Steering of camera by stepper motor towards active speaker using microphone array

This paper describes camera steering for bringing in focus the active speaker using microphone array. Automatic camera steering has many important applications such as video conferencing, surveillances and monitoring. The system proposed here uses a linear microphone array to capture speech signal from the speakers and a stepper motor based camera steering unit (CSU). The captured speech signals are analyzed to estimate direction of arrival (DOAs) of the speakers using multiple signal classification (MUSIC) algorithm. The estimated DOA is further inputted to the CSU which contains a stepper motor for steering the camera to the estimated direction. The experimental results suggest that high resolution MUSIC algorithm can be effective in steering camera in the noisy environment too if the number of sensors in array is increased. However, it also ups the computational cost.

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