9. A device configured to generate a bitstream representative of multi-channel audio content, the device comprising:

one or more processors configured to specify audio rendering information that includes a signal value identifying an audio renderer used when generating the multi-channel audio content.

10. The device of claim 9, wherein the signal value includes a matrix used to render spherical harmonic coefficients to a plurality of speaker feeds.

11. The device of claim 9, wherein the signal value includes two or more bits that define an index that indicates that the bitstream includes a matrix used to render spherical harmonic coefficients to a plurality of speaker feeds.

12. The device of claim 11, wherein the signal value further includes two or more bits that define a number of rows of the matrix included in the bitstream and two or more bits that define a number of columns of the matrix included in the bitstream.

13. The device of claim 9, wherein the signal value specifies a rendering algorithm used to render audio objects or spherical harmonic coefficients to a plurality of speaker feeds.

14. The device of claim 9, wherein the signal value includes two or more bits that define an index associated with one of a plurality of matrices used to render audio objects or spherical harmonic coefficients to a plurality of speaker feeds.

15. The device of claim 9, wherein the signal value includes two or more bits that define an index associated with one of a plurality of rendering algorithms used to render spherical harmonic coefficients to a plurality of speaker feeds.

16. A method of rendering multi-channel audio content from a bitstream, the method comprising:

determining audio rendering information that includes a signal value identifying an audio renderer used when generating the multi-channel audio content; and

rendering a plurality of speaker feeds based on the audio rendering information.

17. The method of claim 16,

wherein the signal value includes a matrix used to render spherical harmonic coefficients to a plurality of speaker feeds, and

wherein rendering the plurality of speaker feeds comprises rendering the plurality of speaker feeds based on the matrix included in the signal value.

18. The method of claim 16,

wherein the signal value includes two or more bits that define an index indicating that the bitstream includes a matrix used to render spherical harmonic coefficients to a plurality of speaker feeds, and

wherein the method further comprises parsing the matrix from the bitstream in response to the index, and

wherein rendering the plurality of speaker feeds comprises rendering the plurality of speaker feeds based on the parsed matrix.

19. The method of claim 18,

wherein the signal value further includes two or more bits that define a number of rows of the matrix included in the bitstream and two or more bits that define a number of columns of the matrix included in the bitstream, and

wherein parsing the matrix from the bitstream comprises parsing the matrix from the bitstream in response to the index and based on the two or more bits that define a number of rows and the two or more bits that define the number of columns.

20. The method of claim 16,

wherein the signal value specifies a rendering algorithm used to render audio objects or spherical harmonic coefficients to the plurality of speaker feeds, and

wherein rendering the plurality of speaker feeds comprises rendering the plurality of speaker feeds from the audio objects or the spherical harmonic coefficients using the specified rendering algorithm.

21. The method of claim 16,

wherein the signal value includes two or more bits that define an index associated with one of a plurality of matrices used to render audio objects or spherical harmonic coefficients to the plurality of speaker feeds, and

wherein rendering the plurality of speaker feeds comprises rendering the plurality of speaker feeds from the audio objects or the spherical harmonic coefficients using the one of the plurality of matrixes associated with the index.

22. The method of claim 16,

wherein the audio rendering information includes two or more bits that define an index associated with one of a plurality of rendering algorithms used to render spherical harmonic coefficients to a plurality of speaker feeds, and

wherein rendering the plurality of speaker feeds comprises rendering the plurality of speaker feeds from the spherical harmonic coefficients using the one of the plurality of rendering algorithms associated with the index.

23. The method of claim 16, wherein determining the audio rendering information includes determining the audio rendering information on a per audio frame basis from the bitstream, a single time form the bitstream or from metadata separate from the bitstream.

24. A device configured to render multi-channel audio content from a bitstream, the device comprising:

one or more processors configured to determine audio rendering information that includes a signal value identifying an audio renderer used when generating the multi-channel audio content, and render a plurality of speaker feeds based on the audio rendering information.

25. The device of claim 24,

wherein the signal value includes a matrix used to render spherical harmonic coefficients to a plurality of speaker feeds, and

wherein the one or more processors are further configured to, when rendering the plurality of speaker feeds, render the plurality of speaker feeds based on the matrix included in the signal value.

26. The device of claim 24,

wherein the signal value includes two or more bits that define an index indicating that the bitstream includes a matrix used to render spherical harmonic coefficients to a plurality of speaker feeds,

wherein the one or more processors are further configured to parse the matrix from the bitstream in response to the index, and

wherein the one or more processors are further configured to, when rendering the plurality of speaker feeds, render the plurality of speaker feeds comprises rendering the plurality of speaker feeds based on the parsed matrix.

27. The device of claim 26,

wherein the signal value further includes two or more bits that define a number of rows of the matrix included in the bitstream and two or more bits that define a number of columns of the matrix included in the bitstream, and

wherein the one or more processors are further configured to, when parsing the matrix from the bitstream, parse the matrix from the bitstream in response to the index and based on the two or more bits that define a number of rows and the two or more bits that define the number of columns.

28. The device of claim 24,

wherein the signal value specifies a rendering algorithm used to render audio objects or spherical harmonic coefficients to the plurality of speaker feeds, and

wherein the one or more processors are further configured to, when rendering the plurality of speaker feeds, render the plurality of speaker feeds comprises rendering the plurality of speaker feeds from the audio objects or the spherical harmonic coefficients using the specified rendering algorithm.

29. The device of claim 24,

wherein the signal value includes two or more bits that define an index associated with one of a plurality of matrices used to render audio objects or spherical harmonic coefficients to the plurality of speaker feeds, and

wherein the one or more processors are further configured to, when rendering the plurality of speaker feeds, render the plurality of speaker feeds comprises rendering the plurality of speaker feeds from the audio objects or the spherical harmonic coefficients using the one of the plurality of matrixes associated with the index.

30. The device of claim 24,

wherein the audio rendering information includes two or more bits that define an index associated with one of a plurality of rendering algorithms used to render spherical harmonic coefficients to a plurality of speaker feeds, and

wherein the one or more processors are further configured to, when rendering the plurality of speaker feeds, render the plurality of speaker feeds comprises rendering the plurality of speaker feeds from the spherical harmonic coefficients using the one of the plurality of rendering algorithms associated with the index.