The Research And DSP Implementation On Virtual Acoustic Space And Virtual Surrounding Technology

Virtual Auditory Space adds the 3D virtual sound simultaneously with the vision in virtual environment, in which people can perceive the sound as in reality. Human auditory perceive not only includes the level, tone and timbre of sound, but also the sound location, which is called the spatial hearing ability. Long-term researches have been conducted in the fields of hearing physiology, hearing psychology and acoustics, and make much progress in spatial hearing. With the rapid development of computer science and information technology, investigations on spatial hearing have received more and more attention and the application has become wider. Head-related impulse response (HRIR) and head-related transfer function (HRTF) play a key role on the research of spatial hearing. Based on signal and information processing technology, this thesis establishes Virtual Auditory Space and Virtual Surrounding system.The content of this thesis mainly includes the following parts:1. Introduce the measuring methods, amplitude and phase characteristic of HRTFs in CIPIC (Center for Image Processing and Integrated Computing ) HRTF.2. Analyze the principle of Virtual Auditory Space and Virtual Surrounding system, and point out the limitation and improvement method. Introduce the fast convolution algorithm and multiple buffer technology in detail for accomplishing the system in real time. Compare three methods to realize the Doppler Effect.3. Propose the algorithm to implement the two systems on DSP5416, including memory distribution, program fixing, mix program, pipeline and so on. Analyze the compression of HRIR by PCA and Real-Time Data Exchange (RTDX) technology.4. Propose the improvement of the two systems in personality, reverberation and equilibrium.