Patent ID: 7885414
Filing Date: 2011-02-08
Classification: H04S

Abstract:
1. A method of synthesizing stereo sound from a monaural sound signal comprising the steps of: band stop filtering the monaural sound signal having a predetermined stop band; producing first and second decorrelated band stop filtered signals by filtering an input with respective first and second complementary comb filters, wherein frequency peaks of said first comb filter matches frequency notches of said second comb filter and frequency notches of said first comb filter matches frequency peaks of said second comb filter, said first comb filter having a transfer function C said second comb filter having a transfer function C 1 (z) calculated by where: z is an input variable; D is a delay factor; and α is a scaling factor; band pass filtering the monaural sound signal having a predetermined pass band, said predetermined band pass being equal to said predetermined stop band; summing said band pass filtered monaural sound signal and said first decorrelated band stop filtered signal to produce a first stereo output signal; and summing said band pass filtered monaural sound signal and said second decorrelated band stop filtered signal to produce a second stereo output signal.