Processing Audio Data using Fourier Transforms in Java

Question

Hi,

I'm trying to process audio data. I'm working with Java. I've extracted the audio data to an array. Now I should pass N data samples to a function that calculates the Discrete Fourier Transform (or Fast Fourier Transform, which is more efficient). I've read documentation but I'm getting more and more confused. What I'm trying to calculate is the magnitude spectrum (|X(k)|). Can anyone help me? Thanks

Answer 1

Richard G. Baldwin has a number of very good articles on Fast Fourier Transform algorithms in Java on the Developer.com website. In particular, the following articles should prove to be useful:

Fun with Java, Understanding the Fast Fourier Transform (FFT) Algorithm http://www.developer.com/java/other/article.php/3457251

Spectrum Analysis using Java, Sampling Frequency, Folding Frequency, and the FFT Algorithm http://www.developer.com/java/other/article.php/3380031

Answer 2

if you only want Magnitude Spectrum of audio, go for jAudio API. http://www.music.mcgill.ca/~mcennis/doc/index.html it provides class for calculating MS.