Leakage compensation method and system for headphone

1. A leakage compensation method for a headphone, comprising:

filtering an audio signal to be played by a speaker of the headphone to generate an audio reference signal comprising a music reference signal;

obtaining an audio feedback signal based on a microphone signal acquired by a microphone of the headphone responsive to the audio signal being played by the speaker;

determining one or more compensation parameters of a compensation filter which compensates for a leakage condition of the headphone based on the music reference signal and the audio feedback signal;

configuring the compensation filter using the one or more compensation parameters; and

processing a music signal using the compensation filter to generate a leakage-compensated music signal to be played by the speaker,

wherein filtering the audio signal to generate the audio reference signal comprises:

determining one or more reference parameters of a reference-path filter;

configuring the reference-path filter using the one or more reference parameters; and

filtering the audio signal using the reference-path filter to generate the music reference signal,

wherein the leakage compensation method further comprises:

downsampling the audio signal using a first downsampling filter; and

downsampling the audio feedback signal using a second downsampling filter, and

wherein processing the music signal using the compensation filter to generate the leakage-compensated music signal to be played by the speaker comprises:

downsampling the music signal using a third downsampling filter to generate a downsampled music signal;

filtering the downsampled music signal using the compensation filter to generate an intermediate music signal;

upsampling the intermediate music signal using an upsampling filter to generate an upsampled intermediate music signal; and

adding the upsampled intermediate music signal to the music signal to generate the leakage-compensated music signal.

2. The leakage compensation method of claim 1 , wherein the audio reference signal further comprises a pilot tone signal.

3. The leakage compensation method of claim 1 , wherein:

if a strength of the music reference signal is equal to or greater than a first signal threshold, the audio reference signal is configured to comprise the music reference signal; or

if the strength of the music reference signal is smaller than the first signal threshold, the audio reference signal is configured to comprise the music reference signal and a pilot tone signal.

4. The leakage compensation method of claim 1 , wherein determining the one or more compensation parameters of the compensation filter comprises:

determining filter coefficients of the compensation filter at a time point of n+1 as follows:

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wherein h (n)=[h 0 (n), h 1 (n), h 2 (n), . . . , h M-1 (n)] T , f(n+1) denotes the filter coefficients of the compensation filter at the time point of n+1, n denotes an integer with n≥0, M denotes a length of the compensation filter, u denotes a step size of the compensation filter, y(n)=[y(n), y(n−1), . . . , y(n−M+1)] T denotes the audio feedback signal at a time point of n, e(n)=x(n)−h T (n)y(n) denotes a residual signal at the time point of n, and x(n) denotes the music reference signal at the time point of n.

5. The leakage compensation method of claim 2 , wherein responsive to the audio reference signal comprising the pilot tone signal, obtaining the audio feedback signal comprises:

generating the microphone signal by the microphone of the headphone responsive to the audio signal being played by the speaker; and

filtering the microphone signal using a passband filter to generate the audio feedback signal.

6. The leakage compensation method of claim 1 , wherein determining the one or more compensation parameters of the compensation filter comprises:

determining a current frequency response of an acoustic path from the speaker to the microphone based on the audio signal and the audio feedback signal; and

determining the one or more compensation parameters of the compensation filter based on the current frequency response of the acoustic path and a predetermined matching relationship between a group of reference frequency responses of the acoustic path and a group of reference parameter sets of the compensation filter.

7. The leakage compensation method of claim 6 , wherein determining the one or more compensation parameters of the compensation filter based on the current frequency response of the acoustic path and the predetermined matching relationship comprises:

determining, from the group of reference frequency responses, one or more reference frequency responses that match the current frequency response;

determining, from the group of reference parameter sets, one or more reference parameter sets corresponding to the one or more reference frequency responses; and

determining the one or more compensation parameters based on the one or more reference parameter sets.

8. The leakage compensation method of claim 7 , wherein:

the audio reference signal comprises the music reference signal and a pilot tone signal; and

determining, from the group of reference frequency responses, one or more reference frequency responses that match the current frequency response comprises:

determining a first reference frequency response that matches the current frequency response in a predetermined music frequency band; and

determining a second reference frequency response that matches the current frequency response in a predetermined pilot tone frequency band.

9. The leakage compensation method of claim 8 , wherein determining, from the group of reference parameter sets, the one or more reference parameter sets corresponding to the one or more reference frequency responses comprises:

determining, from the group of reference parameter sets, a first reference parameter set corresponding to the first reference frequency response; and

determining, from the group of reference parameter sets, a second reference parameter set corresponding to the second reference frequency response.

10. The leakage compensation method of claim 9 , wherein determining the one or more compensation parameters based on the one or more reference parameter sets further comprises:

determining a deviation between the first and second reference frequency responses.

11. The leakage compensation method of claim 10 , wherein determining the one or more compensation parameters based on the one or more reference parameter sets further comprises:

responsive to the deviation being smaller than a deviation threshold, determining the one or more compensation parameters based on a weighted combination of the first and second reference parameter sets.

12. The leakage compensation method of claim 10 , wherein determining the one or more compensation parameters based on the one or more reference parameter sets further comprises:

responsive to the deviation being equal to or greater than a deviation threshold and a strength of the music reference signal is smaller than a first signal threshold and greater than a second signal threshold, determining the one or more compensation parameters based on the first reference parameter set.

13. A headphone comprising:

a speaker configured to play an audio signal;

a microphone configured to acquire a microphone signal responsive to the audio signal being played by the speaker;

a processor configured to:

filter the audio signal to be played by the speaker to generate an audio reference signal comprising a music reference signal;

obtain an audio feedback signal based on the microphone signal;

determine one or more compensation parameters of a compensation filter which compensates for a leakage condition of the headphone based on the music reference signal and the audio feedback signal; and

configure the compensation filter using the one or more compensation parameters; and

a compensation filter configured to process a music signal to generate a leakage-compensated music signal to be played by the speaker,

wherein the headphone further comprises a reference-path filter, a first downsampling filter, a second downsampling filter, a third downsampling filter, and an upsampling filter,

wherein to filter the audio signal to generate the audio reference signal, the processor is further configured to:

determine one or more reference parameters of the reference-path filter;

configure the reference-path filter using the one or more reference parameters; and

filter the audio signal using the reference-path filter to generate the music reference signal,

wherein the processor is further configured to:

downsample the audio signal using the first downsampling filter; and

downsample the audio feedback signal using the second downsampling filter, and

wherein the processor is further configured to:

downsample the music signal using the third downsampling filter to generate a downsampled music signal;

filter the downsampled music signal using the compensation filter to generate an intermediate music signal;

upsample the intermediate music signal using the upsampling filter to generate an upsampled intermediate music signal; and

add the upsampled intermediate music signal to the music signal to generate the leakage-compensated music signal.

14. The headphone of claim 13 , wherein the audio reference signal further comprises a pilot tone signal.

15. The headphone of claim 13 , wherein:

if a strength of the music reference signal is equal to or greater than a first signal threshold, the audio reference signal is configured to comprise the music reference signal; or

if the strength of the music reference signal is smaller than the first signal threshold, the audio reference signal is configured to comprise the music reference signal and a pilot tone signal.

16. The headphone of claim 13 , wherein to determine the one or more compensation parameters of the compensation filter, the processor is further configured to:

determine a current frequency response of an acoustic path from the speaker to the microphone based on the audio signal and the audio feedback signal; and

determine the one or more compensation parameters of the compensation filter based on the current frequency response of the acoustic path and a predetermined matching relationship between a group of reference frequency responses of the acoustic path and a group of reference parameter sets of the compensation filter.

17. A leakage compensation system for a headphone, comprising:

a memory storing code; and

a processor coupled to the memory, wherein when the code is executed, the processor is configured to:

filter an audio signal to be played by a speaker of the headphone to generate an audio reference signal comprising a music reference signal;

obtain an audio feedback signal based on a microphone signal acquired by a microphone of the headphone responsive to the audio signal being played by the speaker;

determine one or more compensation parameters of a compensation filter which compensates for a leakage condition of the headphone based on the music reference signal and the audio feedback signal;

configure the compensation filter using the one or more compensation parameters; and

process a music signal using the compensation filter to generate a leakage-compensated music signal to be played by the speaker,

wherein to filter the audio signal to generate the audio reference signal, the processor is further configured to:

determine one or more reference parameters of a reference-path filter;

configure the reference-path filter using the one or more reference parameters; and

filter the audio signal using the reference-path filter to generate the music reference signal,

wherein the processor is further configured to:

downsample the audio signal using a first downsampling filter; and

downsample the audio feedback signal using a second downsampling filter, and

wherein to process the music signal using the compensation filter to generate the leakage-compensated music signal to be played by the speaker, the processor is further configured to:

downsample the music signal using a third downsampling filter to generate a downsampled music signal;

filter the downsampled music signal using the compensation filter to generate an intermediate music signal;

upsample the intermediate music signal using an upsampling filter to generate an upsampled intermediate music signal; and

add the upsampled intermediate music signal to the music signal to generate the leakage-compensated music signal.