It is difficult to completely explain the Fourier transform to you unless you already have some understanding of discrete signal analysis. However, all the mathematics you have seen on Wikipedia is to achieve one goal, and that in respect to sound that goal is to transform a discrete time signal into it’s frequency domain counterpart. The Fourier frequency domain is what we call a complex quantity, meaning it is written in Cartesian coordinates like vectors. From this complex number you can extract the phase and magnitude. The Magnitude spectrum is widely used to describe the power of the frequencies present in a signal. And in Speech Enhancement for Android, all the speech analysis is done by showing the magnitude spectrum. Anyway, I can’t really teach you the arithmetic methods of Fourier analysis, however, there are many many good books out there. But first you will need to brush up on your algebra skills.

If you are looking at programming the FFT in Android I can help. In fact I have an entirely separate blog with several posts with examples and free source code. Check out

http://www.digiphd.com/android-java-simple-fft-libgdx

Hope this helps.

My name is Makar, I am a student at Dublin City University studying computer applications. Currently I am trying to work on an app for the Android mobile phone which requires the use of FFT. Unfortunately my college does not teach signal processing and I was hoping maybe you could help.

To start, I have no idea where to begin in understanding FFT, I have of course googled it all but if I am honest, wikipedia scared me half to death trying to read it. I was hoping maybe you may have a way of explaining how this all works to a newbie.

The app I am developing I hope to record a sound and give real time information about the recorded sound. This is merely for studying purposes this project. I hope to make more advanced projects in the future knowing this skill so your help would be much appriciated. Also I have to say your Speech Enhancement app looks quite stunning if I am honest.

Hope to hear from ya soon mate, thanks for reading

Makar