Patent ID: 6970567
Filing Date: 2005-11-29
Classification: H04S

Abstract:
1. A method of deriving one of a plurality of output audio signals from two input audio signals S 1 (α) and S 2 (α), the output audio signal associated with a principal direction β2, the input audio signals encoded with an audio source signal having a direction α, comprising generating two antidominant audio signals of the form: and wherein in one antidominant signal the angle β 1 is the angle of one of the two principal directions adjacent to the principal direction β 2 of the output audio signal and in the other antidominant signal the angle β 3 is the angle of the other of the two principal directions adjacent to the principal direction β 2 of the output audio signal, and wherein the coefficients AS 1 β 1 and AS 2 β 1 are selected so that the one antidominant signal is substantially zero when α is β 1 and the coefficients AS 1 β 3 and AS 2 β 3 are selected so that the other antidominant signal is substantially zero when α is β 3 , applying amplitude control to the two antidominant signals to deliver a pair of signals having substantially equal magnitudes, and additively or subtractively combining the amplitude controlled antidominant audio signals to provide the output audio signal.