Great and very useful work!
The only drawbacks are that the function findpeaks already comes with MATLAB and you make heavy use of global variables (can lead to bad side effects when used in conjunction with other code).
Consider using a namespace or rename the function and generally check mlint results (this should also improve performance).
There is a typo there on my part; the number should be 1.06447.... Here's why: The simplest expression for a Gaussian peak is y=exp(-x^2). This has a full-width at half maximum of 2 * sqrt(ln(2)=1.66561 and the area under the curve is sqrt(pi)= 1.77245. So the width/height ratio is 1.06447.... The peak area is proportional to both peak height and width. Therefore the area is 1.06447 * peak height * peak width. Hint: You can use Wolfram Alpha (http://www.wolframalpha.com) to do all the algebra for stuff like that.
Sorry about this really basic question, but could you please explain to me the reasoning behind calculating the area of the peak using 1.0646 * peak height * peak width? I'm not sure where the 1.0646 value comes from.
Iman, you can use File > Import Data to import data files in various format, including three sound formats (.au, .snd, and .wav). These is also a Data Acquisition Toolbox that I would assume has additional data import capabilities.