17 07 2013
The idea of writing a Fast Fourier Transformation came to me when we had to chose a project for my embedded system class.
At that time, we were given the Stellaris LM3S6965 Ethernet Evaluation Kit to work with.
I’d just learned about the Fourier transformations and I really wanted to try and code a Fast Fourier Transformation. So why not try this on the Stellaris board ?
This board has a 128×64 OLED display which is excellent for me to display the amplitudes of the Fourier transformation.
15 07 2013
I was given the idea to make an equalizer, or to at least try making one.
The way you make an equalizer is by taking some audio samples, use the FFT transformation on those samples then modify the amplitude of the FFT output at the desired frequencies and use those modified amplitudes as an input for an inverse FFT.
The output of the inverse FFT will give you a new set of samples that you can use and send to a DAC or other digital to analog converter.
29 06 2013
Part 2 of How to program a Fast Fourier Transformation.
In this part I’m going to show you and explain the code I have written in the library.
22 06 2013
First tutorial !
In this post I’m going to try and teach you how to program a Fast Fourier Transform.
Before we start with coding all sorts of fun stuff, we need to see a bit of the mathematics used in the FFT.