A New HRTF Interpolation Approach for Nonlinear 3D Audio Systems

Binaural synthesis plays a vital role in 3D audio systems, relying on head-related transfer functions (HRTFs) to achieve realistic sound rendering. However, the reproduction system used in the HRTF measurement can introduce nonlinearities that impact the immersive experience. In light of this, the present study introduces a robust HRTF identification method designed to address these nonlinearities. Additionally, a novel HRTF interpolation technique is proposed, aiming at reducing the required number of measurement points while still ensuring faithful reproduction of the virtual auditory scene. Specifically, the interpolation is applied following a frequency warping process, which enhances the representation of lower frequencies within the HRTFs while simultaneously reducing the number of frequency bins. The resulting interpolated HRTFs are then unwrapped and utilized for binaural reproduction, contributing to an improved audio experience.