Audio zoom

• US 9,210,503 B2
• Filed: 10/01/2010
• Issued: 12/08/2015
• Est. Priority Date: 12/02/2009
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Audience Corporation
• Inventors: Avendano, Carlos, Solbach, Ludger
• Primary Examiner(s): Lao, Lun-See
• Application Number:
  US12/896,725
• Publication Number:
  US 20110129095A1
• Time in Patent Office: 1,894 Days
• Field of Search: 381/63, 381/92, 381/61, 381 941- 944, 348/14.02
• US Class Current: 1/1
• CPC Class Codes: H04M 1/03 Constructional features of telephone transmitters or receivers, e.g. telephone hand-sets
• CPC Class Codes: H04R 2430/20 Processing of the output signals of the acoustic transducers of an array for obtaining a desired directivity characteristic H04R2203/12 takes precedence
• CPC Class Codes: H04R 2430/21 Direction finding using differential microphone array [DMA]
• CPC Class Codes: H04R 3/005 for combining the signals of two or more microphones specially adapted for hearing aids H04R25/407

Abstract

An audio equivalent of a video zoom feature for video recording and communication applications, as well as video post production processes. The audio zoom may operate in conjunction with a video zoom feature or independently. The audio zoom may be achieved by controlling reverberation effects of a signal, controlling a gain of the signal, as well as controlling the width of a directional beam which is used to select the particular audio component to focus on. The audio zoom may operate in response to user input, such as a user selection of a particular direction, or automatically based a current environment or other factors.

Claims

1. A method for processing a signal, comprising:

receiving one or more acoustic signals captured by two or more microphones on a device;

receiving an indication of a spatial area within an environment, the indication being received from a user of the device;

based on the indication, determining adaptation constraints used to steer a beam, the adaptation constraints including constraints used in an audio noise suppression system;

reducing, using at least one hardware processor, an energy of at least one first acoustic signal component of at least one of the acoustic signals, the at least one acoustic signal being associated with a first source positioned outside the spatial area, the reducing including forming the beam based on the indication, the energy of the at least one first acoustic signal component being reduced for the at least one acoustic signal associated with the first source positioned outside the beam; and

adjusting a reverberation level associated with at least one second acoustic signal component of at least one other of the acoustic signals, the at least one other acoustic signal being associated with a second source positioned inside the spatial area based on the indication.

2. The method of claim 1, wherein forming the beam includes controlling a width of the beam.

3. The method of claim 1, wherein reducing the energy of the at least one first acoustic signal component is performed by subtractive cancellation.

4. The method of claim 1, wherein reducing the energy of the at least one first acoustic signal component is performed by multiplicative expansion or multiplicative cancellation.

5. The method of claim 1, wherein reducing the energy of the at least one first acoustic signal component includes selecting a region based on two or more fixed beam patterns.

6. The method of claim 1, wherein adjusting the reverberation level includes decreasing the reverberation level in response to the indication, the indication being to decrease the spatial area.

7. The method of claim 1, wherein adjusting the reverberation level includes increasing the reverberation level in response to the indication, the indication being to increase the spatial area.

8. The method of claim 1, further comprising applying a gain to the at least one second acoustic signal component of the at least one other acoustic signal, the at least one other acoustic signal being associated with the second source positioned inside the spatial area.

9. The method of claim 1, wherein the receiving of the indication of the spatial area within the environment from the user is by one of a video zoom setting, a pointing of an audio device in a particular direction, and an input for video zoom.

10. The method of claim 8, further comprising:

detecting the second source is inside the spatial area by a null-processing noise subtraction mechanism;

determining energy ratios; and

generating at least one multiplicative mask based on the energy ratios, the at least one multiplicative mask for adjusting the gain for the at least one second acoustic signal component of the at least one other acoustic signal.

11. The method of claim 10, wherein the generating of the at least one multiplicative mask based on the energy ratios comprises:

generating differential areas from the one or more acoustic signals;

generating a beam pattern from the differential areas, the beam pattern being used to determine the energy ratios; and

deriving a filter from the energy ratios.

12. A non-transitory computer readable storage medium having embodied thereon a program, the program being executable by a processor to perform an audio zoom method, the method comprising:

receiving one or more acoustic signals captured by two or more microphones on a device;

receiving an indication of a spatial area within an environment, the indication being received from a user of the device;

based on the indication, determining adaptation constraints used to steer a beam, the adaptation constraints including constraints used in an audio noise suppression system;

reducing an energy of at least one acoustic signal component of at least one of the acoustic signals, the at least one acoustic signal being associated with a first source positioned outside the spatial area, the reducing including forming the beam based on the indication, the energy of the at least one acoustic signal component being reduced for the at least one acoustic signal associated with the first source positioned outside the beam; and

adjusting a reverberation level associated with at least one second acoustic signal component of at least one other of the acoustic signals, the at least one other acoustic signal being associated with a second source positioned inside the spatial area based on the indication.

13. The non-transitory computer readable storage medium of claim 12, wherein forming the beam includes controlling a width of the beam.

14. The non-transitory computer readable storage medium of claim 12, wherein reducing the energy of the at least one first acoustic signal component is performed by subtractive cancellation.

15. The non-transitory computer readable storage medium of claim 12, wherein reducing the energy of the at least one first acoustic signal component is performed by multiplicative expansion or multiplicative cancellation.

16. The non-transitory computer readable storage medium of claim 12, wherein reducing the energy of the at least one first acoustic signal component includes selecting a region based on two or more fixed beam patterns.

17. The non-transitory computer readable storage medium of claim 12, wherein adjusting the reverberation level includes decreasing the reverberation level in response to the indication, the indication being to decrease the spatial area.

18. The non-transitory computer readable storage medium of claim 12, wherein adjusting the reverberation level includes increasing the reverberation level in response to the indication, the indication being to increase the spatial area.

19. A system for performing noise reduction in an audio signal, the system comprising:

a non-transitory memory;

a beamformer module stored in the memory and executed by a processor to identify subband signals associated with an audio source within a spatial area within an environment, the spatial area being indicated by a user input, the user input determining adaptation constraints used to steer a beam, the adaptation constraints including constraints used in an audio noise suppression system, an energy of at least one acoustic signal component of at least one of the acoustic signals being reduced, the at least one acoustic signal being associated with a first source positioned outside the spatial area, the reducing including forming the beam based on the indication, the energy of the at least one acoustic signal component being reduced for the at least one acoustic signal associated with the first source positioned outside the beam; and

a reverb module stored in the memory and executed by a processor to cancel at least a portion of the sub-band signals.