Shadow Sound System Embodied with Directional Ultrasonic Speaker: User Following Sound System Enabled with Vision Tracking Technique

The Shadow Sound system is an innovative sound platform started from the concept of making sound seamlessly tracking a designated user by harnessing the directivity of a mobilized ultrasonic speaker. The motivation of this system development is to enable a totally personalized ubiquitous sound delivery within a typical 3-dimensional space without using headphone or other external sound blocking device. In order to achieve this goal, we combined an ultrasonic speaker system installed on the motorized mount that can freely change the speaker´s azimuth and altitude plus the computer vision based user image tracking algorithm operable with combined image difference and color tracking. The resulting system is proven to be able to track the registered user for providing user selected sound contents without being interfered by other people and ambient noise coexisting in the same physical environment. Such innovative sound solution would open up a new horizon of personalized sound consumption in a ubiquitous computing dominating environment.