Audio devices with automatic leveling recognition mode

Abstract

This invention provides an active noise reduction (ANR) device and method that offers an enhanced recognition mode function. [Solution] In an ANR audio device including a system for providing an enhanced recognition mode function, the method by the expander 80 includes: acquiring a source audio signal 18 and an ambient noise signal 16; comparing the ambient noise signal with a predefined hearing threshold 84; generating an effective noise signal 86 in response to the comparison; generating an expanded audio signal 38 by selectively adjusting the sound pressure level of the source audio signal based on the effective noise signal; and driving an acoustic transducer of headphones using the expanded audio signal.

Description

[Technical Field]

[0001] Claim of priority This application claims priority to U.S. Provisional Patent Application No. 63 / 286,659, filed on 7 December 2021, and U.S. Patent Application No. 18 / 062,108, filed on 6 December 2022, each of which is incorporated herein by reference in whole.

[0002] This disclosure relates, in general terms, to an active noise reduction (ANR) device that provides enhanced recognition mode functionality. [Background technology]

[0003] Headphones and other acoustic devices may include active noise reduction (ANR) functionality that prevents at least a portion of ambient noise from reaching the user's ears. Thus, ANR devices produce an acoustic isolation effect that at least partially isolates the user from their environment. To mitigate the effects of such isolation, some acoustic devices with ANR functionality may include a "perceptual mode" that sends ambient sounds to the user's ears along with the source audio played on the acoustic device. [Overview of the project]

[0004] All embodiments and features mentioned below can be combined in any technically feasible manner.

[0005] Systems and approaches are disclosed for active noise reduction devices having enhanced recognition mode functionality. Several implementations provide methods that include receiving an ambient noise signal from a microphone associated with a wearable audio device; determining a gain value based on the sound pressure level (SPL) of the ambient noise signal; generating a gain-adjusted ambient noise signal by applying the gain value to the ambient noise signal; generating a total external microphone signal by adding the gain-adjusted ambient noise signal to a noise-reduced ambient signal; generating an augmented audio signal by selectively adjusting a source audio signal based on the gain-adjusted ambient noise signal; and coupling the augmented audio signal with the total external microphone signal and outputting it to an acoustic transducer.

[0006] In additional specific implementation forms, a wearable audio device is provided that includes an acoustic transducer and a microphone and a signal processing system that performs the following operations: receiving an ambient noise signal from a microphone associated with the wearable audio device; determining a gain value based on the sound pressure level of the ambient noise signal; generating a gain-adjusted ambient noise signal by applying the gain value to the ambient noise signal; generating a total external microphone signal by adding the gain-adjusted ambient noise signal to a noise-reduced ambient signal; generating an augmented audio signal by selectively adjusting a source audio signal based on the gain-adjusted ambient noise signal; and coupling the augmented audio signal with the total external microphone signal and outputting it to the acoustic transducer.

[0007] In further implementations, the method includes acquiring a source audio signal and an ambient noise signal; comparing the ambient noise signal with a predefined hearing threshold; generating an effective noise signal in response to the comparison; generating an augmented audio signal by selectively adjusting the sound pressure level of the source audio signal based on the effective noise signal; and using the augmented audio signal to drive the acoustic transducer of headphones.

[0008] Another approach involves a method that includes receiving an ambient noise signal from a microphone associated with a wearable audio device, determining a gain value based on the sound pressure level of the ambient noise signal, generating a gain-adjusted ambient noise signal by applying the gain value to the ambient noise signal, generating a total external microphone signal by adding the gain-adjusted ambient noise signal to a noise-reduced ambient signal, generating an augmented audio signal by selectively adjusting the source audio signal based on a noise control signal, and coupling the augmented audio signal with the total external microphone signal and outputting it to an acoustic transducer.

[0009] The implementation may include one of the following characteristics, or any combination thereof.

[0010] In various implementations, the signal-to-noise ratio (SNR) is determined from the source audio signal and the gain-adjusted ambient noise signal, and generating an augmented audio signal involves selectively adjusting the source audio signal based on the SNR.

[0011] In some cases, generating a noise control signal involves generating a residual sound component based on the SPL of the ambient noise signal and adding the residual sound component to the gain-adjusted ambient noise signal.

[0012] In certain cases, the gain value is determined using a lookup table having an SPL-to-gain value correspondence, the lookup table including a first SPL threshold below which the gain value is set to 1, a second SPL threshold above which the gain value is set to 0, and an SPL range between the first and second SPL thresholds where the gain value fluctuates between 1 and 0.

[0013] In some examples, generating an augmented audio signal involves selectively adjusting the SPL for each of several different frequency bands of the source audio signal.

[0014] In other examples, the method further includes determining the signal-to-noise ratio (SNR) from a source audio signal and a gain-adjusted ambient noise signal, wherein determining the SNR includes determining a sub-SNR for each of the different frequency bands, selectively adjusting the SPL of each different frequency band of the source audio signal based on the associated sub-SNR, and generating an extended audio signal based on the SNR or according to a perceptual masking model. In some embodiments, selectively adjusting the SPL of each different frequency band of the source audio signal is based on the associated sub-SNR combined with the sub-SNR for lower frequency bands in a weighted manner.

[0015] In some examples, the different frequency bands of an audio signal include low-frequency bands, mid-frequency bands, and high-frequency bands.

[0016] In some embodiments, the SPL in the low-frequency band is increased in response to the SNR satisfying a first threshold. The SPL in the low-frequency and mid-frequency bands is increased in response to the SNR satisfying a second threshold, and the SPL in the low-frequency, mid-frequency, and high-frequency bands is increased in response to the SNR satisfying a third threshold, where the third threshold is greater than the second threshold, and the second threshold is greater than the first threshold.

[0017] In certain embodiments, comparing an ambient noise signal to a hearing threshold involves comparing the energy levels from each of a predefined set of frequency bands between the ambient noise signal and the hearing threshold.

[0018] In other cases, generating an effective noise signal involves determining the maximum value between the ambient noise signal and the hearing threshold for each of the different frequency bands of a predefined set of frequency bands, and providing an effective noise signal using the maximum value for each of the predefined set of frequency bands.

[0019] Two or more features described in this disclosure that include the features described in the Summary section may be combined to form implementations not specifically described herein.

[0020] Details of one or more implementations are described in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims.

Brief Description of the Drawings

[0021] [Figure 1] FIG. [FIG. number to be filled in] is a block diagram of a wearable audio device having recognition modes and audio leveling features that provide audio leveling according to various implementations. [Figure 2] FIG. [FIG. number to be filled in] is a block diagram of a recognition mode audio device according to various implementations. [Figure 3] FIG. [FIG. number to be filled in] shows a through - hearing characteristic graph according to various implementations. [Figure 4] FIG. [FIG. number to be filled in] is a block diagram of an expander utilized in a wearable audio device according to various implementations. [Figure 5] FIG. [FIG. number to be filled in] is a block diagram of an enhanced expander utilized in a recognition mode audio device according to various implementations. [Figure 6] FIG. [FIG. number to be filled in] shows an exemplary form factor of a recognition mode audio device according to various implementations.

[0022] Note that the drawings of the various implementations are not necessarily to scale. The drawings are intended to show only typical aspects of the disclosure and thus should not be regarded as limiting the scope of the implementations. In the drawings, like numerals represent like elements between the drawings.

Modes for Carrying Out the Invention

[0023] Various implementations enable the use of active noise reduction (ANR) in acoustic devices, while simultaneously describing solutions that allow the user to perceive ambient sounds, referred to herein as “perceptual modes.” Wearable ANR devices, such as ANR headphones, are used to provide a potentially immersive listening experience by reducing the impact of ambient noise and sounds (referred to herein as “ambient noise”) near the user. However, by blocking the impact of ambient noise, ANR devices can create acoustic isolation from the environment, which may be undesirable under certain conditions. For example, a user waiting at an airport may want to perceive flight announcements while using ANR headphones. In another example, a user may want to use ANR headphones to counteract cabin noise during flight, while still being able to communicate with cabin crew without having to remove the headphones.

[0024] Recognition mode audio devices face various technical challenges, including the fact that the type and amount of ambient noise can change while the device is in use. To provide a balanced user experience, the amount of noise reduction may need to be increased or decreased to maintain ambient noise at a desired level. In addition, as the ambient noise level increases, the source audio content may need to be boosted to compensate for the excessive ambient noise reaching the user's ears. The approach described herein addresses these and other technical challenges by providing a recognition mode auto-leveler that automatically adjusts both the amount of noise cancellation and the amount of boost to provide a balanced user experience.

[0025] It is understood that the solutions disclosed herein are intended to be applicable to a wide variety of ANR-based wearable audio devices, i.e., devices that are at least partially worn by a user near at least one of the user's ears and are structured to provide ANR functionality to at least one ear. ANR processing may include either or both feedback-based ANR and feedforward-based ANR. Exemplary wearable audio devices may include headphones, two-way communication headsets, earphones, earbuds, hearing aids, audio glasses, wireless headsets (also known as "earsets"), and ear protectors.

[0026] Furthermore, the solutions disclosed herein are applicable to wearable audio devices that provide two-way audio communication, one-way audio communication (i.e., acoustic output of audio electronically provided by another device), or no communication. Furthermore, what is disclosed herein is applicable to wearable audio devices that are wirelessly connected to other devices, connected to other devices via electrically and / or optically conductive cables, or not connected to any other device. These teachings are applicable to wearable audio devices having physical structures configured to be worn near one or both of the user's ears, including, but not limited to, headphones with one or two earpieces, overhead headphones, behind-the-neck headphones, headsets with communication microphones (e.g., boom microphones), in-ear or behind-the-ear hearing aids, wireless headsets (i.e., earsets), audio glasses, single or pair of earphones, as well as hats, helmets, clothing, or any physical structures that incorporate one or two earpieces to enable audio communication and / or ear protection. The presentation of specific implementations is intended to facilitate understanding through the use of examples and should not be construed as limiting either the scope of the disclosure or the scope of the claims.

[0027] Figure 1 shows an exemplary implementation of an ANR-based audio device ("Audio Device") 10 that provides an automatic leveler for adaptively managing recognition mode functionality. As shown, the Audio Device 10 receives and processes a source audio signal 18 and an ambient noise signal 16. The source audio signal 18 may include any type of audio content, such as streaming music, telephone communications, audio feeds from audiovisual sources, streaming podcasts, audio recordings, etc. The ambient noise signal 16 may include any type of ambient noise, such as an ANR feedforward (i.e., external) microphone, or any other microphone or array of microphones adapted to capture ambient noise near the user. In some implementations, the Audio Device 10 includes (1) a first processing system 12 that adaptively sends some or all of the ambient noise signal 16, which is a resulting signal referred to herein as the "Total External Microphone Signal" 34, and (2) a second processing system 14 that adaptively boosts the source audio signal 18 to generate an augmented noise signal 36. The first processing system 12 and the second processing system 14 work together to adaptively implement an automatic leveler that provides a balanced user experience under changing ambient noise conditions. In the exemplary device 10 shown in Figure 1, the generated total external microphone signal 34, amplified noise signal 36, and feedback back signal 33 (ANR feedback filter K fb The signals (generated by 32 and the associated ANR feedback microphone 31) are coupled and output to the acoustic transducer 20. As a result, the audio device 10 enables the user to achieve a desirable balance of ambient awareness, auditory comfort, and media enjoyment.

[0028] In some exemplary approaches, the first processing system 12 generates a noise reduction ambient signal 17 via a noise reduction path 21 using an ANR filter (K ncThe system includes a 22 and a modulator 24 that generates a gain-adjusted ambient noise signal 25 via a pass-through signal path 23. In some approaches, the amount of gain applied to the ambient noise signal 16 via the pass-through signal path 23 is based on the sound pressure level (SPL) of the ambient noise signal 16. In the illustrated example, the gain-adjusted ambient noise signal 25 is filtered K fb A pass-through filter (K) shapes the external microphone signal to work in conjunction with the feedback-based ANR provided by 32. aw ) is further processed by 26. In some embodiments, K aw 26 equalizes the spectrum of the ambient noise signal 16, for example, so that the signal 16 is not obstructed and sounds natural, as if the user were not wearing a headset. aw 26 also ensures that stability criteria are met for any acoustic path from the driver 20 to the external microphone that receives the ambient noise signal 16.

[0029] The resulting noise-reduced ambient signal 17 and gain-adjusted ambient noise signal 25 are combined to generate a total external microphone signal 34.

[0030] Figure 2 shows an exemplary modulator 24 for generating a gain-adjusted ambient noise signal 25, which includes a variable gain amplifier 48 that adjusts the ambient noise signal 16 based on a calculated gain value 46. In some approaches, the gain value 46 is determined using (1) an energy calculator 40 that measures the SPL of the ambient noise signal 16 using, for example, A weighting; (2) a gain lookup table 42 that determines the gain level based on the corresponding SPL; and (3) a filter 44 that generates the gain value 46 by, for example, smoothing the gain level obtained from the lookup table. The filter 44 controls the trajectory of the gain signal to ensure that the recognition mode signal does not jump rapidly up and down, and allows for smooth changes over a long time constant.

[0031] In some implementations, the modulator 24 can be configured to control the amplifier 48 according to one or more threshold conditions. The threshold conditions can be preset or set according to user input. In some implementations, when the modulator 24 determines that the ambient noise signal 16 is below a certain threshold, the gain value 46 controls the amplifier 48 so that the gain of the pass-through signal path 23 is substantially equal to 1. This allows the user to hear ambient sounds with little or no attenuation. In some implementations, when the modulator 24 determines that the ambient noise signal 16 is above a certain threshold, the gain value 46 can be configured to control the amplifier 48 so that the overall gain of the pass-through signal path 23 is less than 1, and the output of the ANR filter 22 (Figure 1) results in attenuation of the ambient noise signal 16 in the ear. This allows the user to recognize ambient noise and sounds when the noise is below the threshold, but when the noise exceeds the threshold, the ANR function of the device 10 can be used to prevent loud sounds, such as vehicle noise, sirens, or machine noises, from becoming uncomfortably loud.

[0032] FIG. 3 shows an exemplary graph showing the level of the ambient signal 25 gain-adjusted as a function of the ambient noise signal 16. In this case, the gain-adjusted ambient signal 25 is controlled by a modulator 24 that changes the amount of the gain-adjusted ambient signal 25 based on two threshold levels 64, 66 of the ambient noise signal 16. When the ambient noise signal 16 falls below the first threshold 64, the gain-adjusted ambient signal 25 is sent without substantially reducing the ambient noise signal 16 applied thereto (e.g., the gain value is set to 1). When the ambient noise signal 16 exceeds the first threshold 64 but is below the second threshold 66, the gain-adjusted ambient signal 25 is held at a substantially constant level, i.e., as the ambient noise signal 16 increases, the gain is reduced to maintain a substantially constant sound pressure level in the ear (e.g., the gain value varies between 1 and 0). When the ambient noise signal 16 exceeds the second threshold 66, the gain-adjusted ambient signal 25 is set to a minimum (e.g., the gain value is set to 0). Note that in an alternative approach, curve 62 can be achieved with a compressor where the slope between the first threshold 64 and the second threshold 66 can be greater than zero.

[0033] Aspects regarding the first processing system 12 are further described in U.S. Patent Application Publication No. 2019 / 0130928, "Compressive Hear-Through In Personal Acoustic Devices," published on May 2, 2019, which is hereby incorporated by reference in its entirety.

[0034] As described herein, in certain implementations, one objective of the first processing system 12 is to determine the amount of ambient noise to be sent to the listener. In an alternative approach to that described in FIGS. 1 and 2, instead of (or in addition to) controlling the gain value 46 in the pass-through path 23, the amount of noise reduction can be controlled by changing the feedforward filter K nc 22 and / or the feedback filter K fb 32. By thus reducing the noise cancellation signal, K aw26 does not need to overcome all active noise reduction components, but only needs to overcome small passive noise reduction components (multiple components are possible).

[0035] Referring again to Figures 1 and 2, in addition to generating the total external microphone signal 34, the first processing system 12 also outputs a noise control signal 27 to the second processing system 14. In a particular approach, the second processing system 14 automatically adjusts the SPL of the source audio signal 18 to generate an augmented audio signal 36, at least in part, based on a comparison of the SPL of the source audio signal 18 with that of the ambient noise signal 16 (or a signal derived therefrom). In this way, as the ambient noise increases, the audio output of the audio device 10 is automatically adjusted to be louder. If the ambient noise changes to a quieter environment with, for example, a lower SPL, the volume of the audio output is reduced. In various approaches, the noise control signal 27 is used to reflect how much ambient noise is present in the environment and to determine how much SPL augmentation should be applied to the source audio signal 18. In some cases, the second processing system 14 also includes an equalizer (Keq) 28 that first processes the source audio signal 18, for example, adjusting the frequency response so that it hits some target in the ear after being processed by the system.

[0036] In some examples, the noise control signal 27 is based on a gain-adjusted ambient noise signal 25 generated by a modulator 24. In the exemplary modulator 24 shown in Figure 2, the noise control signal 27 is based on the gain-adjusted ambient noise signal 25 and K TIG This is a combination with the residual sound component (RSC) 52 generated by 50. In certain cases, K TIG50 is a filter that attenuates external noise to model the residual sound that reaches the ear even with total ANR. In this case, the gain-adjusted ambient noise signal 25 is 0, and the noise-reduced ambient signal 17 is non-zero. Therefore, the sum, i.e., the total external microphone signal 34, is not 0. Thus, RSC52 provides the SPL received by the ear when the sound is actually loud externally and the total external microphone signal 34 is essentially blocked. In other approaches, instead of being implemented as a filter, K TIG The RSC52 can be provided by simply implementing 50 as a scalar gain.

[0037] Figure 4 shows an exemplary embodiment of an expander 30 in which a signal-to-noise ratio (SNR) calculator 70 is used to generate a sidechain input 74 for controlling an adaptive audio expander 72. In a particular case, the SNR calculator 70 receives both the source audio signal 18 and the noise control signal 27 (which may optionally include at least partially a gain-adjusted ambient noise signal 25), calculates an SNR value, and outputs a sidechain input 74. The sidechain input 74 may consist of the calculated SNR value itself or a value derived from the SNR value. The SNR calculator 70 may include any system for evaluating the source audio signal against the noise signal and outputting a sidechain value 74 which may include, for example, a ratio, a difference, one or more derived values, etc. Nevertheless, the adaptive audio expander 72 uses the sidechain input 74 to control the expansion of the source audio signal 18, i.e., when generating the expanded audio signal 36. In a particular case, the higher the SNR value, the more SPL boost the adaptive audio expander 72 provides.

[0038] In the above implementation, the noise control signal 27 includes, at least partially, a gain-adjusted ambient noise signal 25. In an alternative approach, instead of using the gain-adjusted ambient noise signal 25 to calculate the SNR value (Figure 1), the noise control signal 27 may include calculated values ​​that capture or predict one or more spectral characteristics of the ambient noise signal 16. In specific cases, the SPL or other information derived from the ambient noise signal 16 and / or the total external microphone signal 34 can be analyzed by, for example, a signal processor using a pre-calculated metric table, a machine learning system that evaluates the acoustic environment, etc., to generate one or more spectral characteristic values. The resulting value(s) can then be sent directly to the adaptive audio expander 72, which can use the value(s) to adaptively boost the source audio signal 18. Thus, the noise control signal 27 may include any kind of information or signal that captures, predicts, forecasts, etc., the amount of ambient noise in the environment.

[0039] Depending on the implementation, the amount or type of SPL expansion provided by the expander 30 may be based on several factors. In some cases, the expansion is based on the threshold level of the sidechain input 74. In certain cases, different amounts of boost in SPL are applied to any number of different frequency bands. For example, different boosts are applied to the low (i.e., low frequency), mid (i.e., mid frequency), and / or high (i.e., high frequency) bands. For example, the low frequency band refers to frequencies lower than 100 Hz, the mid frequency band refers to frequencies between 100 Hz and 4 kHz, and the high frequency band refers to frequencies higher than 4 kHz. Depending on the implementation, the SPL boost applied to the low frequency band is greater than the SPL boost applied to the mid frequency band, and the SPL boost applied to the mid frequency band is greater than the SPL boost applied to the high frequency band.

[0040] In some cases, the SPL in the low-frequency band increases in response to the SNR meeting a first threshold. The SPL in the low-frequency and mid-frequency bands increases in response to the SNR meeting a second threshold, and the SPL in the low-frequency, mid-frequency, and high-frequency bands increases in response to the SNR meeting a third threshold, where the third threshold is greater than the second threshold, and the second threshold is greater than the first threshold.

[0041] Table 1 provides exemplary SPL boost values ​​in dB applied to music audio based on frequency range. The music has a constant SPL of 70 dB estimated at the user's ear. Ambient noise (obtained from the noise control signal 27) increases from 50 dB to 65 dB in 5 dB increments. Since there is no or virtually no feedback path, the SPL boost applied for each frequency range does not result in an increase (or substantial increase) in the estimated music SPL at the user's ear. The increase or decrease in SPL is controlled independently for each frequency range. As shown in Table 1, the SPL at low-band frequencies is boosted more than the SPL at mid-band frequencies, and the SPL at mid-band frequencies is boosted more than the SPL at high-band frequencies. Correspondingly, when ambient noise decreases, for example, from 65 dB to 50 dB (i.e., the SNR increases), the SPL at low-band frequencies decreases more than the SPL at mid-band frequencies, and the SPL at mid-band frequencies decreases more than the SPL at high-band frequencies. Furthermore, several limits can be placed on the maximum allowable gain in each band.

[0042] [Table 1]

[0043] In some approaches, the sub-SNR is determined by an SNR calculator 70 for different frequency bands from the ambient noise signal and the gain-adjusted ambient noise signal. For example, the sub-SNR may be determined for low, mid, and high bands to generate three sidechain input values ​​74. The SPL of each different frequency band of the source audio signal 18 is then selectively adjusted by an adaptive audio expander 72 based on the associated sub-SNR.

[0044] Relevant embodiments for implementing the expander are described in U.S. Patent Application Publication No. 2020 / 0143790, “Ambient Volume Control in Open Audio Devices,” published on May 7, 2020, and are incorporated herein by reference in their entirety.

[0045] Referring to Figure 5, an enhancement expander 80 is shown for generating an expanded audio signal 38 from the source audio signal 18. In this approach, an SNR calculator 70 uses an effective noise signal 86 generated by a comparator 82 to determine a sidechain input 74 to the audio expander 72. In this particular approach, the comparator 82 compares the energy level of the ambient noise signal 16 to the audiograph of the user's predefined hearing threshold 84 and uses the two maximum values ​​as the effective noise signal 86. By using a predefined hearing threshold 84, the user hears the content only when the sound is sufficiently loud (i.e., depending on the frequency), and the sound is not masked by noise (again, depending on the frequency). Thus, hearing loss or masking by ambient noise is equivalent, and the same method can be used to ensure that the listener perceives the full spectral sound.

[0046] In some cases, the comparator 82 compares the energy levels of a predefined set or an entire range of frequency bands. In certain cases where predefined frequency bands are compared, the maximum values ​​of each comparison in the predefined set of frequency bands are combined to provide an effective noise signal 86. In other cases where predefined frequency bands are compared, the maximum values ​​of each comparison in the predefined set of frequency bands can be used by the SNR calculator 70 to determine the sub-SNR. The resulting sub-SNR can be used by the audio expander 72 to control the expansion of individual frequency bands. (In various cases, the maximum value is the maximum value of the signal either within a given range or across the entire domain.)

[0047] The enhanced expander 80 may be implemented separately from the first processing system 12 (Figure 1) or integrated with the first processing system 12. When the expander 80 is integrated with the first processing system 12, the ambient noise signal 16 may include a gain-adjusted ambient noise signal 25 or other noise control signals 27 derived from the ambient noise signal 16. When implemented separately, the ambient noise signal 16 may be obtained, for example, from an arbitrary external microphone.

[0048] Device 10, as illustrated and described according to various implementations, should be understood to be structured to be worn by a user to provide audio output near at least one of the user's ears. Device 10 may have one of several form factors, such as a configuration incorporating a single earpiece to provide audio to only one of the user's ears, another configuration incorporating a pair of earpieces to provide audio to both of the user's ears, or another configuration incorporating one or more standalone speakers to provide audio to the environment surrounding the user.

[0049] Figure 6 is a block diagram of one embodiment of an in-ear wearable audio device 100 having two earphones 112A and 112B, each earphone configured to transmit sound to the user's ear. (Reference numbers labeled "A" or "B" indicate that a specific function of one of the two earphones is matched. However, for simplification, the letter designations are omitted from the following description; for example, earpiece 112 refers to either or both earpieces 112A and 112B). Each earpiece 112 includes a case 114 that defines a cavity 116 housing an electroacoustic transducer 128 for outputting an audio signal to the user. In addition, at least one internal microphone 118 is also located within the cavity 116. In an ear-wearable configuration of the wearable audio device 100, an ear coupling 120 (e.g., an ear tip or ear cushion) attached to the case 114 surrounds the opening to the cavity 116. A passage 122 is formed through the ear coupling 120 and communicates with the cavity 116 at its opening. In various configurations, one or more external microphones 124 are positioned on the case in a manner that allows acoustic coupling to the environment outside the case 112.

[0050] The audio output from the converter 128, including both the source audio signal and the total external microphone signal, is implemented by an audio processing system 130 incorporating the first and second processing systems 12, 14 described herein. The audio processing system 130 may be integrated into one or both earpieces 112, or it may be implemented by an external system. If the audio processing system 130 is implemented by an external system, each earpiece 112 may be coupled to the audio processing system 130 in either a wired or wireless configuration. In various implementations, the audio processing system 130 may include hardware, firmware, and / or software to provide various features to support the operation of the wearable audio device 100, including, for example, power supply, amplification, input / output, network interface, user control functions, ANR, signal processing, data storage, data processing, voice detection, etc.

[0051] In implementations that include ANR for enhancing audio signals, the inner microphone 118 may function as a feedback microphone and the outer microphone 124 may function as a feedforward microphone. In such implementations, each earphone 112 may utilize an ANR circuit that communicates with the inner microphone 118 and the outer microphone 124. The ANR circuit receives an internal signal generated by the inner microphone 118 and an external signal generated by the outer microphone 124 and performs ANR processing on the corresponding earphone 112. This process includes supplying a signal to an electroacoustic transducer (e.g., a speaker) 128 located within the cavity 116 to generate a noise reduction acoustic signal that reduces sound from one or more acoustic noise sources outside the earphone 112, or substantially prevents the sound from being heard by the user.

[0052] It is understood that one or more of the functions of the described system may be implemented as hardware and / or software, and that the various components may include communication paths connecting the components by any conventional means (e.g., wired and / or wireless connections). For example, one or more non-volatile devices (e.g., centralized or distributed devices such as flash memory devices) may store and / or execute programs, algorithms, and / or parameters of the system of one or more described devices. Furthermore, the functionalities or parts thereof described herein, and various modifications thereof (hereinafter "Functions") may be implemented at least in part via computer program products (e.g., computer programs tangibly embodied in information carriers such as one or more non-temporary machine-readable media for execution by the operation of one or more data processing devices (e.g., programmable processors, computers, multiple computers, and / or programmable logical components, etc.) or for controlling the operation thereof).

[0053] Computer programs can be written in any form of programming language, including compiled or interpreted languages, and can be deployed as standalone programs or in any form, including modules, components, subroutines, or other units suitable for use in a computing environment. Computer programs can be deployed to run on one computer or on multiple computers at one location, or they can be distributed across multiple locations and interconnected by a network.

[0054] Actions associated with performing all or part of a function may be performed by one or more programmable processors that execute one or more computer programs to perform the function. All or part of the function may be implemented as a special-purpose logic circuit, such as an FPGA (field programmable gate array) and / or an ASIC (application-specific integrated circuit). Suitable processors for executing computer programs include, by example, both general-purpose microprocessors and special-purpose microprocessors, as well as any one or more processors in any type of digital computer. Generally, a processor may receive instructions and data from read-only memory, random-access memory, or both. The components of a computer include a processor for executing instructions and one or more memory devices for storing instructions and data.

[0055] It should be noted that while the implementations described herein utilize a microphone system to collect input signals, any type of sensor, such as an accelerometer, thermometer, optical sensor, or camera, may be used separately from or in addition to the microphone system to collect input signals.

[0056] Furthermore, any actions associated with implementing all or part of the functions described herein may be performed by one or more networked computing devices. Networked computing devices may be connected via one or more wired and / or wireless networks, such as a local area network (LAN), a wide area network (WAN), a personal area network (PAN), an Internet-connected device, and / or a network, and / or cloud-based computing (e.g., a cloud-based server).

[0057] In various implementations, electronic components described as "connected" can be linked via conventional wired and / or wireless means so that these electronic components can communicate data with one another. Furthermore, subcomponents within a given component can be considered to be linked via conventional paths, although this is not necessarily illustrated.

[0058] Several implementation forms have been described. Nevertheless, additional modifications can be made without departing from the scope of the concept of the present invention as described herein, and it is understood that other implementation forms also fall within the scope of the following claims. [Explanation of symbols]

[0059] 10 devices 12 First Processing System 14. Second Processing System 16. Ambient Noise Signal 17. Noise Reduction Ambient Signals 18 Source audio signal 20 Acoustic transducers 20 drivers 21. Noise Reduction Path 22 ANR Filter 23. Pass-through signal path 24 Modulators 25. Ambient Noise Signal 26. Pass-through filter (Kaw) 27 Noise control signals 28. Equalizer (Keq) 30 Expander 31 ANR Feedback Microphone 33 Feedback back signal 34 Total external microphone signals 36 Extended audio signals 38 Extended audio signals 40 Energy Calculators 42 Gain Lookup Table 44 filters 46. ​​Gain Value 48 Amplifier 52 Residual sound component (RSC) 62 curve 64. First threshold 66. Second threshold 70 SNR Calculator 72 Compatible Audio Expander 74 Sidechain Input 80 Expander 82 Comparator 84 Hearing threshold 86 Effective noise signal 100 In-Ear Wearable Audio Devices 112 earpieces 114 cases 116 Cavity 118 Inside microphone 120 Ear Couplings 122 aisle 124 External microphone 128 Electroacoustic transducer 130 Audio Processing Systems

Claims

1. It is a method, Receiving ambient noise signals from a microphone associated with a wearable audio device, The gain value is determined based on the sound pressure level (SPL) of the ambient noise signal, The gain value is applied to the ambient noise signal to generate a gain-adjusted ambient noise signal, The total external microphone signal is generated by adding the gain-adjusted ambient noise signal to the noise-reduced ambient signal, The process involves generating an extended audio signal by selectively adjusting the source audio signal based on the gain-adjusted ambient noise signal, A method comprising coupling the extended audio signal with the total external microphone signal and outputting it to an acoustic transducer.

2. The method further includes determining the signal-to-noise ratio (SNR) from the source audio signal and the gain-adjusted ambient noise signal. The method according to claim 1, wherein generating the extended audio signal includes selectively adjusting the source audio signal based on the SNR.

3. The method according to claim 1, wherein the source audio signal is adjusted to generate the extended audio signal, and the extension audio signal is based on the coupling of the gain-adjusted ambient noise signal and the residual sound component, wherein the residual sound component is based on the SPL of the ambient noise signal.

4. The aforementioned gain value is determined using a lookup table having a correspondence relationship between SPL and gain value, and the lookup table is A first SPL threshold is set to 1 when the value falls below that, A second SPL threshold, which sets the gain value to 0 when it exceeds that, The method according to claim 1, comprising an SPL range between the first SPL threshold and the second SPL threshold, wherein the gain value varies between 1 and 0.

5. The method according to claim 1, wherein generating the extended audio signal includes selectively adjusting the SPL for each of a plurality of different frequency bands of the source audio signal.

6. The method further includes determining the signal-to-noise ratio (SNR) from the source audio signal and the gain-adjusted ambient noise signal. Determining the SNR includes determining the sub-SNR for each of the different frequency bands. The method according to claim 5, wherein the SPL of each of the different frequency bands of the source audio signal is selectively adjusted based on the associated sub-SNR.

7. The method according to claim 5, wherein the different frequency bands of the audio signal include a low frequency band, a medium frequency band, and a high frequency band.

8. The SPL in the low-frequency band is increased in response to the SNR satisfying a first threshold. The SPL in the low-frequency band and the mid-frequency band is increased in response to the SNR satisfying a second threshold. The SPLs of the low-frequency band, the medium-frequency band, and the high-frequency band are increased in response to the SNR satisfying a third threshold. The third threshold is greater than the second threshold, and the second threshold is greater than the first threshold, The method according to claim 7.

9. It is a wearable audio device, Acoustic transducer and, Microphone and, A signal processing system that performs the following operations, wherein the operations are: Receiving ambient noise signals from a microphone associated with a wearable audio device, The gain value is determined based on the sound pressure level (SPL) of the ambient noise signal, The gain value is applied to the ambient noise signal to generate a gain-adjusted ambient noise signal, The total external microphone signal is generated by adding the gain-adjusted ambient noise signal to the noise-reduced ambient signal, The process involves generating an extended audio signal by selectively adjusting the source audio signal based on the gain-adjusted ambient noise signal, A wearable audio device comprising a signal processing system that includes coupling the extended audio signal with the total external microphone signal and outputting it to an acoustic transducer.

10. The method further includes determining the signal-to-noise ratio (SNR) from the source audio signal and the gain-adjusted ambient noise signal. The device according to claim 9, wherein generating the extended audio signal includes selectively adjusting the source audio signal based on the SNR.

11. The device according to claim 9, wherein the source audio signal is adjusted to generate the extended audio signal, based on the coupling of the gain-adjusted ambient noise signal and residual sound components, the residual sound components are based on the SPL of the ambient noise signal.

12. The aforementioned gain value is determined using a lookup table having a correspondence relationship between SPL and gain value, and the lookup table is A first SPL threshold is set to 1 when the value falls below that, A second SPL threshold, which sets the gain value to 0 when it exceeds that, The device according to claim 9, comprising an SPL range between the first SPL threshold and the second SPL threshold, wherein the gain value varies between 1 and 0.

13. The method further includes determining the signal-to-noise ratio (SNR) from the source audio signal and the gain-adjusted ambient noise signal. Determining the SNR includes determining the sub-SNR for each of the different frequency bands. The device according to claim 9, wherein the SPL of each of the different frequency bands of the source audio signal is selectively adjusted based on the associated sub-SNR.

14. The audio signal's different frequency bands include a low-frequency band, a medium-frequency band, and a high-frequency band. The SPL in the low-frequency band is increased in response to the SNR satisfying a first threshold. The SPL in the low-frequency band and the mid-frequency band is increased in response to the SNR satisfying a second threshold. The SPLs of the low-frequency band, the medium-frequency band, and the high-frequency band are increased in response to the SNR satisfying a third threshold. The device according to claim 13, wherein the third threshold is greater than the second threshold, and the second threshold is greater than the first threshold.

15. It is a method, To acquire the source audio signal and ambient noise signal, The ambient noise signal is compared with a predetermined hearing threshold, To generate an effective noise signal in response to the above comparison, The process involves generating an extended audio signal by selectively adjusting the sound pressure level of the source audio signal based on the effective noise signal, A method comprising driving the acoustic transducer of headphones using the aforementioned extended audio signal.

16. The system further comprises determining the signal-to-noise ratio (SNR) based on the source audio signal and the effective noise signal. The method according to claim 15, wherein generating the extended audio signal includes selectively adjusting the sound pressure level of the source audio signal based on the SNR.

17. The method according to claim 16, wherein comparing the ambient noise signal with the hearing threshold includes comparing the energy levels from each of a predefined set of frequency bands between the ambient noise signal and the hearing threshold.

18. To generate the aforementioned effective noise signal, For each of the different frequency bands of the aforementioned predefined set of frequency bands, the maximum value between the ambient noise signal and the hearing threshold is determined. The method according to claim 17, further comprising using the maximum value of each of the predefined set of frequency bands in order to provide the effective noise signal.

19. The source audio signal includes a low-frequency band, a medium-frequency band, and a high-frequency band. The SPL in the low-frequency band is increased in response to the SNR satisfying a first threshold. The SPL in the low-frequency band and the mid-frequency band is increased in response to the SNR satisfying a second threshold. The SPLs of the low-frequency band, the medium-frequency band, and the high-frequency band are increased in response to the SNR satisfying a third threshold. The method according to claim 16, wherein the third threshold is greater than the second threshold, and the second threshold is greater than the first threshold.

20. To generate the aforementioned extended audio signal, Determining the sub-signal-to-noise ratio (sub-SNR) for each different frequency band for the source audio signal and the effective noise signal, The method according to claim 15, further comprising selectively increasing the sound pressure level (SPL) of different frequency bands of the audio signal based on the sub-SNR.

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