ENHANCING AUDIO USING A MOBILE DEVICE

• US 20160261247A1
• Filed: 05/17/2016
• Published: 09/08/2016
• Est. Priority Date: 08/01/2013
• Status: Active Grant

• Current Assignee: Caavo Inc
• Original Assignee: Caavo Inc
• Inventors: Aggarwal, Ashish Dharmpal, Satheesh, Sharath Hariharpur
• Granted Patent: US 9,848,263 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 3/165 Management of the audio stream, e.g. setting of volume, audio stream path
• CPC Class Codes: G10L 21/0232 Processing in the frequency domain
• CPC Class Codes: G10L 25/51 for comparison or discrimination
• CPC Class Codes: H03G 3/20 Automatic control H03G3/005 takes precedence; combined with volume compression or expansion H03G7/00
• CPC Class Codes: H03G 3/3005 in amplifiers suitable for low-frequencies, e.g. audio amplifiers H03G3/32, H03G3/34 take precedence
• CPC Class Codes: H03G 3/32 the control being dependent upon ambient noise level or sound level
• CPC Class Codes: H03G 5/005 of digital signals
• CPC Class Codes: H03G 5/165 Equalizers; Volume or gain control in limited frequency bands
• CPC Class Codes: H03G 7/002 in untuned or low-frequency amplifiers, e.g. audio amplifiers H03G7/007, H03G7/001, H03G7/008, H03G7/02, H03G7/06 take precedence
• CPC Class Codes: H03H 17/04 Recursive filters
• CPC Class Codes: H03H 2017/0472 based on allpass structures
• CPC Class Codes: H04R 1/08 Mouthpieces; Microphones; Attachments therefor
• CPC Class Codes: H04R 2430/01 Aspects of volume control, not necessarily automatic, in sound systems
• CPC Class Codes: H04R 2499/11 Transducers incorporated or for use in hand-held devices, e.g. mobile phones, PDA's, camera's
• CPC Class Codes: H04R 25/50 Customised settings for obtaining desired overall acoustical characteristics
• CPC Class Codes: H04R 25/505 using digital signal processing
• CPC Class Codes: H04R 29/00 Monitoring arrangements; Testing arrangements for hearing aids H04R25/30; detection of loudspeaker connection H04R5/04; sound-field adaptation dependent on speaker detection H04S7/308
• CPC Class Codes: H04R 29/001 for loudspeakers H04R29/007 takes precedence
• CPC Class Codes: H04R 29/004 for microphones H04R29/007 takes precedence
• CPC Class Codes: H04R 3/00 Circuits for transducers , loudspeakers or microphones
• CPC Class Codes: H04R 3/04 : for correcting frequency response

Abstract

Embodiments disclosed herein enable detection and improvement of the quality of the audio signal using a mobile device by determining the loss in the audio signal and enhancing audio by streaming the remainder portion of audio. Embodiments disclosed herein enable an improvement in the sound quality rendered by rendering devices by emitting an test audio signal from the source device, measuring the test audio signal using microphones, detecting variation in the frequency response, loudness and timing characteristics using impulse responses and correcting for them. Embodiments disclosed herein also compensate for the noise in the acoustic space by determining the reverberation and ambient noise levels and their frequency characteristics and changing the digital filters and volumes of the source signal to compensate for the varying noise levels.

Claims

1. A method performed by a mobile device for determining an equalizing filter for use in compensating for frequency characteristics of at least one microphone, the method comprising:

communicating a test signal to a source device;

capturing by the at least one microphone a played-back version of the test signal generated by a rendering device coupled to the source device;

determining an impulse response of the captured played-back version of the test signal;

modifying one or more frequency characteristics of the impulse response; and

determining the equalizing filter using the impulse response and the modified frequency characteristics of the impulse response.

2. The method of claim 1, further comprising storing the equalizing filter.

3. The method of claim 2, wherein the storing the equalizing filter comprises storing the equalizing filter in a memory internal to the mobile device.

4. The method of claim 2, wherein the storing the equalizing filter comprises storing the equalizing filter in a memory external to the mobile device.

5. The method of claim 1, wherein the test signal is a logarithmic test sweep signal.

6. The method of claim 1, wherein the modifying the one or more frequency characteristics of the impulse response comprises inverting the one or more frequency characteristics of the impulse response.

7. The method of claim 1, wherein the mobile device and the source device are the same device.

8. A computer program product comprising computer executable program code recorded on a computer readable non-transitory storage medium, said computer executable program code when executed, causing a method for determining an equalizing filter for use in compensating for frequency characteristics of at least one microphone, the method comprising:

communicating a test signal to a source device;

capturing by the at least one microphone a played-back version of the test signal generated by a rendering device coupled to the source device;

determining an impulse response of the captured played-back version of the test signal;

modifying one or more frequency characteristics of the impulse response; and

determining the equalizing filter using the impulse response and the modified frequency characteristics of the impulse response.

9. The computer program product of claim 8, the method further comprising storing the equalizing filter.

10. The computer program product of claim 9, wherein the at least one microphone is included in a mobile device.

11. The computer program product of claim 10, wherein the mobile device and the source device are the same device.

12. The computer program product of claim 8, wherein the test signal is a logarithmic test sweep signal.

13. The computer program product of claim 8, wherein the modifying the one or more frequency characteristics of the impulse response comprises inverting the one or more frequency characteristics of the impulse response.

14. A mobile device configured to determine an equalizing filter for use in compensating for frequency characteristics of at least one microphone of the mobile device, comprising:

a processing unit configured to;

communicate a test signal to a source device;

determine an impulse response of a played-back version of the test signal, the played-back version of the test signal being captured by the at least one microphone, the played-back version of the test signal being generated by a rendering device coupled to the source device;

modify one or more frequency characteristics of the impulse response; and

determine the equalizing filter using the impulse response and the modified frequency characteristics of the impulse response.

15. The mobile device of claim 14, wherein the processing unit is further configured to store the equalizing filter.

16. The mobile device of claim 15, wherein the processing unit is configured to store the equalizing filter in a memory internal to the mobile device.

17. The mobile device of claim 15, wherein the processing unit is configured to store the equalizing filter in a memory external to the mobile device.

18. The mobile device of claim 14, wherein the test signal is a logarithmic test sweep signal.

19. The mobile device of claim 14, wherein the processing unit is configured to modify the one or more frequency characteristics of the impulse response by inverting the one or more frequency characteristics of the impulse response.

20. The mobile device of claim 15, wherein the mobile device and the source device are the same device.