Patent ID: 11862140
Assignee: AMS AG
Field: Other consumer goods (Other fields)
Classification: CPC G  H | IPC G  H

Claim 18:
19. A signal processing method for an ear mountable playback device comprising a speaker, a feedforward microphone that predominantly senses ambient sound and an error microphone that senses sound being output from the speaker, the method comprising
recording a noise signal from the feedforward microphone and using the noise signal as a detection signal;
filtering the detection signal with a feedforward filter;
controlling a playback of the filtered detection signal via the speaker;
recording an error signal from the error microphone;
performing noise cancellation based on at least one of the noise signal and the error signal; and
determining whether the playback device is in a first state, where the playback device is worn by a user, or in a second state, where the playback device is not worn by a user, based on processing of the error signal, and
wherein the sound control processor is configured to determine the first state and/or the second state based on an evaluation of a performance of the noise cancellation as a function of the error signal and the detection signal.