SYNTHESIZING 3D SOUND SYNTHESIZING 3D SOUND AND AND SOUND - PowerPoint PPT Presentation

SYNTHESIZING 3D SOUND SYNTHESIZING 3D SOUND AND AND SOUND LOCALIZATION SOUND LOCALIZATION Eric Fuller Eric Fuller Banky Omodunbi Banky Omodunbi Sheng_Lung Lee _Lung Lee Sheng

Head Related Transfer Functions Head Related Transfer Functions  An HRTF is an impulse response from the source of the An HRTF is an impulse response from the source of the  sound to the human ear drum. sound to the human ear drum.  It is caused by the effect of a human It is caused by the effect of a human’ ’s head and ears. Each s head and ears. Each  person’ ’s perception of a given sound signal varies with s perception of a given sound signal varies with person his/her pinna pinna structure. structure. his/her

Generating 3D Sound Generating 3D Sound  3D sound is generated by convolution of a 3D sound is generated by convolution of a  given HRTF with the input sound signal. given HRTF with the input sound signal.  Based on a selected azimuth and elevation Based on a selected azimuth and elevation  value a given HRTF is used. value a given HRTF is used.

Sound Localization Sound Localization  There is a slight delay between when a sound There is a slight delay between when a sound  arrives at the left and right ears. arrives at the left and right ears.  Cross-Correlation of the signals at each ear can Cross-Correlation of the signals at each ear can  be used to determine the delay between them. be used to determine the delay between them.  The delay can be used to find azimuth of the The delay can be used to find azimuth of the  sound source with the equation: sound source with the equation:

The Onset Algorithm The Onset Algorithm  Echoes can interfere with a simple cross- Echoes can interfere with a simple cross-  correlation method. correlation method.  The sound can be treated with the Onset The sound can be treated with the Onset  Algorithm, making the cross-correlation Algorithm, making the cross-correlation immune to echoes. immune to echoes.  The Onset Algorithm places more emphasis The Onset Algorithm places more emphasis  on the beginning of the sound signal. on the beginning of the sound signal.

Onset Algorithm Onset Algorithm

Correlation Examples Correlation Examples

Estimation Results Estimation Results