ACTIVE NOISE CONTROL AND CUSTOMIZED AUDIO SYSTEM

Abstract

An audio customization system responsive to one or more inputs that enhance aspects of an audio output and one or more inputs that diminish aspects of an audio output. The system is set up to be able to lessen the influence of ambient audio or in some situations enhance ambient audio over source audio. The system may specify aspects of audio to be modified by specification of filtering algorithm, characterization of audio samples, monitored distortion, user selection, location specification or environmental specification.

Claims

1. An audio customization system comprising: an adaptive filter having a source audio input and an audio signal output; a filtration control connected to said adaptive filter; a variable input control connected to said filtration control wherein said variable input control dynamically influences said filtration control; wherein said variable input control further comprises a database containing adaptive filter parameters indexed according to non-audio parameters; and a non-audio monitor connected to said database.

2. An audio customization system according to claim 1 wherein said variable input control further comprises a user control.

3. An audio customization system according to claim 1 wherein said variable input control further comprises a dynamic audio analysis unit.

4. (canceled)

5. An audio customization system according to claim 1 wherein said identification based variable input is a non-audio environmental identification based variable input control.

6. An audio customization system according to claim 1 wherein said variable input control further comprises a location service based variable input control.

7. (canceled)

8. An audio customization system according to claim 1 wherein said identification based variable input control further comprises an audio based variable input control.

9. An audio customization system according to claim 8 wherein said audio based input control further comprises a database containing adaptive filter parameters indexed according to audio based parameters; and an audio monitor connected to said database.

10. An audio customization system according to claim 1 wherein said non-audio environmental identification-based variable input control further comprises an adaptive filter control responsive to an environmental input.

11. A method for active noise control comprising the steps of: setting a dynamic filtration control input parameter responsive to an audio analysis and a condition identification; establishing an adaptive filter filtration control signal based at least in part on said dynamic filtration control input parameter; and modifying an audio signal to control perceived noise based at least in part on said adaptive filter filtration control signal.

12. (canceled)

13. (canceled)

14. (canceled)

15. An audio customization system according to claim 1 wherein said variable input control further comprises: an adaptive filter parameter control connected to said adaptive filter to enhance an aspect of an audio input.

16. An audio customization system according to claim 15 further comprising an audio sensor array of 3 or more audio sensors connected to said adaptive filter parameter control.

17. An audio customization system according to claim 16 wherein said adaptive filter parameter control is configured to provide directional control in response to said audio sensor array.

18. (canceled)

19. (canceled)

20. A method for controlling an audio filtration process comprising the steps of: setting a filtration exemption control input parameter; establishing an adaptive filter filtration control signal based at least in part on said filtration exemption control input parameter; and modifying an audio signal to attenuate aspects of said audio signal such that a portion of said audio signal corresponding to said filtration exemption control is not excluded by said step of modifying.

21. A method for controlling an audio filtration process according to claim 20 wherein said step of setting a filtration exemption control input parameter is responsive to an audio profile.

22. A method for controlling an audio filtration process according to claim 20 wherein said step of setting a filtration exemption control input parameter is responsive to a voice profile.

23. A method for controlling an audio filtration process according to claim 20 wherein said step of setting a filtration exemption control input parameter is responsive to a frequency parameter to reduce attenuation of aspects of said audio signal corresponding to said frequency parameter.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0091] FIG. 1 shows an embodiment of the invention in the form of an auxiliary box allowing for personal tuning of an active noise reduction system.

[0092] FIG. 2 shows an embodiment of the invention implemented on a personal electronic device, particularly a tablet.

[0093] FIG. 3 shows an embodiment of the invention with two noise-sensing microphones mounted on a set of headphones.

[0094] FIG. 4 shows a schematic of an embodiment of the invention.

[0095] FIG. 5 shows an illustration of an adaptive filter.

[0096] FIG. 6 shows a non-audio based identification input.

[0097] FIG. 7 shows an embodiment of an audio customization system.

[0098] FIG. 8A shows an embodiment of the invention.

[0099] FIG. 8B shows an embodiment of the invention.

[0100] FIG. 8C shows an embodiment of the invention.

[0101] FIG. 8D shows an embodiment of the invention.

[0102] FIG. 8E shows an embodiment of the invention.

[0103] FIG. 9A shows an embodiment of a user control interface.

[0104] FIG. 9B shows an embodiment of a user control interface.

[0105] FIG. 9C shows an embodiment of a user control interface.

[0106] FIG. 9D shows an embodiment of a user control interface.

[0107] FIG. 9E shows an embodiment of a user control interface.

[0108] FIG. 9F shows an embodiment of a user control interface.

[0109] FIG. 9G shows an embodiment of a user control interface.

[0110] FIG. 10 shows a system layout according to an embodiment of the invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0111] Before the present invention is described in further detail, it is to be understood that the invention is not limited to the particular embodiments described, as such may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting, since the scope of the present invention will be limited only by the appended claims.

[0112] Where a range of values is provided, it is understood that each intervening value, to the tenth of the unit of the lower limit unless the context clearly dictates otherwise, between the upper and lower limit of that range and any other stated or intervening value in that stated range is encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included in the smaller ranges is also encompassed within the invention, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included in the invention.

[0113] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the present invention, a limited number of the exemplary methods and materials are described herein.

[0114] It must be noted that as used herein and in the appended claims, the singular forms “a”, “an”, and “the” include plural referents unless the context clearly dictates otherwise.

[0115] All publications mentioned herein are incorporated herein by reference to disclose and describe the methods and/or materials in connection with which the publications are cited. The publications discussed herein are provided solely for their disclosure prior to the filing date of the present application. Nothing herein is to be construed as an admission that the present invention is not entitled to antedate such publication by virtue of prior invention. Further, the dates of publication provided may be different from the actual publication dates, which may need to be independently confirmed.

[0116] FIG. 1 shows a personally tunable custom audio system 101 which may be suitable for Adaptive Noise Cancellation. The system may be implemented in a housing 102. The housing may be portable and have a clip for attaching to a belt, garment or exercise equipment.

[0117] Alternatively, the housing may be integrated with a case for a personal electronic device such as a smartphone or tablet.

[0118] The system may be implemented in a personal electronic device such as a smartphone or tablet.

[0119] The system may have or be connected to a noise-detecting sensor or microphone 110. The sensor may be integrated with the housing or be remote. In the case of a personal electronic device, the system may have a jack 103 for a remote noise-detecting sensor.

[0120] The system may be connected to or integrated with a sound reproduction device such as one or more speakers or headphones. The connection may be by a speaker jack 104.

[0121] The system may be connected to an audio source, for example, a personal media player such as an MP3 player. The connection may use jack 105.

[0122] The system may be provided with an on/off switch 106 and one or more user controls 107. The controls may be for one or more channels such as a left channel tune adjustment 108 and a right channel tune adjustment 109. There may be one or more controls for frequency bands per channel. Alternatively, the controls may be for degree in balance in one or more frequency bands.

[0123] FIG. 2 shows an embodiment implemented on a personal electronic device, 201, such as a tablet or smartphone. The device may have a touch screen 202 and a mechanical control 203. The device shown in FIG. 2 may be implemented in an application. FIG. 2 shows three level sliders 204, 205 and 206 for three frequency bands for the left channel and three level sliders 207, 208 and 209 for three frequency bands for the right channel. There is an on/off switch 210 that is also a touch control. The tablet 201 may have an on-board microphone 211 and a stereo headphone jack 212. Audio input may be provided by an onboard radio player or an external input.

[0124] FIG. 3 shows an embodiment with a housing 301. The housing provided with an input jack 302 which may be connected to an audio source such as an MP3 player 303. The housing 301 is provided with an audio output jack 304. Headphones 305 may be connected by a cable to the jack 304. The housing may be connected to two noise-sensing microphones 307 and 308. The microphones may be hard-wired or connected with a jack.

[0125] The microphones 307 and 308 may be affixed to the headphone earpieces in a manner to approximate location of the user's ears. The housing may also include a left channel control 309, a right channel control 310, and an on/off switch 311.

[0126] According to the invention, the system may be used with or without an audio source. The system may enhance the user's listening experience by reducing the impact of external and ambient noise and sounds when used with an audio source. When used without an audio source, the system still operates to reduce the impact of external sounds and ambient noise.

[0127] FIG. 4 shows a schematic of an embodiment of the custom audio system according to the invention which may be an adaptive noise cancellation system.

[0128] According to an embodiment of the invention, audio is delivered to a user with a perceived reduction of noise. In addition the audio characteristics may be tailored according to a profile selected by a user, a profile determined by audio analysis, a profile indicated by a non-audio input, and/or a preset profile.

[0129] Customized audio according to an embodiment of the invention may be implemented by the use of an adaptive filter. The adaptive filter may be hardware or software implemented. A software implementation may be executed using an appropriate processor and advantageously by a digital signal processor (DSP).

[0130] An adaptive filter is a filter system that has a transfer function controlled by variable parameters. According to embodiments of the invention, an adaptive filter may allow improved control over the adjustment of the parameters.

[0131] User controlled adjustment; audio analysis driven adjustment; and/or non-audio analysis driven adjustment may be used to customize audio input. The adjustment types can be used individually, in combination with each other and/or in combination with other types of adjustment.

[0132] According to an embodiment illustrated in FIG. 4, an adaptive noise cancellation system 401 may receive a source audio signal 402 from an audio source 403 which may provide live or pre-recorded audio. Live audio may be obtained from an audio signal generator or an audio transducer, such as a microphone and analog to digital converter.

[0133] The adaptive noise cancellation system may receive an ambient audio signal 404 from an ambient audio source 405.

[0134] The ambient audio source may include one or more audio transducers such as a microphone(s) for detecting noise. According to one embodiment, two microphones may be used in positions corresponding to a user's ears. According to a different embodiment, a single microphone may be used. The single microphone may be in or connected to the system housing 102, associated with headphones in the form of a headset, or remotely located in a fixed or mobile position.

[0135] Alternatively, the ambient audio source may be an artificial source designed to provide a signal that acts as the base of the cancellation.

[0136] The active noise reduction system has a control unit 406. The control unit 406 provides parameters which define or influence the transfer function.

[0137] FIG. 5 shows a more detailed illustration of the adaptive filter 505 and filter control system 506. The filter control system 506 responds to user variable input parameter control 501, audio analysis based variable control 502, and identification based variable parameter control 503.

[0138] The filtration control unit 504 mixes the variable parameters to create an adaptive filter control signal 507. The adaptive filter control signal defines the transfer function used by the adaptive filter 505.

[0139] User-set variable input parameter controls 501 are useful to tune the transfer function by the user to the preference of the user. The user set variable input parameter controls 501 may be established to permit the user to select a profile for the transfer function. Various profile controls can be provided to the user. For example, a profile specifically tuned to the environment inside of a passenger train. A profile specifically tuned to the environment in a jet airliner, a profile specifically tuned to the environment inside a subway train. The user adjustable controls may be a single control or multiple controls. They may correlate to conventional audio parameters such as bass, treble, frequency response. The user control parameters may be specifically engineered to modify the response of the adaptive filter according to conventional or non-conventional parameters. The user set variable input parameter controls may be controlled through switches and/or knobs on a connected interface or through a software implemented display interface such as a touchscreen. The touchscreen may be on a dedicated interface device or may be implemented in a personal electronic device such as a smart phone.

[0140] Audio analysis based variable controls may be based on a computerized assessment of the ambient audio source signal. The analysis of the ambient source audio may provide input to the filtration control unit 504 to modify the adaptive filter response based on analysis of background noise and/or dominant noise. For example, the audio analysis may assess the background noise typically present on a city street and the result of that analysis is used to influence the filtration control unit 504. The audio analysis may also detect dominant noise, in this example a jackhammer being operated at a construction site, to further influence the filtration control to provide an input to the adaptive filter to compensate for the dominant noise source.

[0141] The identification based variable parameter input unit 503 may provide input to the filtration control unit 504 to influence the response of the adaptive filter 505. Identification based variable parameters are further described in connection with FIG. 6.

[0142] The environmental identification may be provided in the form of a local radio beacon transmitting identification based variables. The local beacon may be transmitting Bluetooth, Wi-Fi or other radio signals. The identification may also be based on location services such as those available in an iOS or Android device. The available variables are provided to the filtration control unit 504 which combines or mixes the signals to generate an adaptive filter control signal 507. The adaptive filter control signal 507 is provided to the adaptive filter 505 and defines the transformation applied to the audio source 403.

[0143] FIG. 6 illustrates identification based adaption non-audio-based variable parameter input unit 503 in order to provide an input to the filtration control unit 504. The identification based variable parameter input unit 503 obtains non-audio environmental identification signals. These non-audio environmental identification signals may serve as an index to noise profile compensation control. The noise profile compensation control may be generic or specific to a particular location. Examples of generic profiles include a passenger train, a bus, a city street, etc. Examples of specific profiles, for example, the main dining in Del Frisco's restaurant in New York City. Or inside of a 1970 Chevelle SS with a well-tuned 396 cubic inch V8 engine.

[0144] FIG. 7 shows an audio customization system. The system includes an audio divider 701. The audio divider has one or more audio inputs 702. The audio inputs may be digital or analog signals. According to the preferred embodiment, analog signals may be digitized using an analog to digital converter. The analog inputs may be connected to microphones, instruments, pre-recorded audio or one or more audio source inputs like a board feed. The audio divider 701 may include one or more demultiplexers in order to separate different audio signals on the same input. The audio divider 701 also includes the capacity to divide input signals into multiple channels, for example, frequency domain channels.

[0145] The audio divider 701 may be implemented in a multi-channel audio processor such as an STA311B available from ST Microelectronics. The STA311B has an automode that may divide an audio signal into eight frequency bands. Audio input signals may be divided, shaped or transferred according to controllable frequency bands or in any other manner that may be accomplished by a digital signal processor or other circuitry. The audio divider may have matrix switching capabilities to allow control of selecting which input(s) is connected to which channel output(s) 703.

[0146] The audio divider 701 may be connected to an audio controller 704 which may dictate the manner in which the audio input signals 702 are handled. Alternatively, the audio divider 701 may be static and transform the audio inputs 702 to channel outputs 703 according to a predefined scheme. In addition the audio divider 701 is connected to a storage unit 705 which may contain pre-recorded audio or audio profiles. The channel outputs 703 of the audio divider 701 are connected to the inputs 706 of an audio processing unit 707. The audio processing unit 707 is responsive to audio controller 704, and contains one or more adaptive filters to combine audio input signals 706. The audio controller 704 dictates which inputs are combined and the manner of combination. The audio processing unit 707 is connected to a mixing unit 708 which combines the channel outputs 703 of the audio processing unit 707 in a manner dictated by audio controller 704. The mixing unit 708 has one or more audio outputs (709). According to one embodiment, the mixing unit 708 may have a two-channel output for connection to a headphone (not shown).

[0147] Mixing may be accomplished using a digital signal processor. For example a Cirrus Logic C54700xx Audio-System-on-a-chip (ASOC) processor may be used to mix the outputs 710 of audio processing unit 707.

[0148] In practical implementation a single digital signal processor may be used to perform the functions of the audio divider 701, audio processing unit 707 and mixing unit 708.

[0149] FIG. 8 shows an illustration of an embodiment of the invention. FIG. 8A shows an integrated input/output headset 801. The headset may include left speaker 802 and right speaker 803. Speakers 802 and 803 may advantageously be connected by a headband 804. A microphone array 805 may be carried on the headband 804 and may include multiple microphones 806. Advantageously, the microphones 806 are directional.

[0150] FIG. 8B shows an alternative embodiment of an input/output unit with microphones 806 located in a neckpiece housing 807 and including earphones 808.

[0151] A third embodiment is illustrated in FIG. 8C. Conventional headphones 810 may be used as an audio output device. A microphone array 809 carrying a plurality of directional microphones 806 may be attached to the headband of a headphone 810.

[0152] FIG. 8D shows an interface with a housing 811 designed to be connected to a belt or other structure by clip 812. The housing 811 may include one or more microphones 806, an input jack 813, and an output jack 814. The input jack 813 may be connected to an audio source such as an mp3 player. The output jack 814 may be connected to speakers, an earphone set or a headphone set.

[0153] A further embodiment shown in FIG. 8E includes a housing 815 configured for connection to a smartphone such as an iPhone or Android phone. The housing 815 may be integrated with or connected to a smartphone case. The device shown in FIG. 8E may include one or more sensor microphones 806. Advantageously, a plurality of directional microphones may be used. Alternatively, one or more omni-directional microphones may be used. The housing 815 may have a connector 816 suitable for electrically connecting the device to a smartphone. In the smartphone embodiment shown in FIG. 8E, the smartphone or other portable electronic device (not shown) may include application software operating as a user control. The signal processing capability may be incorporated into the smartphone or be performed by a separate processor located in the housing.

[0154] In each of the embodiments 8A, 8B, 8C, 8D, and 8E, user controls may be provided for in a connected input/output device such as a smartphone or by controls mounted on any of housings 805, 807, 809, 811 or 815. In addition, an audio divider 702 and mixing unit 708 may be provided for either within the microphone housings or control unit. In addition, connections between the input/output devices, audio inputs, audio processing unit, and mixing unit may be by wired or wireless connections. The same holds true for the controller and audio divider and/or storage if utilized.

[0155] FIG. 9A-G shows alternative aspects of a user control interface for use and connection with the audio optimization system according to the invention.

[0156] FIG. 9A shows a user control interface useful to control noise cancellation according to direction of noise source.

[0157] FIG. 9B shows a user control interface suitable for controlling direction and distance of audio subject to noise cancellation.

[0158] FIG. 9C shows a user control interface to facilitate a user capturing audio to serve as a model for enhancement or cancellation. The interface of FIG. 9B to record a sample audio that is to be exempted from cancellation, enhanced or specifically subject to cancellation. For example a particular ringtone or alarm may be recorded and stored to serve as a profile to permit the same or similar audio to be transferred to the audio output.

[0159] The user control interface may also include controls for channels, volume, bass, treble, midrange, other frequency ranges, selection of cancellation algorithm or profile, selection of enhancement algorithm or profile, feature on/off switches, etc.

[0160] FIG. 9D shows a user control interface including a display of a representation of an ambient sound and sliders to change or customize audible parameters in an audio library.

[0161] FIG. 9E shows a user control interface designed for microphone selection.

[0162] FIG. 9F shows a user control interface including a display allowing selection of distance from ambient sound source and/or microphone array.

[0163] FIG. 9G shows a user control interface including a display corresponding to a noise cancellation algorithm and user input controls.

[0164] FIG. 10 shows a system layout according to an embodiment of the invention. An adaptive noise controller 1001 is provided. The adaptive noise controller 1001 may be connected to a reference microphone array 1002 and to a set of digital filters 1003. The reference microphone array 1002 may also be connected to the digital filters 1003. The digital filters 1003 may rely on ambient sound profiles stored in an ambient sound library 1004 also connected to the adaptive noise controller 1001. A source signal 1005 may be connected to digital filters 1006 which in turn are connected to ambient sound library 1004 and adaptive noise controller 1001. Output devices such as earphone/headphone 1007 may be connected to the adaptive noise controller 1001 and may be connected to a speaker driver 1008. One or more error microphones 1009 may be connected to the adaptive noise controller 1001 and/or the headphone/earphone array 1007.

[0165] The techniques, processes and apparatus described may be utilized to control operation of any device and conserve use of resources based on conditions detected or applicable to the device.

[0166] The invention is described in detail with respect to preferred embodiments, and it will now be apparent from the foregoing to those skilled in the art that changes and modifications may be made without departing from the invention in its broader aspects, and the invention, therefore, as defined in the claims, is intended to cover all such changes and modifications that fall within the true spirit of the invention.

[0167] Thus, specific apparatus for and methods of audio signature generation and automatic content recognition have been disclosed. It should be apparent, however, to those skilled in the art that many more modifications besides those already described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the spirit of the disclosure. Moreover, in interpreting the disclosure, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced.