Dual-microphone camera

Patent metadata

Field	Value
Publication number	US-9635257-B2
Application number	US-201414275696-A
Country	US
Kind code	B2
Filing date	May 12, 2014
Priority date	May 12, 2014
Publication date	Apr 25, 2017
Grant date	Apr 25, 2017

Abstract

A camera is configured with multiple microphones to reduce wind noise in audio data collected by the camera. The camera receives motion data, which may comprise data indicating acceleration of the camera, a plurality of video frames received by the camera, or a background level of noise associated with one or more microphones configured on the camera. The camera determines a motion vector from the motion data. The motion vector is parallel to the direction of motion of the camera. The camera selects a subset of one or more microphones in the direction of the motion vector. By recording audio data using the one or more selected microphones, the camera reduces wind noise in the audio data.

First claim

What is claimed is:

1. A method for activating at least one of a plurality of microphones configured within a camera, comprising;
receiving motion data from a camera accelerometer, the motion data representative the camera's movement;
determining a motion vector for the camera based on the received motion data, the motion vector based on a direction in which the camera is moving;
selecting less than all of the plurality of microphones based on the motion vector, wherein each selected microphone is located on a camera surface facing the direction of the motion vector; and
capturing audio data using only the selected microphones and not the unselected microphones in the plurality of microphones such that the unselected microphones do not produce audio signals.

2. The method of claim 1 , wherein motion data is received while the camera is receiving video data.

3. The method of claim 1 , further comprising:
integrating the motion data to determine the velocity of the camera; and
determining the motion vector for the camera based on the integrated motion data.

4. The method of claim 1 , wherein selecting less than all of the plurality of microphones comprises:
for each camera surface including a microphone, determining an associated surface vector, the surface vector comprising a vector perpendicular to the camera surface;
identifying a subset of the surface vectors, the angular displacement between each identified surface vector in the subset of surface vectors and the motion vector comprising an angle less than 90 degrees; and
selecting the less than all of the plurality of microphones based on the identified subset of surface vectors, the selected microphones located on camera surfaces associated with surface vectors in the identified subset of surface vectors.

5. The method of claim 4 , wherein the camera selects the microphone associated with the surface vector with the smallest angular displacement from the motion vector.

6. The method of claim 4 , wherein the camera selects the microphone associated with the surface vector with a largest angular displacement from the motion vector.

7. The method of claim 1 , wherein the motion vector is equal in direction and magnitude to the camera's velocity.

8. A method for activating at least one of a plurality of microphones configured within a camera, comprising;
receiving, by the camera, a plurality of video frames;
identifying one or more regions of pixels in the plurality of video frames;
determining a pixel motion vector for each of one or more of the identified regions of pixels, each pixel motion vectors representing the motion of the region of pixels;
determining a motion vector for the camera based on the determined pixel motion vectors, the motion vector based on a direction in which the camera is moving;
selecting less than all of the plurality of microphones based on the motion vector, wherein each selected microphone is located on a camera surface facing the direction of the motion vector; and
capturing audio data using only the selected microphones and not the unselected microphones in the plurality of microphones such that the unselected microphones do not produce audio signals.

9. The method of claim 8 , wherein the motion vector is determined from the pixel motion vector based on an optical flow algorithm.

10. The method of claim 8 , wherein the motion vector is in the direction of the pixel motion vector.

11. The method of claim 8 , wherein selecting less than all of the plurality of microphones comprises:
for each camera surface including a microphone, determining an associated surface vector, the surface vector comprising a vector perpendicular to the camera surface;
identifying a subset of the surface vectors, the angular displacement between each identified surface vector in the subset of surface vectors and the motion vector comprising an angle less than 90 degrees; and
selecting the less than all of the plurality of microphones based on the identified subset of surface vectors, the selected microphones located on camera surfaces associated with surface vectors in the identified subset of surface vectors.

12. The method of claim 11 , wherein selecting less than all of the plurality of microphones comprises selecting a microphone associated with the surface vector with the smallest angular displacement from the motion vector.

13. A method for activating at least one of a plurality of microphones configured within a camera, comprising;
receiving motion data, the motion data describing the motion of the camera;
determining a motion vector for the camera based on the received motion data, the motion vector based on a direction in which the camera is moving;
selecting less than all of the plurality of microphones to activate based on the motion vector; and
capturing audio data using only the selected microphones and not the unselected microphones in the plurality of microphones such that the unselected microphones do not produce audio signals.

14. The method of claim 13 , wherein the motion data comprises a background noise level associated with each microphone configured on the camera.

15. The method of claim 13 , wherein the camera receives the motion data while receiving video data.

16. The method of claim 13 , wherein determining the motion vector for the camera further comprises:
determining the microphone associated with the lowest level of background noise; and
determining the motion vector as the vector in the direction of the vector normal to the camera surface including the microphone associated with the lowest level of background noise.

17. The method of claim 13 , wherein selecting less than all of the plurality of microphones comprises: for each camera surface including a microphone, determining an associated surface vector, the surface vector comprising a vector perpendicular to the camera surface;
identifying a subset of the surface vectors, the angular displacement between each identified surface vector in the subset of surface vectors and the motion vector comprising an angle less than 90 degrees; and
selecting the less than all of the plurality of microphones based on the identified subset of surface vectors, the selected one or more microphones located on camera surfaces associated with surface vectors in the identified subset of surface vectors.

18. The method of claim 17 , wherein selecting less than all of the plurality of microphones comprises selecting a microphone associated with the surface vector with the smallest angular displacement from the motion vector.

19. A camera, comprising:
a plurality of microphones located on one or more surfaces of the camera;
a processor configured to:
receive motion data, the motion data describing a motion of the camera,
determine a motion vector for the camera based on the received motion data, the motion vector representative of a direction in which the camera is moving, and
select less than all of the plurality of microphones to activate based on the motion vector; and

a microphone controller configured to activate only the selected microphones for capturing audio data and not the unselected microphones in the plurality of microphones such that the unselected microphones do not produce audio signals.

20. The camera of claim 19 , wherein the motion data is determined based on a background noise level associated with each of the plurality of microphones.

21. The camera of claim 19 , wherein the motion data is received while receiving v

Assignees

• Gopro Inc

Inventors

• Tisch Erich
• Barbier Fabrice
• Campbell Scott Patrick

Classifications

• H04N23/6811

  based on the image signal · CPC title

• H04N23/6812 Primary

  based on additional sensors, e.g. acceleration sensors · CPC title

• G06T7/20 Primary

  Analysis of motion (motion estimation for coding, decoding, compressing or decompressing digital video signals H04N19/43, H04N19/51) · CPC title

• H04N2101/00

  Still video cameras · CPC title

• H04R2410/07

  Mechanical or electrical reduction of wind noise generated by wind passing a microphone · CPC title