Audio processing system, audio processing device, and audio processing method

1. An audio processing system comprising:

a first microphone that acquires a first audio signal and outputs a first signal based on the first audio signal, the first audio signal including a first audio component originating from a first position and a second audio component originating from a second position different from the first position;

a second microphone that acquires a second audio signal including at least one of the first audio component and the second audio component, outputs a second signal based on the second audio signal, the second microphone being located farther from the first position than the first microphone;

a third microphone that acquires a third audio signal including at least one of the first audio component and the second audio component and outputs a third signal based on the third audio signal, the third microphone being located farther from the second position than the first microphone;

an adaptive filter having a first filter coefficient and a second filter coefficient different from the first filter coefficient, the adaptive filter receives the first signal and outputs a passing signal based on the first signal;

a memory; and

a processor that is coupled to the memory, and, when executing a program stored in the memory:

determines whether the first audio signal includes more of the first audio component or more of the second audio component based on the second signal and the third signal, wherein

when the processor determines that the first audio signal includes more of the first audio component than the second audio component, the adaptive filter outputs the passing signal based on the first signal and the first filter coefficient, and

when the processor determines that the first audio signal includes more of the second audio component than the first audio component, the adaptive filter outputs the passing signal based on the first signal and the second filter coefficient.

2. The audio processing system according to claim 1 , wherein the processor further performs outputting a first directional signal obtained by performing directionality control processing on the second signal and outputting a second directional signal obtained by performing directionality control processing on the third signal.

3. The audio processing system according to claim 2 , wherein the processor determines whether the first audio signal includes more of the first audio component or more of the second audio component based on the first directional signal and the second directional signal.

4. The audio processing system according to claim 2 , wherein

the processor functions as:

a determination unit that makes the determination; and

a directionality control unit that outputs the first directional signal and the second directional signal, and

the directionality control unit includes the determination unit.

5. The audio processing system according to claim 1 , wherein

the first microphone comprises:

a fourth microphone that acquires a fourth audio signal including at least one of the first audio component and the second audio component and outputs a fourth signal based on the fourth audio signal; and

a fifth microphone that acquires a fifth audio signal including at least one of the first audio component and the second audio component, outputs a fifth signal based on the fifth audio signal, and is located closer to the second position than the fourth microphone is,

the processor further performs detecting presence or absence of abnormality of the first microphone, and

the processor performs controlling a filter coefficient of the adaptive filter based on abnormality information on the abnormality of the first microphone and the result of the determination.

6. The audio processing system according to claim 5 , wherein the processor performs

causing a strength of the fourth signal input to the adaptive filter to be zero when detecting abnormality of the fourth microphone, and

causing a strength of the fifth signal input to the adaptive filter to be zero when detecting abnormality of the fifth microphone.

7. The audio processing system according to claim 5 , wherein

the processor functions as:

a determination unit that makes the determination; and

an abnormality detection unit that detects presence or absence of the abnormality and transmits the abnormality information, and

the abnormality detection unit includes the determination unit.

8. An audio processing device comprising:

a memory;

a processor that is coupled to the memory, and, when executing a program stored in the memory, performs receiving a first signal based on a first audio signal including a first audio component originating from a first position and a second audio component originating from a second position different from the first position; and

an adaptive filter to which the first signal is input and that outputs a passing signal based on the first signal, and

the processor further performs:

making a determination whether the first audio signal includes more of the first audio component or more of the second audio component based on a second signal and a third signal; and

controlling a filter coefficient of the adaptive filter based on a result of the determination, wherein

the adaptive filter has a first filter coefficient and a second filter coefficient different from the first filter coefficient,

when the processor determines that the first audio signal includes more of the first audio component than the second audio component, the adaptive filter outputs the passing signal based on the first signal and the first filter coefficient, and

when the processor determines that the first audio signal includes more of the second audio component than the first audio component, the adaptive filter outputs the passing signal based on the first signal and the second filter coefficient.

9. An audio processing method executed in an audio processing device, comprising:

receiving a first signal based on a first audio signal including a first audio component originating from a first position and a second audio component originating from a second position different from the first position;

providing the first signal to an adaptive filter having a first filter coefficient and a second filter coefficient different from the first filter coefficient;

outputting, by the adaptive filter, a passing signal based on the first signal;

determining whether the first audio signal includes more of which of the first audio component or more of the second audio component based on a second signal and a third signal; and

controlling a filter coefficient of the adaptive filter based on a result of the determination, wherein

in response to determining that the first audio signal includes more of the first audio component than the second audio component, controlling the filter coefficient includes controlling the adaptive filter to output the passing signal based on the first signal and the first filter coefficient, and

in response to determining that the first audio signal includes more of the second audio component than the first audio component, controlling the filter coefficient includes controlling the adaptive filter to output the passing signal based on the first signal and the second filter coefficient.