US Patent 10024712 Acoustic presence detector

One or more embodiments set forth an audio presence detection system, with a memory that includes an acoustic presence detection application, and a processor that executes the acoustic presence detection application. The audio presence detection system receives a first input signal associated with a first speaker, and receives a second input signal associated with a first microphone. The audio presence detection system generates, via an adaptive filter, a first estimation signal based on at least the first input signal and an impulse response associated with a room related to the first speaker and the first microphone. The audio presence detection system computes a first error signal based on the second input signal and the first estimation signal. The audio presence detection system determines that an object is present within a space based on a magnitude associated with the first error signal relative to a first threshold level.