Audio Zooming Process within an Audio Scene

• US 20120230512A1
• Filed: 11/30/2009
• Published: 09/13/2012
• Est. Priority Date: 11/30/2009
• Status: Active Grant

• Current Assignee: Nokia Technologies Oy (Nokia Corporation)
• Original Assignee: Nokia Corporation
• Inventors: Ojanperä, Juha
• Granted Patent: US 8,989,401 B2
• Time in Patent Office: Days
• US Class Current: 381/92
• CPC Class Codes: H04R 3/00 Circuits for transducers , loudspeakers or microphones
• CPC Class Codes: H04S 2400/03 Aspects of down-mixing multi-channel audio to configurations with lower numbers of playback channels, e.g. 7.1 -> 5.1 H04S2400/01 takes precedence
• CPC Class Codes: H04S 2400/15 Aspects of sound capture and related signal processing for recording or reproduction
• CPC Class Codes: H04S 7/302 Electronic adaptation of stereophonic sound system to listener position or orientation H04S7/301 takes precedence

Abstract

A method comprising: obtaining a plurality of audio signals originating from a plurality of audio sources in order to create an audio scene; analyzing the audio scene in order to determine zoomable audio points within the audio scene; and providing information regarding the zoomable audio points to a client device for selecting.

Claims

1-30. -30. (canceled)

31. A method comprising:

obtaining a plurality of audio signals originating from a plurality of audio sources in order to create an audio scene;

analyzing the audio scene in order to determine zoomable audio points within the audio scene; and

providing information regarding the zoomable audio points to a client device for selecting.

32. The method according to claim 31, the method further comprising:

in response to receiving information on a selected zoomable audio point from the client device,

providing the client device with an audio signal corresponding to the selected zoomable audio point.

33. The method according to claim 31, wherein the step of analyzing the audio scene further comprises

determining the size of the audio scene;

dividing the audio scene into a plurality of cells;

determining, for the cells comprising at least one audio source, at least one directional vector of an audio source for a frequency band of an input frame;

combining, within each cell, directional vectors of a plurality of frequency bands having deviation angle less than a predetermined limit into one or more combined directional vectors; and

determining intersection points of the combined directional vectors of the audio scene as the zoomable audio points.

34. The method according to claim 33, wherein

the audio scene is divided into the plurality of cells such that each cell comprises at least two audio sources.

35. The method according to claim 33, wherein

the audio scene is divided into the plurality of cells such that the number of audio sources in each cell is within a predetermined limit.

36. The method according to claim 33, wherein prior to determining the at least one directional vector the method further comprises

transforming the plurality of audio signals into frequency domain;

and

dividing the plurality of audio signals in frequency domain into frequency bands complying with equivalent rectangular bandwidth scale.

37. A computer program product, stored on a computer readable medium that when executed causes an apparatus to perform a method according to claim 31.

38. An apparatus comprising at least one processor and at least one memory including computer program, the at least one memory and the computer program configured to, with the at least one processor, cause the apparatus at least to:

obtain a plurality of audio signals originating from a plurality of audio sources in order to create an audio scene;

analyze the audio scene in order to determine zoomable audio points within the audio scene; and

provide information regarding the zoomable audio points to be accessible via a communication interface by a client device.

39. The apparatus according to claim 38, wherein:

in response to receiving information on a selected zoomable audio point from the client device,

the apparatus is arranged to provide the client device with an audio signal corresponding to the selected zoomable audio point.

40. The apparatus according to claim 39, further comprising:

generate a downmixed audio signal corresponding to the selected zoomable audio point.

41. The apparatus according to claim 38, wherein the apparatus is arranged to

determine the size of the audio scene;

divide the audio scene into a plurality of cells;

determine, for the cells comprising at least one audio source, at least one directional vector of an audio source for a frequency band of an input frame;

combine, within each cell, directional vectors of a plurality of frequency bands having deviation angle less than a predetermined limit into one or more combined directional vectors; and

determine intersection points of the combined directional vectors of the audio scene as the zoomable audio points.

42. The apparatus according to claim 41, wherein

the apparatus is arranged to divide the audio scene into the plurality of cells such that each cell comprises at least two audio sources.

43. The apparatus according to claim 41, wherein

the apparatus is arranged to divide the audio scene into the plurality of cells such that the number of audio sources in each cell is within a predetermined limit.

44. The apparatus according to claim 41, wherein

the apparatus is arranged to divide the audio scene into the plurality of cells using a predetermined grid of cells.

45. The apparatus according to claim 41, wherein the apparatus, when determining at least one directional vector, is arranged to

determine input energy for each audio signal for said frequency band of the input frame for a selected time window;

and

determine a direction angle of an audio source on the basis of the input energy of said audio signal relative to a predetermined forward axis of the cell of the audio source.

46. The apparatus according to claim 41, wherein the apparatus, prior to determining the at least one directional vector is arranged to

transform the plurality of audio signals into frequency domain;

and

divide the plurality of audio signals in frequency domain into frequency bands complying with equivalent rectangular bandwidth scale.

47. The apparatus according to claim 38, the apparatus is further arranged to

obtain positioning information of the plurality of audio sources prior to creating the audio scene.

48. A method comprising:

obtaining, in a client device, information regarding zoomable audio points within an audio scene from a server;

representing the zoomable audio points on a display to enable selection of a preferred zoomable audio point; and

in response to obtaining an input regarding a selected zoomable audio point, providing the server with information regarding the selected zoomable audio point.

50. A computer program product, stored on a computer readable medium that when executed causes an apparatus to perform a method according to claim 48.

49. An apparatus comprising at least one processor and at least one memory including computer program, the at least one memory and the computer program configured to, with the at least one processor, cause the apparatus at least to:

obtain information regarding zoomable audio points within an audio scene;

convert the information regarding the zoomable audio points into a form representable on a display to enable selection of a preferred zoomable audio point;

obtain an input regarding a selected zoomable audio point, and

provide information regarding the selected zoomable audio points to be accessible via a communication interface by a server.