| CPC G10L 21/0232 (2013.01) [G10L 2021/02082 (2013.01)] | 21 Claims |
|
1. An audio signal processing method implemented by an audio system which comprises at least an internal sensor, an external sensor and a speaker unit, wherein the internal sensor is arranged to measure voice acoustic signals emitted by a user of the audio system which reach the internal sensor by propagating internally to a head of the user and the external sensor is arranged to measure voice acoustic signals emitted by the user which reach the external sensor by propagating externally to the user's head, wherein the audio signal processing method comprises:
producing an internal audio signal and an external audio signal by measuring simultaneously acoustic signals reaching the internal sensor and acoustic signals reaching the external sensor, respectively, wherein the audio system is an earbud or headphone device,
converting the internal audio signal to frequency domain, thereby producing an internal audio spectrum,
converting the external audio signal to frequency domain, thereby producing an external audio spectrum,
estimating, based on the internal audio spectrum, an echo audio spectrum of an echo audio signal caused by the speaker unit in the external audio signal, wherein the echo audio spectrum is estimated for frequencies above a minimum frequency, wherein the minimum frequency is greater than higher or equal to 600 hertz, and wherein the internal audio spectrum, the external audio spectrum and the echo audio spectrum are complex spectra,
correcting the external audio spectrum for frequencies above the minimum frequency, based on the echo audio spectrum, including subtracting the echo audio spectrum from the external audio spectrum for frequencies above the minimum frequency, and
combining the corrected external audio spectrum with the internal audio spectrum to produce an output audio spectrum.
|