A head-related transfer function model for fast synthesizing multiple virtual sound sources

A head-related transfer function(HRTF) model for fast and real-time synthesizing multiple virtual sound sources is proposed.A head-related impulse response(HRIR,time-domain version of HRTF) is first decomposed by a two-level wavelet packet and then represented by a model composed of subband filters and reconstruction filters.The coefficients of the subband filters are the zero interpolation of the wavelet coefficients of the HRIR.The coefficients of the reconstruction filters can be calculated from the wavelet function.The model is simplified by applying a threshold method to reduce the wavelet coefficients.The calculated results indicate that for a model with 30 wavelet coefficients,the error of reconstructed HRIR is about 1%.And the result of a psychoacoustic test shows that a model with 35 wavelet coefficients is perceptually indistinguishable from the original HRIR.When multiple virtual sound sources are synthesized simultaneously,the computational cost of the proposed model is much less than the traditional HRTF filters.