Synchronization of signals using leading edge detection

Hello everyone, I'm trying to perform an audio signal analysis over two signals acquired via different acquisition systems (so acquisitions are not synchronized). A short time before the usuful part of the signals, i send an impulsion.

I would like to use this impulsion to sync my two signals (required for phasis analysis).

Is there an easy way to do it ? (My signals are in wav format, and imported in matlab as vectors)

[Gautam Mohan]

Hi Benoit

If the impulse has a significantly higher magnitude than the rest of your audio signal, you can find the index where it occurs using max().

Assuming the impulse has a similar shape in both signals, you might consider using the xcorr() function to calculate the cross-correlation between the two signals. The cross-correlation of the two signals will peak at the alignment where the impulse lines up in both.

Here is the documentation for the xcorr() function; its examples describe synchronizing multiple signals:

http://www.mathworks.com/help/signal/ref/xcorr.html

Hope this helps!