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Mathias, <div>Are you familiar with Interferometry?<br>Used in localization of electromagnetic signals, among multitude of other applications.</div><div><br></div><div>http://en.wikipedia.org/wiki/Interferometry</div><div><br>Zax<br><div><div id="ecxSkyDrivePlaceholder"></div>From: m.schaefer@uni-weimar.de<br>Date: Sun, 9 Dec 2012 23:15:31 +0100<br>To: pd-list@iem.at<br>Subject: [PD] Sound localization<br><br><pre>Hello people,<br> <br>I'm trying to build a patch with which I can locate a sound source with microphones (right now using the Playstation Move Camera with the build in 4 channel microphone array).<br>So far I found out that there are 3 ways to locate sound sources (correct me if I'm wrong):<br> <br>1. Energybased method: <br>Basically you check the "loudness" of the sound with at least two different microphones in a microphone array. By doing this the microphone which is further away to the sound source gives a signal which is more quiet, so you can roughly determine the location. Problems: <br>- You need a completely quiet room for best results <br>- Walls reject the sound wave, which gives irregularities<br> <br>2. Beamforming:<br>You get the direction of the sound by delaying the array signals and summing them up, thus creating a direction response of the array. How the exact process works and why is a mystery to me so far.<br> <br>3. Time Delay Estimation-based Localization:<br>You calculate the delayed time of the amplitudes peaks and get the result in milliseconds. By this you can determine which microphone is closer to the sound source<br> <br>Attached is a small patch where I tried out the energy based method with the "bonk" utility, the results I get with that are quite sloppy<br></pre><br>Anybody there who already tried something with locating sound in pd? Or got any good advice?
Thanks in advance,
Matthias<br>_______________________________________________
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