![]() ![]() Just slide the samples of each mic, subtract one from the other until all points are 0. In an ideal world, that would be trivial. In order to locate the origin of that sound, we first need to calculate the TDOAs (Time Difference of Arrival) between each signal. ![]() This is something to consider when recording samples, the bigger the distance between mics the more memory you need in your hardware platform. General formula for the minimum samples is Dm/SS*SR, where Dm is the greatest distance between mics in millimetres, SS is the speed of sound in m/s (which is the same as mm/ms) and SR is the sample rate in kHz (which is the same for samples/ms). So my choice was around 4 times that, or 2048 bytes. Given the Teensy sampling at around 454kHz, the greatest diference between mics srqt(25*25+25*25)=35.355cm, minimum sound speed lets say 320 m/s, the maximum distance in samples from the start of the sound in one mic to the most distant one is given by 353.55/320*454 ~= 500 samples. The buffer is 2048 bytes sampled at ~454kHz, the grey line shows when the threshold was crossed.
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