Comparison between Spherical Headmodels and HRTFs in Upmixing for Headphone Based Virtual Surround and Stereo Expansion - I

摘要

In this paper, a first of multiple-parts, we compare the performance of headmodels with head-related transfer functions (HRTFs), which have previously been published, using different upmixing techniques for headphone virtual surround. We consider a spherical head whereas for the HRTFs we incorporate the CIPIC and Nagoya HRTF sets in the up-mixing. The up-mixing technique includes using the Moorer reverberator, a modified Moorer reverberator and modeling the direct sound, the first several discrete reflections (with adjustable delay and amplitude) and the diffuse field reflections with a tunable frequency dependent decorrelator and the reverberation with the Moorer model. Furthermore, since the measured HRTFs can introduce audible coloration we investigate if there is a trade-off between localization and timbre by incorporating complex-domain smoothing of the HRTF time responses. To evaluate the localization and timbre performance between the models we will use movie and music content (viz., stereo, ITU down-mix, and a commercial down-mix method) as well as Gaussian tone noise bursts of critical bandwidth in upcoming papers.