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Ultrasonic echo canceler-based technique to detect participant presence at a video conference endpoint
Ultrasonic echo canceler-based technique to detect participant presence at a video conference endpoint
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机译:基于超声回声消除器的技术,可检测视频会议端点上的参与者是否在场
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摘要
A loudspeaker transmits an ultrasonic signal into a spatial region. A microphone transduces ultrasonic sound, including an echo of the transmitted ultrasonic signal, received from the spatial region into a received ultrasonic signal. A controller transforms the ultrasonic signal and the received ultrasonic signal into respective time-frequency domains that cover respective ultrasound frequency ranges. The controller computes an error signal, representative of an estimate of an echo-free received ultrasonic signal, based on the transformed ultrasonic signal and the transformed received ultrasonic signal. The controller computes power estimates of the error signal over time, and detects a change in people presence in the spatial region based on a change in the power estimates of the error signal over time.
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