SPEECH PROCESSING FOR PLURALITY OF USERS
A mobile communication device configured to communicate over a wireless network has an audio processing circuit that is adaptable based on a pattern of the speaker's voice to provide improved audio quality and intelligibility. The audio processing circuit is configured to receive a voice signal from an individual speaker, to determine a pattern associated with the speaker's voice, and to adjust a filter based on the determined pattern.
1 . A method for processing an audio speech signal, comprising:
determining at least one characteristic of an audio speech signal;
associating the audio speech signal with a speaker in response to determination of the at least one characteristic; and
configuring a filter based on the associated speaker; and
applying the filter to the audio speech signal.
2 . The method of claim 1 , wherein the act of determining at least one characteristic of an audio speech signal comprises determining a frequency spectrum of the audio speech signal.
3 . The method of claim 1 , wherein the act of associating the audio speech signal with a speaker comprises comparing at least a portion of the frequency spectrum of the audio speech signal to a speaker profile, the resulting comparison indicative of a profiled speaker.
4 . The method of claim 1 , wherein the act of determining at least one characteristic of an audio speech signal comprises determining a frequency cepstrum of the audio speech signal.
5 . The method of claim 4 , wherein the act of determining the frequency cepstrum comprises:
obtaining a frequency spectrum of the audio speech signal;
determining a logarithmic amplitude of the frequency spectrum; and
performing a frequency transformation of the logarithmic amplitude frequency spectrum, yielding a frequency cepstrum of the audio speech signal.
6 . The method of claim 4 , wherein the act of associating the audio speech signal with a speaker comprises comparing at least a portion of the frequency cepstrum of the audio speech signal to a speaker profile, the resulting comparison indicative of a profiled speaker.
7 . The method of claim 1 , wherein the act of selecting a filter based on the associated speaker comprises adjusting an adjustable filter.
8 . The method of claim 1 , wherein the act of selecting a filter based on the associated speaker comprises providing coefficients to a digital filter.
9 . The method of claim 1 , wherein at least one of the acts is performed in a digital signal processor.
10 . A mobile communications device for processing an audio speech signal, comprising:
signal analyzer receiving at least a sample of an audio speech signal and determining at least one characteristic feature thereof;
signal characterizing module receiving from the signal analyzer the at least one characteristic feature of the at least one sample of the audio speech signal, and associating therewith a speaker; and
a filter selector selecting a filter based on the associated speaker, wherein the selected filter provides a listener with an improved audio experience.
11 . The mobile communications device of claim 10 , wherein at least one of the signal analyzer, the signal characterizing module, and the filter selector is implemented in a digital signal processor.
12 . The mobile communications device of claim 10 , further comprising a host processor implementing instructions related to at least one of the signal analyzer, the signal characterizing module, and the filter selector.
13 . The mobile communications device of claim 10 , wherein the signal analyzer is configured to determine a frequency spectrum of the audio speech signal.
14 . The mobile communications device of claim 10 , wherein the signal analyzer is configured to determine a frequency cepstrum of the audio speech signal.
15 . The mobile communications device of claim 10 , further comprising memory for storing at least one of sample of an audio speech signal, characteristic feature of the at least one sample, and filter selections.
16 . The mobile communications device of claim 10 , further comprising an adjustable filter in communication with the filter selector, the adjustable filter tailoring its filter profile responsive to the filter selection.
17 . The mobile communications device of claim 16 , wherein the adjustable filter comprises a digital filter.
18 . The mobile communications device of claim 17 , wherein the digital filter comprises a finite impulse response filter.
19 . The mobile communications device of claim 10 , wherein the mobile communications device is a cellular radiotelephone.
20 . An apparatus for processing an audio speech signal, comprising:
means for determining at least one characteristic of an audio speech signal;
means for associating the audio speech signal with a speaker in response to determination of the at least one characteristic; and
means for selecting a filter based on the associated speaker, wherein the selected filter, when applied to the audio speech signal, provides a listener with an improved audio experience.