Patent ID: 6252968
Filing Date: 2001-06-26
Classification: H04R,H04S

Abstract:
A method of rapidly enhancing audio quality of an input audio signal in a portable computing system having limited resources and having a reproduction medium with unknown characteristics, said method comprising:a. generating a predetermined finite set of M single frequency tones;b. passing said set of tones through said reproduction medium to generate a subsequent output signal;c. passing said subsequent output signal through a set of sub-band filters, each of the sub-band filters passing at least a frequency corresponding to one of the M tones;d. estimating the unknown characteristics of said reproduction medium by examining outputs of each of said sub-band filters after passing said subsequent output signal through said medium to produce gain estimates;e. dynamically constructing a set of sub-band inverse filters to compensate for the estimated characteristics of the reproduction medium; andf. before passing an input audio signal through said reproduction medium, passing said audio signal through said inverse filters, thereby improving the audio quality after the audio signal passes through said reproduction medium.