TECHNICAL FIELD

The present disclosure relates to the field of voice control technology, and in particular, to a method and a device for processing an audio signal in a vehicle.

BACKGROUND

In the current automobile market, an on-board microphone collects voice only at a fixed position for a main driver in a vehicle, such as a position of a main control console or an overhead light of the vehicle, and is mainly applied to an on-board phone application. In recent years, smart vehicles are increasingly in popularity. Compared with a traditional vehicle, an on-board entertainment system of the smart vehicle is intelligent, networked and personalized in functions, which can obtain multimedia information from the Internet and display them through an on-board large screen.

The existing on-board microphone is generally installed only at a position of an overhead light, a central console or an A pillar of a vehicle, and can only collect sound in a seating area for a driver. This single-zone sound collecting device and its particular position cannot meet a future Internet on-board system, such that an on-board voice recognition system cannot provide service to passengers other than the main driver, let alone provide service to each passenger simultaneously. In addition, the noise reduction effect of the existing microphone is not ideal, and the noise reduction cannot be performed well on some non-human sound (such as sound of opening or closing a vehicle door, engine sound, tire noise and so on). If it is necessary to provide a voice recognition service for each seating area of the whole vehicle, a plurality set of microphone arrays are required to achieve the sound collecting effect in each seating area of the whole vehicle.

SUMMARY

A method and a device for processing an audio signal in a vehicle are provided according to embodiments of the present disclosure, so as to at least solve one or more technical problems in the existing technology.

In a first aspect, a method for processing an audio signal in a vehicle is provided according to an embodiment of the present application, the method includes:

obtaining an audio signal by a microphone array;

performing echo cancellation on the obtained audio signal, to obtain a first processed signal; and

performing beamforming on the first processed signal according to sound zones in which microphones of the microphone array are located, to obtain a second processed signal, wherein the vehicle includes at least two sound zones, and each microphone of the microphone array is located in at least one sound zone.

In one possible implementation, the method further includes:

performing noise reduction and signal amplification on the second processed signal, to obtain a third processed signal, and sending the third processed signal to an on-board operation system of the vehicle, to control the vehicle in response to the third processed signal.

In one possible implementation, the method further includes:

setting the sound zones in which respective microphones of the microphone array is located, based on a topology of the microphone array.

In one possible implementation, the setting the sound zones in which respective microphones of the microphone array is located, based on a topology of the microphone array includes at least one of:

determining a first microphone as a microphone in common with the sound zones, setting a sound zone in which a second microphone is located to a first sound zone, and setting a sound zone in which a third microphone is located to a second zone, wherein the microphone array is a triangle including at least three microphones; and

determining each microphone of the microphone array to be located in at least one sound zone, wherein the microphone array is an N-gon, a circle, or a matrix including a plurality of microphones, and N is an integer greater than 3.

In one possible implementation, the performing beamforming on the first processed signal according to sound zones in which microphones of the microphone array are located, includes:

performing the beamforming on the first processed signal based on the sound zone in which each microphone of the microphone array is located and a time when each microphone receives the audio signal, to determine a sound zone in which a sound source of the audio signal is located.

In one possible implementation, the method further includes:

for each microphone of the microphone array,

determining a location of a sound source of the audio signal received by the microphone, to determine a sound zone in which the sound source is located;

comparing the determined sound zone with the sound zone in which the microphone is located, to determine whether the determined sound zone is identical with the sound zone in which the microphone is located; and

in a case that the determined sound zone is not identical with the sound zone in which the microphone is located, calibrating the sound zone in which the microphone is located by the determined sound zone.

In one possible implementation, the sending the third processed signal to an on-board operation system of the vehicle, includes:

sending the third processed signal to the on-board operation system of the vehicle via an Automotive Audio Bus.

In a second aspect, a device for processing an audio signal in a vehicle is provided according to an embodiment of the present application, the device includes:

a signal obtaining module configured to obtain an audio signal by a microphone array;

an echo cancellation module configured to perform echo cancellation on the obtained audio signal, to obtain a first processed signal; and

a beamforming module configured to perform beamforming on the first processed signal according to sound zones in which microphones of the microphone array are located, to obtain a second processed signal, wherein the vehicle includes at least two sound zones, and each microphone of the microphone array is located in at least one sound zone.

In one possible implementation, the device further includes:

a signal sending module configured to perform noise reduction and signal amplification on the second processed signal, to obtain a third processed signal, and send the third processed signal to an on-board operation system of the vehicle, to control the vehicle in response to the third processed signal.

In one possible implementation, the device further includes:

a sound zone setting module configured to set the sound zones in which respective microphones of the microphone array is located, based on a topology of the microphone array.

In one possible implementation, the sound zone setting module is further configured to set the sound zones in which respective microphones of the microphone array is located based on a topology of the microphone array by at least one of:

determining a first microphone as a microphone in common with the sound zones, setting a sound zone in which a second microphone is located to a first sound zone, and setting a sound zone in which a third microphone is located to a second zone, wherein the microphone array is a triangle including at least three microphones; and

determining each microphone of the microphone array to be located in at least one sound zone, wherein the microphone array is an N-gon, a circle, or a matrix including a plurality of microphones, and N is an integer greater than 3.

In one possible implementation, the beamforming module is further configured to perform the beamforming on the first processed signal based on the sound zone in which each microphone of the microphone array is located and a time when each microphone receives the audio signal, to determine a sound zone in which a sound source of the audio signal is located.

In one possible implementation, the device further includes:

a localizing module configured to, for each microphone of the microphone array, determine a location of a sound source of the audio signal received by the microphone, to determine a sound zone in which the sound source is located;

a comparing module configured to, for each microphone of the microphone array, compare the determined sound zone with the sound zone in which the microphone is located, to determine whether the determined sound zone is identical with the sound zone in which the microphone is located; and

a calibrating module configured to, for each microphone of the microphone array, in a case that the determined sound zone is not identical with the sound zone in which the microphone is located, calibrate the sound zone in which the microphone is located by the determined sound zone.

In one possible implementation, the signal sending module is further configured to send the third processed signal to the on-board operation system of the vehicle via an Automotive Audio Bus.

In a third aspect, an apparatus for processing an audio signal in a vehicle is provided according to an embodiment of the present application. The functions of the apparatus may be implemented by hardware, or by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the above functions.

In a possible design, the structure of the apparatus includes:

a microphone array, configured to collect an audio signal; and

a controller including a processor and a storage, the storage is configured to store a program for supporting the above method for processing an audio signal in a vehicle, executed by the apparatus, the processor is configured to execute the program stored in the storage. The apparatus further includes a communication interface configured for communication between the apparatus and another apparatus or communication network.

In a fourth aspect, a computer-readable storage medium is provided according to an embodiment of the present application, for storing computer software instructions used by the device for processing an audio signal in a vehicle, the computer software instructions include programs involved in execution of the above method for processing an audio signal in a vehicle.

One of the above technical solutions has the following advantages or beneficial effects.

A sound zone in which each microphone in a microphone array is located can be set in advance, so that the beamforming can be performed on an audio signal directly by using the sound zone in which each microphone is located. With such beamforming, the requirements for isolation degree between different sound zones is not high, and a sound source of the audio signal can be accurately determined.

The above summary is for the purpose of the specification only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features of the present application will be readily understood by reference to the drawings and the following detailed description.

