Patent ID: 8126173

Claim:
An apparatus, comprising: a band-splitting filter bank configured to receive, split, and filter a left input signal and a fight input signal into a plurality of frequency sub-bands, each of the frequency sub-bands comprising a left sub-band signal and a fight sub-band signal; a plurality of synthesis structures, each synthesis structure comprising a gain control unit and configured to receive the left and right sub-band signals associated with one of the frequency sub-bands and to process the received left and right sub-band signals into a plurality of sub-band channel signals, wherein the gain control unit is configured to calculate a plurality of frequency sub-band specific gain values for each of the sub-band channel signals using predetermined windows, each frequency sub-band specific gain value for one of the sub-band channel signals adjusted between a maximum gain and an ideal gain based upon a presence of a dominant signal in the sub-band channel signals, wherein the plurality of sub-band channel signals comprises: a plurality of left sub-band channel signals, a plurality of right sub-band channel signals, a plurality of center sub-band channel signals, a plurality of left surround sub-band channel signals, and a plurality of right surround sub-band channel signals; and a mixer configured to sum a corresponding plurality of sub-band channel signals received from an output of the synthesis structures into a respective left channel, right channel, center channel, left surround channel, and right surround channel.