AUTOMATIC AUDIO EQUALIZATION USING HANDHELD MODE DETECTION

• US 20140003626A1
• Filed: 06/28/2012
• Published: 01/02/2014
• Est. Priority Date: 06/28/2012
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: HOLMAN, TOMLINSON M., LINDAHL, ARAM M.
• Granted Patent: US 9,065,410 B2
• Time in Patent Office: Days
• US Class Current: 381/103
• 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: H04R 2499/11 Transducers incorporated or for use in hand-held devices, e.g. mobile phones, PDA's, camera's
• CPC Class Codes: H04S 7/302 Electronic adaptation of stereophonic sound system to listener position or orientation H04S7/301 takes precedence
• CPC Class Codes: H04S 7/307 Frequency adjustment, e.g. tone control H04S7/301 takes precedence

Abstract

A portable audio device that includes a motion sensor, an audio equalizer, a speaker, and a context detector. The motion sensor detects general motion, movement, or acceleration of the device and outputs a series of momentary measurements. The context detector receives these momentary measurements and determines whether the portable audio device is being held in the hand of a user. Upon determining that the device is being held in the hand of user, the audio equalizer performs upward tilt equalization on an audio signal being played by the device through the speaker. Upon determining that the device is not being held in the hand of user (e.g. it is lying flat and still on a surface), the audio equalizer performs downward tilt equalization on the audio signal. Other embodiments are also described.

Claims

1. A method within a portable audio device, comprising:

sampling output data of a motion sensor that is integrated in the portable audio device while the device is outputting an audio signal through an integrated speaker;

determining, based on the sampled output data of the motion sensor, whether the portable audio device is being held;

applying a first audio equalization to the audio signal when the portable audio device is being held; and

applying a second, different audio equalization to the audio signal when the determination is that the portable device is not being held.

2. The method of claim 1, wherein determining whether the portable audio device is being held comprises:

converting the sampled output data of the motion sensor to frequency domain;

detecting a magnitude of a peak in a predetermined frequency range in the frequency domain; and

determining that the portable audio device is being held when the detected magnitude is greater than a predetermined level.

3. The method of claim 1, wherein determining whether the portable audio device is being held is based on the sampled output data of the motion sensor and sample data from an inclinometer separate from the motion sensor.

4. The method of claim 1, wherein the motion sensor is one of an accelerometer and a gyroscope.

5. The method of claim 2, wherein the predetermined frequency range is 10-20 Hz.

6. The method of claim 1, wherein the first audio equalization comprises an upward tilt equalization.

7. The method of claim 6, wherein the second audio equalization comprises a downward tilt equalization.

8. The method of claim 1, wherein the second audio equalization comprises a downward tilt equalization.

9. A method within a portable audio device, comprising:

sampling output data of a motion sensor that is integrated in the portable audio device while the device is outputting an audio signal through an integrated speaker;

determining, based on the sampled output data of the motion sensor, whether the portable audio device is lying still on a fixed surface;

applying a first audio equalization to the audio signal when the portable audio device is lying still on the surface; and

applying a second, different audio equalization to the audio signal when the determination is that the portable device is not lying still on the surface.

10. The method of claim 9, wherein the first audio equalization comprises a downward tilt equalization.

11. The method of claim 10, wherein the second audio equalization comprises an upward tilt equalization.

12. The method of claim 9, wherein the second audio equalization comprises a downward tilt equalization.

13. A portable audio device comprising:

a mobile communications device housing;

a speaker installed in the housing to receive an audio signal;

an audio equalizer to process the audio signal prior to receipt by the speaker;

sensor installed in the housing; and

a context detector installed in the housing and coupled to the motion sensor, the context detector to analyze a sampled data output signal of the motion sensor to detect (a) when the housing is being held, and in response signal the audio equalizer to apply upward tilt audio equalization to the audio signal, and (b) when the device is lying still against a surface and in response signal the audio equalizer to apply downward tilt audio equalization to the audio signal.

14. The portable audio device of claim 13, wherein the context detector is to:

transform the sampled data output signal of the motion sensor to frequency domain,

detect a magnitude of peak in a predetermined frequency range in the frequency domain, and

determine that the portable audio device is being held when the detected magnitude is greater than a predetermined level.

15. The portable audio device of claim 13, wherein the motion sensor is one of an accelerometer and a gyroscope.

16. The portable audio device of claim 13, wherein the audio equalizer is to apply upward tilt audio equalization to the audio signal by one of raising gain at high frequencies relative to low frequencies, and lowering gain at low frequencies relative to high frequencies.

17. The portable audio device of claim 13, wherein the audio equalizer is to apply downward tilt audio equalization to the audio signal by one of raising gain at low frequencies relative to high frequencies, and lowering gain at high frequencies relative to low frequencies.

18. An article of manufacture, comprising:

a machine-readable storage medium that stores instructions which, when executed by a processor in a portable audio device, receive data of a motion sensor while the device is outputting an audio signal through a speaker, analyze the data of the motion sensor to detect that the portable audio device is being held or that the device is lying still and flat against a surface, apply upward tilt audio equalization to the audio signal when the analyzed data indicates the device is being held, and apply downward tilt audio equalization to the audio signal when the analyzed data indicates the device is lying still and flat against the surface.

19. The article of manufacture of claim 18, wherein the storage medium includes further instructions which, when executed by the processor, transform the motion sensor data to frequency domain, detect a magnitude of a peak in a predetermined frequency range in the frequency domain, and determine that the portable audio device is being held when the detected magnitude is greater than a predetermined level.

20. The article of manufacture of claim 18, wherein the motion sensor data is one of accelerometer data and gyroscope data.

21. The article of manufacture of claim 18, wherein the instructions define the upward tilt audio equalization as one of raising gain at high frequencies relative to low frequencies, and lowering gain at low frequencies relative to high frequencies.

22. The article of manufacture of claim 18, wherein the instructions define the downward tilt audio equalization as one of raising gain at low frequencies relative to high frequencies, and lowering gain at high frequencies relative to low frequencies.