Patent ID: 6990205

Claim:
A method of reducing the amount of computations required to create a sound signal representing one or more sounds originating at a plurality of discrete positions in space, where the signal is to be perceived as simulating one or more sounds at one or more selected positions in space with respect to a listener, comprising the steps of: determining a spatial characteristic function for a position in space at which sound originating at a plurality of positions in space is to be received, wherein said characteristic function represents a head-related impulse response; applying said characteristic function as a filter to said signal representing sound to produce a filtered signal; and converting said filtered signal to a sound wave and producing said sound wave for a listener; wherein said spatial characteristic function is determined for a selected number of N samples and a selected number of M eigen values and wherein said filter with a function for an azimuth position θ and an elevation position of sound originating in a spherical coordinate system about said position of sound measurement as said origin has a form y ⁡ ( n ) = ∑ m = 1 M ⁢ ⁢ [ ∑ k = 1 K ⁢ ⁢ w m ⁡ ( θ k , φ k ) ⁢ s k ⁡ ( n ) ] ⁢ q m ⁡ ( n ) 9 ⁢ ( c ) where s represents a sound source, K represents a number of independent sound sources, w m (θ, ) are weighting factors, and q m (n) is a vector representing an orthonormal basis for a head-related impluse function.