Determining ITDs Using Two Microphones on a Flat Panel During Onset Intervals With a Biologically Inspired Spike-Based Technique

Using a mockup of a flat panel display, with two omnidirectional microphones we have used intermicrophone time difference (ITD) to determine the azimuthal direction of a sound source (speaker). The speaker is in a noise field in an office-type environment. Bandpass filtering followed by a biologically inspired low latency onset detector (which can cope with a considerable dynamic range) determines the intervals and spectral locations in which an onset is occurring. Direction determination during these onset intervals enables discovery of the onsetting sound´s azimuthal angle even in the presence of competing sounds. We compare the results from cross-correlation and novel spike based techniques for determining azimuthal angle during these onset intervals. We note that the system is suitable for real-time implementation.