Design Of 3D Sound Sensing Based On Head Position Detection

In recent years,the rapid development of virtual reality(VR)and augmented reality(AR)technologies have placed urgent demands on high-quality 3D audio and video technology,among which 3D sound technology is relatively backward.The three-dimensional virtual sound perception system can make the user get better immersion and interaction by three-dimensional positioning and real-time tracking of the sound source.The research on it has important theoretical significance and practical value.In this thesis,3D sound perception system based on head position detection is designed,which uses head-related transfer function(HRTF)to generate the virtual sound so as to keep the perceived sound source localization unchanged when the head moves.The core modules of the designed system include head position perception,HRTF interpolation and 3D sound processing.The realization of head position perception utilizes the gesture sensor based on chip of MPU9250.The perceived movements of head include rotation and pitch.This thesis uses the PKU&IOA HRTF database to achieve 3600 sound sensing.This work focuses on the research and improvement of HRTF interpolation algorithm.Based on the analyses and comparison of bilinear interpolation method and triangular interpolation method,and according to the characteristics of human auditory system,a modified triangular interpolation algorithm is proposed,which introduces different compensating coefficients for the interpolation of right and left ear's HRTF according to the position information,and the interpolation performance of HRTF is improved.The thesis finally realized a 3D sound sensing prototype system based on headphones.The HRTF interpolation algorithm and real-time processing of 3D sound sensing is implemented on the embedded processor STM32F767.The MPU9250 is fixed on the earphone and communication with STM32F767 through I2C bus.The chip of WM8978 is used to realize the A/D and D/A converting for the input and output of audio.Finally,this thesis conducted an informally subjective hearing test on the designed system.The test results show that the 3D sound sensing system can provide good perception performance for the azimuth changing,while the elevation sensing accuracy is slightly weak,also the quality of the reconstructed audio signal is good,which achieved the research purpose of this thesis.