Hi all.
I've been busy with DSP in the past few days and i'd like to ask you guys some questions about it.
First of all, let me explain what i did. I built a java program which records sound and stores the samples in an array. All simple. What i want to do now, is analyze this signal and see which frequencies are present in it.
As i understand, i need to use FFT to transform this signal from time domain to a frequency domain. What i do is i get the samples, pass them to this program, which in turn, gives out imaginary and real values of my signal.
My question is, what are these values supposed to represent? Are they the power of the signal at certain frequencies? More over, i'm confused about the polarities. I have positive and negative values in my samples, i pass them to this program and it returns positive and negative, real and imaginary values. Am i supposed to take their absolute values at some point?
Thanks a lot.