Patent ID: 8442250

Claim:
A hearing aid, comprising: a signal path for receiving at least one wideband audio input signal; autocorrelation index (ACI) estimating means, comprising: down-sampling means for producing a sampling-rate reduced signal of said audio input signal; sign extraction means for extracting a sign signal of said sampling-rate reduced signal; memory and delay means for producing and storing delayed versions of said sign signal; comparison means for producing a subset of the delayed versions of said sign signal and comparing said subset with a version of the audio input signal; averaging means for averaging outputs of the comparison means to extract delay specific estimates of the signals self-resemblance of the delayed versions of said sign signal and the audio input signal; and autocorrelation index estimating means for obtaining an estimated autocorrelation index by determining summarized features from the delay specific estimates of the signals self-resemblance of said signals, wherein said summarized features define summarized informative ACI features.